Module:Citation/CS1: Difference between revisions

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    local z = {
    require('Module:No globals');
    error_categories = {}; -- for categorizing citations that contain errors
    error_ids = {};
    message_tail = {};
    maintenance_cats = {}; -- for categorizing citations that aren't erroneous per se, but could use a little work
    properties_cats = {}; -- for categorizing citations based on certain properties, language of source for instance
    }


    --[[--------------------------< F O R W A R D  D E C L A R A T I O N S >--------------------------------------
    --[[--------------------------< F O R W A R D  D E C L A R A T I O N S >--------------------------------------
    each of these counts against the Lua upvalue limit
    ]]
    ]]
    local dates, year_date_check -- functions in Module:Citation/CS1/Date_validation


    local cfg = {}; -- table of configuration tables that are defined in Module:Citation/CS1/Configuration
    local validation; -- functions in Module:Citation/CS1/Date_validation
    local whitelist = {}; -- table of tables listing valid template parameter names; defined in Module:Citation/CS1/Whitelist


    --[[--------------------------< I S _ S E T >------------------------------------------------------------------
    local utilities; -- functions in Module:Citation/CS1/Utilities
    local z ={}; -- table of tables in Module:Citation/CS1/Utilities


    Returns true if argument is set; false otherwise. Argument is 'set' when it exists (not nil) or when it is not an empty string.
    local identifiers; -- functions and tables in Module:Citation/CS1/Identifiers
    This function is global because it is called from both this module and from Date validation
    local metadata; -- functions in Module:Citation/CS1/COinS
    local cfg = {}; -- table of configuration tables that are defined in Module:Citation/CS1/Configuration
    local whitelist = {}; -- table of tables listing valid template parameter names; defined in Module:Citation/CS1/Whitelist


    --[[------------------< P A G E  S C O P E  V A R I A B L E S >---------------
    declare variables here that have page-wide scope that are not brought in from
    other modules; that are created here and used here
    ]]
    ]]
    function is_set( var )
    local added_deprecated_cat; -- Boolean flag so that the category is added only once
    return not (var == nil or var == '');
    local added_discouraged_cat; -- Boolean flag so that the category is added only once
    end
    local added_vanc_errs; -- Boolean flag so we only emit one Vancouver error / category
    local Frame; -- holds the module's frame table


    --[[--------------------------< F I R S T _ S E T >------------------------------------------------------------
    --[[--------------------------< F I R S T _ S E T >------------------------------------------------------------


    First set variable or nil if none
    Locates and returns the first set value in a table of values where the order established in the table,
    left-to-right (or top-to-bottom), is the order in which the values are evaluated.  Returns nil if none are set.
     
    This version replaces the original 'for _, val in pairs do' and a similar version that used ipairs.  With the pairs
    version the order of evaluation could not be guaranteed.  With the ipairs version, a nil value would terminate
    the for-loop before it reached the actual end of the list.


    ]]
    ]]


    local function first_set(...)
    local function first_set (list, count)
    local list = {...};
    local i = 1;
    for _, var in pairs(list) do
    while i <= count do -- loop through all items in list
    if is_set( var ) then
    if utilities.is_set( list[i] ) then
    return var;
    return list[i]; -- return the first set list member
    end
    end
    i = i + 1; -- point to next
    end
    end
    end
    end


    --[[--------------------------< I N _ A R R A Y >--------------------------------------------------------------


    Whether needle is in haystack
    --[[--------------------------< A D D _ V A N C _ E R R O R >----------------------------------------------------
     
    Adds a single Vancouver system error message to the template's output regardless of how many error actually exist.
    To prevent duplication, added_vanc_errs is nil until an error message is emitted.
     
    added_vanc_errs is a Boolean declared in page scope variables above


    ]]
    ]]


    local function in_array( needle, haystack )
    local function add_vanc_error (source, position)
    if needle == nil then
    if added_vanc_errs then return end
    return false;
    end
    added_vanc_errs = true; -- note that we've added this category
    for n,v in ipairs( haystack ) do
    table.insert( z.message_tail, { utilities.set_message ( 'err_vancouver', {source, position}, true ) } );
    if v == needle then
    return n;
    end
    end
    return false;
    end
    end


    --[[--------------------------< S U B S T I T U T E >----------------------------------------------------------


    Populates numbered arguments in a message string using an argument table.
    --[[--------------------------< I S _ S C H E M E >------------------------------------------------------------
     
    does this thing that purports to be a URI scheme seem to be a valid scheme?  The scheme is checked to see if it
    is in agreement with http://tools.ietf.org/html/std66#section-3.1 which says:
    Scheme names consist of a sequence of characters beginning with a
      letter and followed by any combination of letters, digits, plus
      ("+"), period ("."), or hyphen ("-").
     
    returns true if it does, else false


    ]]
    ]]


    local function substitute( msg, args )
    local function is_scheme (scheme)
    return args and mw.message.newRawMessage( msg, args ):plain() or msg;
    return scheme and scheme:match ('^%a[%a%d%+%.%-]*:'); -- true if scheme is set and matches the pattern
    end
    end


    --[[--------------------------< E R R O R _ C O M M E N T >----------------------------------------------------


    Wraps error messages with css markup according to the state of hidden.
    --[=[-------------------------< I S _ D O M A I N _ N A M E >--------------------------------------------------
     
    Does this thing that purports to be a domain name seem to be a valid domain name?
     
    Syntax defined here: http://tools.ietf.org/html/rfc1034#section-3.5
    BNF defined here: https://tools.ietf.org/html/rfc4234
    Single character names are generally reserved; see https://tools.ietf.org/html/draft-ietf-dnsind-iana-dns-01#page-15;
    see also [[Single-letter second-level domain]]
    list of TLDs: https://www.iana.org/domains/root/db
     
    RFC 952 (modified by RFC 1123) requires the first and last character of a hostname to be a letter or a digit.  Between
    the first and last characters the name may use letters, digits, and the hyphen.
     
    Also allowed are IPv4 addresses. IPv6 not supported
     
    domain is expected to be stripped of any path so that the last character in the last character of the TLD.  tld
    is two or more alpha characters.  Any preceding '//' (from splitting a URL with a scheme) will be stripped
    here.  Perhaps not necessary but retained in case it is necessary for IPv4 dot decimal.


    ]]
    There are several tests:
    local function error_comment( content, hidden )
    the first character of the whole domain name including subdomains must be a letter or a digit
    return substitute( hidden and cfg.presentation['hidden-error'] or cfg.presentation['visible-error'], content );
    internationalized domain name (ASCII characters with .xn-- ASCII Compatible Encoding (ACE) prefix xn-- in the TLD) see https://tools.ietf.org/html/rfc3490
    end
    single-letter/digit second-level domains in the .org, .cash, and .today TLDs
    q, x, and z SL domains in the .com TLD
    i and q SL domains in the .net TLD
    single-letter SL domains in the ccTLDs (where the ccTLD is two letters)
    two-character SL domains in gTLDs (where the gTLD is two or more letters)
    three-plus-character SL domains in gTLDs (where the gTLD is two or more letters)
    IPv4 dot-decimal address format; TLD not allowed


    --[[--------------------------< S E T _ E R R O R >--------------------------------------------------------------
    returns true if domain appears to be a proper name and TLD or IPv4 address, else false


    Sets an error condition and returns the appropriate error message.  The actual placement of the error message in the output is
    ]=]
    the responsibility of the calling function.


    ]]
    local function is_domain_name (domain)
    local function set_error( error_id, arguments, raw, prefix, suffix )
    if not domain then
    local error_state = cfg.error_conditions[ error_id ];
    return false; -- if not set, abandon
    end
    prefix = prefix or "";
    domain = domain:gsub ('^//', ''); -- strip '//' from domain name if present; done here so we only have to do it once
    suffix = suffix or "";
    if error_state == nil then
    if not domain:match ('^[%w]') then -- first character must be letter or digit
    error( cfg.messages['undefined_error'] );
    return false;
    elseif is_set( error_state.category ) then
    table.insert( z.error_categories, error_state.category );
    end
    end
     
    local message = substitute( error_state.message, arguments );
    if domain:match ('^%a+:') then -- hack to detect things that look like s:Page:Title where Page: is namespace at Wikisource
    return false;
    message = message .. " ([[" .. cfg.messages['help page link'] ..
    "#" .. error_state.anchor .. "|" ..
    cfg.messages['help page label'] .. "]])";
    z.error_ids[ error_id ] = true;
    if in_array( error_id, { 'bare_url_missing_title', 'trans_missing_title' } )
    and z.error_ids['citation_missing_title'] then
    return '', false;
    end
    end
    message = table.concat({ prefix, message, suffix });
    if raw == true then
    return message, error_state.hidden;
    end
    return error_comment( message, error_state.hidden );
    end


    --[[--------------------------< A D D _ M A I N T _ C A T >------------------------------------------------------
    local patterns = { -- patterns that look like URLs
    '%f[%w][%w][%w%-]+[%w]%.%a%a+$', -- three or more character hostname.hostname or hostname.tld
    '%f[%w][%w][%w%-]+[%w]%.xn%-%-[%w]+$', -- internationalized domain name with ACE prefix
    '%f[%a][qxz]%.com$', -- assigned one character .com hostname (x.com times out 2015-12-10)
    '%f[%a][iq]%.net$', -- assigned one character .net hostname (q.net registered but not active 2015-12-10)
    '%f[%w][%w]%.%a%a$', -- one character hostname and ccTLD (2 chars)
    '%f[%w][%w][%w]%.%a%a+$', -- two character hostname and TLD
    '^%d%d?%d?%.%d%d?%d?%.%d%d?%d?%.%d%d?%d?', -- IPv4 address
    }


    Adds a category to z.maintenance_cats using names from the configuration file with additional text if any.
    for _, pattern in ipairs (patterns) do -- loop through the patterns list
    To prevent duplication, the added_maint_cats table lists the categories by key that have been added to z.maintenance_cats.
    if domain:match (pattern) then
    return true; -- if a match then we think that this thing that purports to be a URL is a URL
    end
    end


    ]]
    for _, d in ipairs ({'cash', 'company', 'today', 'org'}) do -- look for single letter second level domain names for these top level domains
     
    if domain:match ('%f[%w][%w]%.' .. d) then
    local added_maint_cats = {} -- list of maintenance categories that have been added to z.maintenance_cats
    return true
    local function add_maint_cat (key, arguments)
    end
    if not added_maint_cats [key] then
    added_maint_cats [key] = true; -- note that we've added this category
    table.insert( z.maintenance_cats, substitute (cfg.maint_cats [key], arguments)); -- make name then add to table
    end
    end
    return false; -- no matches, we don't know what this thing is
    end
    end


    --[[--------------------------< A D D _ P R O P _ C A T >--------------------------------------------------------


    Adds a category to z.properties_cats using names from the configuration file with additional text if any.
    --[[--------------------------< I S _ U R L >------------------------------------------------------------------
     
    returns true if the scheme and domain parts of a URL appear to be a valid URL; else false.
     
    This function is the last step in the validation process.  This function is separate because there are cases that
    are not covered by split_url(), for example is_parameter_ext_wikilink() which is looking for bracketted external
    wikilinks.


    ]]
    ]]


    local added_prop_cats = {} -- list of property categories that have been added to z.properties_cats
    local function is_url (scheme, domain)
    local function add_prop_cat (key, arguments)
    if utilities.is_set (scheme) then -- if scheme is set check it and domain
    if not added_prop_cats [key] then
    return is_scheme (scheme) and is_domain_name (domain);
    added_prop_cats [key] = true; -- note that we've added this category
    else
    table.insert( z.properties_cats, substitute (cfg.prop_cats [key], arguments)); -- make name then add to table
    return is_domain_name (domain); -- scheme not set when URL is protocol-relative
    end
    end
    end
    end


    --[[--------------------------< A D D _ V A N C _ E R R O R >----------------------------------------------------


    Adds a single Vancouver system error message to the template's output regardless of how many error actually exist.
    --[[--------------------------< S P L I T _ U R L >------------------------------------------------------------
    To prevent duplication, added_vanc_errs is nil until an error message is emitted.


    ]]
    Split a URL into a scheme, authority indicator, and domain.


    local added_vanc_errs; -- flag so we only emit one Vancouver error / category
    First remove Fully Qualified Domain Name terminator (a dot following TLD) (if any) and any path(/), query(?) or fragment(#).
    local function add_vanc_error ()
    if not added_vanc_errs then
    added_vanc_errs = true; -- note that we've added this category
    table.insert( z.message_tail, { set_error( 'vancouver', {}, true ) } );
    end
    end


    --[[--------------------------< C H E C K _ U R L >------------------------------------------------------------
    If protocol-relative URL, return nil scheme and domain else return nil for both scheme and domain.


    Determines whether a URL string is valid.
    When not protocol-relative, get scheme, authority indicator, and domain.  If there is an authority indicator (one
    or more '/' characters immediately following the scheme's colon), make sure that there are only 2.


    At present the only check is whether the string appears to be prefixed with a URI scheme.  It is not determined whether
    Any URL that does not have news: scheme must have authority indicator (//).  TODO: are there other common schemes
    the URI scheme is valid or whether the URL is otherwise well formed.
    like news: that don't use authority indicator?


    The scheme is checked http://tools.ietf.org/html/std66#section-3.1 which says:
    Strip off any port and path;
    Scheme names consist of a sequence of characters beginning with a
      letter and followed by any combination of letters, digits, plus
      ("+"), period ("."), or hyphen ("-").


    First we test for space characters.  If any are found, return false.  Then test for the case where the url is
    protocol relative (//example.com).  If the first two characters of the |url= value are //, return true.  Last
    look for what appears to be a scheme according to the definition above.  If the characters preceding the colon
    are in the allowed set, return true, else false
    ]]
    ]]


    local function check_url( url_str )
    local function split_url (url_str)
    if nil == url_str:match ("^%S+$") then -- if there are any spaces in |url=value
    local scheme, authority, domain;
    return false;
    url_str = url_str:gsub ('([%a%d])%.?[/%?#].*$', '%1'); -- strip FQDN terminator and path(/), query(?), fragment (#) (the capture prevents false replacement of '//')
     
    if url_str:match ('^//%S*') then -- if there is what appears to be a protocol-relative URL
    domain = url_str:match ('^//(%S*)')
    elseif url_str:match ('%S-:/*%S+') then -- if there is what appears to be a scheme, optional authority indicator, and domain name
    scheme, authority, domain = url_str:match ('(%S-:)(/*)(%S+)'); -- extract the scheme, authority indicator, and domain portions
    if utilities.is_set (authority) then
    authority = authority:gsub ('//', '', 1); -- replace place 1 pair of '/' with nothing;
    if utilities.is_set(authority) then -- if anything left (1 or 3+ '/' where authority should be) then
    return scheme; -- return scheme only making domain nil which will cause an error message
    end
    else
    if not scheme:match ('^news:') then -- except for news:..., MediaWiki won't link URLs that do not have authority indicator; TODO: a better way to do this test?
    return scheme; -- return scheme only making domain nil which will cause an error message
    end
    end
    domain = domain:gsub ('(%a):%d+', '%1'); -- strip port number if present
    end
    end
    return url_str:sub(1,2) == "//" or nil ~= url_str:match ("^%a[%a%d%+%.%-]*:") -- protocol relative or scheme part composed of legitimate characters
    return scheme, domain;
    end
    end


    --[[--------------------------< S A F E _ F O R _ I T A L I C S >----------------------------------------------


    Protects a string that will be wrapped in wiki italic markup '' ... ''
    --[[--------------------------< L I N K _ P A R A M _ O K >---------------------------------------------------


    Note: We cannot use <i> for italics, as the expected behavior for italics specified by ''...'' in the title is that
    checks the content of |title-link=, |series-link=, |author-link=, etc. for properly formatted content: no wikilinks, no URLs
    they will be inverted (i.e. unitalicized) in the resulting references.  In addition, <i> and '' tend to interact
     
    poorly under Mediawiki's HTML tidy.
    Link parameters are to hold the title of a Wikipedia article, so none of the WP:TITLESPECIALCHARACTERS are allowed:
    # < > [ ] | { } _
    except the underscore which is used as a space in wiki URLs and # which is used for section links
     
    returns false when the value contains any of these characters.
     
    When there are no illegal characters, this function returns TRUE if value DOES NOT appear to be a valid URL (the
    |<param>-link= parameter is ok); else false when value appears to be a valid URL (the |<param>-link= parameter is NOT ok).


    ]]
    ]]


    local function safe_for_italics( str )
    local function link_param_ok (value)
    if not is_set(str) then
    local scheme, domain;
    return str;
    if value:find ('[<>%[%]|{}]') then -- if any prohibited characters
    else
    return false;
    if str:sub(1,1) == "'" then str = "<span />" .. str; end
    if str:sub(-1,-1) == "'" then str = str .. "<span />"; end
    -- Remove newlines as they break italics.
    return str:gsub( '\n', ' ' );
    end
    end
    scheme, domain = split_url (value); -- get scheme or nil and domain or nil from URL;
    return not is_url (scheme, domain); -- return true if value DOES NOT appear to be a valid URL
    end
    end


    --[[--------------------------< S A F E _ F O R _ U R L >------------------------------------------------------


    Escape sequences for content that will be used for URL descriptions
    --[[--------------------------< L I N K _ T I T L E _ O K >---------------------------------------------------


    ]]
    Use link_param_ok() to validate |<param>-link= value and its matching |<title>= value.
     
    local function safe_for_url( str )
    if str:match( "%[%[.-%]%]" ) ~= nil then
    table.insert( z.message_tail, { set_error( 'wikilink_in_url', {}, true ) } );
    end
    return str:gsub( '[%[%]\n]', {
    ['['] = '&#91;',
    [']'] = '&#93;',
    ['\n'] = ' ' } );
    end


    --[[--------------------------< W R A P _ S T Y L E >----------------------------------------------------------
    |<title>= may be wiki-linked but not when |<param>-link= has a value.  This function emits an error message when
    that condition exists


    Applies styling to various parameters.  Supplied string is wrapped using a message_list configuration taking one
    check <link> for inter-language interwiki-link prefix.  prefix must be a MediaWiki-recognized language
    argument; protects italic styled parameters.  Additional text taken from citation_config.presentation - the reason
    code and must begin with a colon.
    this function is similar to but separate from wrap_msg().


    ]]
    ]]


    local function wrap_style (key, str)
    local function link_title_ok (link, lorig, title, torig)
    if not is_set( str ) then
    local orig;
    return "";
    if utilities.is_set (link) then -- don't bother if <param>-link doesn't have a value
    elseif in_array( key, { 'italic-title', 'trans-italic-title' } ) then
    if not link_param_ok (link) then -- check |<param>-link= markup
    str = safe_for_italics( str );
    orig = lorig; -- identify the failing link parameter
    elseif title:find ('%[%[') then -- check |title= for wikilink markup
    orig = torig; -- identify the failing |title= parameter
    elseif link:match ('^%a+:') then -- if the link is what looks like an interwiki
    local prefix = link:match ('^(%a+):'):lower(); -- get the interwiki prefix
     
    if cfg.inter_wiki_map[prefix] then -- if prefix is in the map, must have preceding colon
    orig = lorig; -- flag as error
    end
    end
    end
    end


    return substitute( cfg.presentation[key], {str} );
    if utilities.is_set (orig) then
    link = ''; -- unset
    table.insert( z.message_tail, { utilities.set_message ( 'err_bad_paramlink', orig)}); -- URL or wikilink in |title= with |title-link=;
    end
    return link; -- link if ok, empty string else
    end
    end


    --[[--------------------------< E X T E R N A L _ L I N K >----------------------------------------------------


    Format an external link with error checking
    --[[--------------------------< C H E C K _ U R L >------------------------------------------------------------
     
    Determines whether a URL string appears to be valid.
     
    First we test for space characters.  If any are found, return false.  Then split the URL into scheme and domain
    portions, or for protocol-relative (//example.com) URLs, just the domain.  Use is_url() to validate the two
    portions of the URL.  If both are valid, or for protocol-relative if domain is valid, return true, else false.
     
    Because it is different from a standard URL, and because this module used external_link() to make external links
    that work for standard and news: links, we validate newsgroup names here.  The specification for a newsgroup name
    is at https://tools.ietf.org/html/rfc5536#section-3.1.4


    ]]
    ]]


    local function external_link( URL, label, source )
    local function check_url( url_str )
    local error_str = "";
    if nil == url_str:match ("^%S+$") then -- if there are any spaces in |url=value it can't be a proper URL
    if not is_set( label ) then
    return false;
    label = URL;
    if is_set( source ) then
    error_str = set_error( 'bare_url_missing_title', { wrap_style ('parameter', source) }, false, " " );
    else
    error( cfg.messages["bare_url_no_origin"] );
    end
    end
    end
    if not check_url( URL ) then
    local scheme, domain;
    error_str = set_error( 'bad_url', {}, false, " " ) .. error_str;
     
    scheme, domain = split_url (url_str); -- get scheme or nil and domain or nil from URL;
    if 'news:' == scheme then -- special case for newsgroups
    return domain:match('^[%a%d%+%-_]+%.[%a%d%+%-_%.]*[%a%d%+%-_]$');
    end
    end
    return table.concat({ "[", URL, " ", safe_for_url( label ), "]", error_str });
    return is_url (scheme, domain); -- return true if value appears to be a valid URL
    end
    end


    --[[--------------------------< E X T E R N A L _ L I N K _ I D >----------------------------------------------


    Formats a wiki style external link
    --[=[-------------------------< I S _ P A R A M E T E R _ E X T _ W I K I L I N K >----------------------------


    ]]
    Return true if a parameter value has a string that begins and ends with square brackets [ and ] and the first
    non-space characters following the opening bracket appear to be a URL.  The test will also find external wikilinks
    that use protocol-relative URLs. Also finds bare URLs.


    local function external_link_id(options)
    The frontier pattern prevents a match on interwiki-links which are similar to scheme:path URLs. The tests that
    local url_string = options.id;
    find bracketed URLs are required because the parameters that call this test (currently |title=, |chapter=, |work=,
    if options.encode == true or options.encode == nil then
    and |publisher=) may have wikilinks and there are articles or redirects like '//Hus' so, while uncommon, |title=[[//Hus]]
    url_string = mw.uri.encode( url_string );
    is possible as might be [[en://Hus]].
    end
    return mw.ustring.format( '[[%s|%s]]%s[%s%s%s %s]',
    options.link, options.label, options.separator or "&nbsp;",
    options.prefix, url_string, options.suffix or "",
    mw.text.nowiki(options.id)
    );
    end


    --[[--------------------------< D E P R E C A T E D _ P A R A M E T E R >--------------------------------------
    ]=]


    Categorize and emit an error message when the citation contains one or more deprecated parameters.  The function includes the
    local function is_parameter_ext_wikilink (value)
    offending parameter name to the error message.  Only one error message is emitted regardless of the number of deprecated
    local scheme, domain;
    parameters in the citation.


    ]]
    if value:match ('%f[%[]%[%a%S*:%S+.*%]') then -- if ext. wikilink with scheme and domain: [xxxx://yyyyy.zzz]
    scheme, domain = split_url (value:match ('%f[%[]%[(%a%S*:%S+).*%]'));
    elseif value:match ('%f[%[]%[//%S+.*%]') then -- if protocol-relative ext. wikilink: [//yyyyy.zzz]
    scheme, domain = split_url (value:match ('%f[%[]%[(//%S+).*%]'));
    elseif value:match ('%a%S*:%S+') then -- if bare URL with scheme; may have leading or trailing plain text
    scheme, domain = split_url (value:match ('(%a%S*:%S+)'));
    elseif value:match ('//%S+') then -- if protocol-relative bare URL: //yyyyy.zzz; may have leading or trailing plain text
    scheme, domain = split_url (value:match ('(//%S+)')); -- what is left should be the domain
    else
    return false; -- didn't find anything that is obviously a URL
    end


    local page_in_deprecated_cat; -- sticky flag so that the category is added only once
    return is_url (scheme, domain); -- return true if value appears to be a valid URL
    local function deprecated_parameter(name)
    if not page_in_deprecated_cat then
    page_in_deprecated_cat = true; -- note that we've added this category
    table.insert( z.message_tail, { set_error( 'deprecated_params', {name}, true ) } ); -- add error message
    end
    end
    end


    --[[--------------------------< K E R N _ Q U O T E S >--------------------------------------------------------


    Apply kerning to open the space between the quote mark provided by the Module and a leading or trailing quote mark contained in a |title= or |chapter= parameter's value.
    --[[-------------------------< C H E C K _ F O R _ U R L >-----------------------------------------------------
    This function will positive kern either single or double quotes:
    "'Unkerned title with leading and trailing single quote marks'"
    " 'Kerned title with leading and trailing single quote marks' " (in real life the kerning isn't as wide as this example)
    Double single quotes (italic or bold wikimarkup) are not kerned.


    Call this function for chapter titles, for website titles, etc; not for book titles.
    loop through a list of parameters and their values.  Look at the value and if it has an external link, emit an error message.


    ]]
    ]]


    local function kern_quotes (str)
    local function check_for_url (parameter_list)
    local cap='';
    local error_message = '';
    local cap2='';
    for k, v in pairs (parameter_list) do -- for each parameter in the list
    if is_parameter_ext_wikilink (v) then -- look at the value; if there is a URL add an error message
    cap, cap2 = str:match ("^([\"\'])([^\'].+)"); -- match leading double or single quote but not double single quotes
    if utilities.is_set(error_message) then -- once we've added the first portion of the error message ...
    if is_set (cap) then
    error_message = error_message .. ", "; -- ... add a comma space separator
    str = substitute (cfg.presentation['kern-left'], {cap, cap2});
    end
    error_message = error_message .. "&#124;" .. k .. "="; -- add the failed parameter
    end
    end
    end
     
    if utilities.is_set (error_message) then -- done looping, if there is an error message, display it
    cap, cap2 = str:match ("^(.+[^\'])([\"\'])$")
    table.insert( z.message_tail, { utilities.set_message ( 'err_param_has_ext_link', {error_message}, true ) } );
    if is_set (cap) then
    str = substitute (cfg.presentation['kern-right'], {cap, cap2});
    end
    end
    return str;
    end
    end


    --[[--------------------------< F O R M A T _ S C R I P T _ V A L U E >----------------------------------------


    |script-title= holds title parameters that are not written in Latin based scripts: Chinese, Japanese, Arabic, Hebrew, etc. These scripts should
    --[[--------------------------< S A F E _ F O R _ U R L >------------------------------------------------------
    not be italicized and may be written right-to-left.  The value supplied by |script-title= is concatenated onto Title after Title has been wrapped
    in italic markup.


    Regardless of language, all values provided by |script-title= are wrapped in <bdi>...</bdi> tags to isolate rtl languages from the English left to right.
    Escape sequences for content that will be used for URL descriptions
     
    ]]
     
    local function safe_for_url( str )
    if str:match( "%[%[.-%]%]" ) ~= nil then
    table.insert( z.message_tail, { utilities.set_message ( 'err_wikilink_in_url', {}, true ) } );
    end
    return str:gsub( '[%[%]\n]', {
    ['['] = '&#91;',
    [']'] = '&#93;',
    ['\n'] = ' ' } );
    end


    |script-title= provides a unique feature.  The value in |script-title= may be prefixed with a two-character ISO639-1 language code and a colon:
    |script-title=ja:*** *** (where * represents a Japanese character)
    Spaces between the two-character code and the colon and the colon and the first script character are allowed:
    |script-title=ja : *** ***
    |script-title=ja: *** ***
    |script-title=ja :*** ***
    Spaces preceding the prefix are allowed: |script-title = ja:*** ***


    The prefix is checked for validity.  If it is a valid ISO639-1 language code, the lang attribute (lang="ja") is added to the <bdi> tag so that browsers can
    --[[--------------------------< E X T E R N A L _ L I N K >----------------------------------------------------
    know the language the tag contains.  This may help the browser render the script more correctly.  If the prefix is invalid, the lang attribute
    is not added.  At this time there is no error message for this condition.


    Supports |script-title= and |script-chapter=
    Format an external link with error checking


    TODO: error messages when prefix is invalid ISO639-1 code; when script_value has prefix but no script;
    ]]
    ]]


    local function format_script_value (script_value)
    local function external_link( URL, label, source, access)
    local lang=''; -- initialize to empty string
    local error_str = "";
    local name;
    local domain;
    if script_value:match('^%l%l%s*:') then -- if first 3 non-space characters are script language prefix
    local path;
    lang = script_value:match('^(%l%l)%s*:%s*%S.*'); -- get the language prefix or nil if there is no script
    local base_url;
    if not is_set (lang) then
     
    return ''; -- script_value was just the prefix so return empty string
    if not utilities.is_set ( label ) then
    end
    label = URL;
    -- if we get this far we have prefix and script
    if utilities.is_set ( source ) then
    name = mw.language.fetchLanguageName( lang, "en" ); -- get language name so that we can use it to categorize
    error_str = utilities.set_message ( 'err_bare_url_missing_title', { utilities.wrap_style ('parameter', source) }, false, " " );
    if is_set (name) then -- is prefix a proper ISO 639-1 language code?
    else
    script_value = script_value:gsub ('^%l%l%s*:%s*', ''); -- strip prefix from script
    error( cfg.messages["bare_url_no_origin"] );
    -- is prefix one of these language codes?
    end
    if in_array (lang, {'ar', 'bg', 'bs', 'dv', 'el', 'fa', 'he', 'hy', 'ja', 'ka', 'ko', 'ku', 'mk', 'ps', 'ru', 'sd', 'sr', 'th', 'uk', 'ug', 'yi', 'zh'}) then
    end
    add_prop_cat ('script_with_name', {name, lang})
    if not check_url( URL ) then
    else
    error_str = utilities.set_message ( 'err_bad_url', {utilities.wrap_style ('parameter', source)}, false, " " ) .. error_str;
    add_prop_cat ('script')
    end
    end
    lang = ' lang="' .. lang .. '" '; -- convert prefix into a lang attribute
    domain, path = URL:match ('^([/%.%-%+:%a%d]+)([/%?#].*)$'); -- split the URL into scheme plus domain and path
    else
    if path then -- if there is a path portion
    lang = ''; -- invalid so set lang to empty string
    path = path:gsub ('[%[%]]', {['['] = '%5b', [']'] = '%5d'}); -- replace '[' and ']' with their percent-encoded values
    end
    URL = table.concat ({domain, path}); -- and reassemble
    end
    end
    script_value = substitute (cfg.presentation['bdi'], {lang, script_value}); -- isolate in case script is rtl


    return script_value;
    base_url = table.concat({ "[", URL, " ", safe_for_url (label), "]" }); -- assemble a wiki-markup URL
    end
     
    --[[--------------------------< S C R I P T _ C O N C A T E N A T E >------------------------------------------
     
    Initially for |title= and |script-title=, this function concatenates those two parameter values after the script value has been
    wrapped in <bdi> tags.
    ]]


    local function script_concatenate (title, script)
    if utilities.is_set (access) then -- access level (subscription, registration, limited)
    if is_set (script) then
    base_url = utilities.substitute (cfg.presentation['ext-link-access-signal'], {cfg.presentation[access].class, cfg.presentation[access].title, base_url}); -- add the appropriate icon
    script = format_script_value (script); -- <bdi> tags, lang atribute, categorization, etc; returns empty string on error
    if is_set (script) then
    title = title .. ' ' .. script; -- concatenate title and script title
    end
    end
    end
    return title;
    return table.concat ({base_url, error_str});
    end
    end




    --[[--------------------------< W R A P _ M S G >--------------------------------------------------------------
    --[[--------------------------< D E P R E C A T E D _ P A R A M E T E R >--------------------------------------


    Applies additional message text to various parameter values. Supplied string is wrapped using a message_list
    Categorize and emit an error message when the citation contains one or more deprecated parameters.  The function includes the
    configuration taking one argument.  Supports lower case text for {{citation}} templates. Additional text taken
    offending parameter name to the error message. Only one error message is emitted regardless of the number of deprecated
    from citation_config.messages - the reason this function is similar to but separate from wrap_style().
    parameters in the citation.
     
    added_deprecated_cat is a Boolean declared in page scope variables above


    ]]
    ]]


    local function wrap_msg (key, str, lower)
    local function deprecated_parameter(name)
    if not is_set( str ) then
    if not added_deprecated_cat then
    return "";
    added_deprecated_cat = true; -- note that we've added this category
    table.insert( z.message_tail, { utilities.set_message ( 'err_deprecated_params', {name}, true ) } ); -- add error message
    end
    end
    if true == lower then
    local msg;
    msg = cfg.messages[key]:lower(); -- set the message to lower case before
    str = substitute( msg, {str} ); -- including template text
    return str;
    else
    return substitute( cfg.messages[key], {str} );
    end
    end
    end


    --[[--------------------------< S E L E C T _ O N E >----------------------------------------------------------


    Chooses one matching parameter from a list of parameters to consider
    --[[--------------------------< D I S C O U R A G E D _ P A R A M E T E R >------------------------------------
    Generates an error if more than one match is present.
     
    Categorize and emit an maintenance message when the citation contains one or more discouraged parameters.  Only
    one error message is emitted regardless of the number of discouraged parameters in the citation.
     
    added_discouraged_cat is a Boolean declared in page scope variables above


    ]]
    ]]


    local function select_one( args, possible, error_condition, index )
    local function discouraged_parameter(name)
    local value = nil;
    if not added_discouraged_cat then
    local selected = '';
    added_discouraged_cat = true; -- note that we've added this category
    local error_list = {};
    table.insert( z.message_tail, { utilities.set_message ( 'maint_discouraged', {name}, true ) } ); -- add maint message
    if index ~= nil then index = tostring(index); end
    -- Handle special case of "#" replaced by empty string
    if index == '1' then
    for _, v in ipairs( possible ) do
    v = v:gsub( "#", "" );
    if is_set(args[v]) then
    if value ~= nil and selected ~= v then
    table.insert( error_list, v );
    else
    value = args[v];
    selected = v;
    end
    end
    end
    end
    end
    end
    for _, v in ipairs( possible ) do
     
    if index ~= nil then
     
    v = v:gsub( "#", index );
    --[=[-------------------------< K E R N _ Q U O T E S >--------------------------------------------------------
    end
     
    if is_set(args[v]) then
    Apply kerning to open the space between the quote mark provided by the module and a leading or trailing quote
    if value ~= nil and selected ~=  v then
    mark contained in a |title= or |chapter= parameter's value.
    table.insert( error_list, v );
     
    else
    This function will positive kern either single or double quotes:
    value = args[v];
    "'Unkerned title with leading and trailing single quote marks'"
    selected = v;
    " 'Kerned title with leading and trailing single quote marks' " (in real life the kerning isn't as wide as this example)
    end
    Double single quotes (italic or bold wiki-markup) are not kerned.
     
    Replaces Unicode quote marks in plain text or in the label portion of a [[L|D]] style wikilink with typewriter
    quote marks regardless of the need for kerning.  Unicode quote marks are not replaced in simple [[D]] wikilinks.
     
    Call this function for chapter titles, for website titles, etc.; not for book titles.
     
    ]=]
     
    local function kern_quotes (str)
    local cap = '';
    local cap2 = '';
    local wl_type, label, link;
     
    wl_type, label, link = utilities.is_wikilink (str); -- wl_type is: 0, no wl (text in label variable); 1, [[D]]; 2, [[L|D]]
    if 1 == wl_type then -- [[D]] simple wikilink with or without quote marks
    if mw.ustring.match (str, '%[%[[\"“”\'‘’].+[\"“”\'‘’]%]%]') then -- leading and trailing quote marks
    str = utilities.substitute (cfg.presentation['kern-wl-both'], str);
    elseif mw.ustring.match (str, '%[%[[\"“”\'‘’].+%]%]') then -- leading quote marks
    str = utilities.substitute (cfg.presentation['kern-wl-left'], str);
    elseif mw.ustring.match (str, '%[%[.+[\"“”\'‘’]%]%]') then -- trailing quote marks
    str = utilities.substitute (cfg.presentation['kern-wl-right'], str);
    end
     
    else -- plain text or [[L|D]]; text in label variable
    label = mw.ustring.gsub (label, '[“”]', '\"'); -- replace “” (U+201C & U+201D) with " (typewriter double quote mark)
    label = mw.ustring.gsub (label, '[‘’]', '\''); -- replace ‘’ (U+2018 & U+2019) with ' (typewriter single quote mark)
     
    cap, cap2 = mw.ustring.match (label, "^([\"\'])([^\'].+)"); -- match leading double or single quote but not doubled single quotes (italic markup)
    if utilities.is_set (cap) then
    label = utilities.substitute (cfg.presentation['kern-left'], {cap, cap2});
    end
    end
    end
    if #error_list > 0 then
    cap, cap2 = mw.ustring.match (label, "^(.+[^\'])([\"\'])$") -- match trailing double or single quote but not doubled single quotes (italic markup)
    local error_str = "";
    if utilities.is_set (cap) then
    for _, k in ipairs( error_list ) do
    label = utilities.substitute (cfg.presentation['kern-right'], {cap, cap2});
    if error_str ~= "" then error_str = error_str .. cfg.messages['parameter-separator'] end
    error_str = error_str .. wrap_style ('parameter', k);
    end
    end
    if #error_list > 1 then
    error_str = error_str .. cfg.messages['parameter-final-separator'];
    if 2 == wl_type then
    str = utilities.make_wikilink (link, label); -- reassemble the wikilink
    else
    else
    error_str = error_str .. cfg.messages['parameter-pair-separator'];
    str = label;
    end
    end
    error_str = error_str .. wrap_style ('parameter', selected);
    table.insert( z.message_tail, { set_error( error_condition, {error_str}, true ) } );
    end
    end
    return str;
    return value, selected;
    end
    end


    --[[--------------------------< F O R M A T _ C H A P T E R _ T I T L E >--------------------------------------


    Format the four chapter parameters: |script-chapter=, |chapter=, |trans-chapter=, and |chapter-url= into a single Chapter meta-
    --[[--------------------------< F O R M A T _ S C R I P T _ V A L U E >----------------------------------------
    parameter (chapter_url_source used for error messages).
     
    |script-title= holds title parameters that are not written in Latin-based scripts: Chinese, Japanese, Arabic, Hebrew, etc. These scripts should
    not be italicized and may be written right-to-left.  The value supplied by |script-title= is concatenated onto Title after Title has been wrapped
    in italic markup.


    ]]
    Regardless of language, all values provided by |script-title= are wrapped in <bdi>...</bdi> tags to isolate RTL languages from the English left to right.


    local function format_chapter_title (scriptchapter, chapter, transchapter, chapterurl, chapter_url_source)
    |script-title= provides a unique feature.  The value in |script-title= may be prefixed with a two-character ISO 639-1 language code and a colon:
    local chapter_error = '';
    |script-title=ja:*** *** (where * represents a Japanese character)
    Spaces between the two-character code and the colon and the colon and the first script character are allowed:
    if not is_set (chapter) then
    |script-title=ja : *** ***
    chapter = ''; -- to be safe for concatenation
    |script-title=ja: *** ***
    else
    |script-title=ja :*** ***
    chapter = kern_quotes (chapter); -- if necessary, separate chapter title's leading and trailing quote marks from Module provided quote marks
    Spaces preceding the prefix are allowed: |script-title = ja:*** ***
    chapter = wrap_style ('quoted-title', chapter);
     
    end
    The prefix is checked for validity.  If it is a valid ISO 639-1 language code, the lang attribute (lang="ja") is added to the <bdi> tag so that browsers can
    know the language the tag contains.  This may help the browser render the script more correctly.  If the prefix is invalid, the lang attribute
    is not added.  At this time there is no error message for this condition.


    chapter = script_concatenate (chapter, scriptchapter) -- <bdi> tags, lang atribute, categorization, etc; must be done after title is wrapped
    Supports |script-title=, |script-chapter=, |script-<periodical>=


    if is_set (transchapter) then
    ]]
    transchapter = wrap_style ('trans-quoted-title', transchapter);
     
    if is_set (chapter) then
    local function format_script_value (script_value, script_param)
    chapter = chapter .. ' ' .. transchapter;
    local lang=''; -- initialize to empty string
    else -- here when transchapter without chapter or script-chapter
    local name;
    chapter = transchapter; --  
    if script_value:match('^%l%l%l?%s*:') then -- if first 3 or 4 non-space characters are script language prefix
    chapter_error = ' ' .. set_error ('trans_missing_title', {'chapter'});
    lang = script_value:match('^(%l%l%l?)%s*:%s*%S.*'); -- get the language prefix or nil if there is no script
    if not utilities.is_set (lang) then
    table.insert( z.message_tail, { utilities.set_message ( 'err_script_parameter', {script_param, 'missing title part'}, true ) } ); -- prefix without 'title'; add error message
    return ''; -- script_value was just the prefix so return empty string
    end
    -- if we get this far we have prefix and script
    name = cfg.lang_code_remap[lang] or mw.language.fetchLanguageName( lang, cfg.this_wiki_code ); -- get language name so that we can use it to categorize
    if utilities.is_set (name) then -- is prefix a proper ISO 639-1 language code?
    script_value = script_value:gsub ('^%l+%s*:%s*', ''); -- strip prefix from script
    -- is prefix one of these language codes?
    if utilities.in_array (lang, cfg.script_lang_codes) then
    utilities.add_prop_cat ('script_with_name', {name, lang})
    else
    table.insert( z.message_tail, { utilities.set_message ( 'err_script_parameter', {script_param, 'unknown language code'}, true ) } ); -- unknown script-language; add error message
    end
    lang = ' lang="' .. lang .. '" '; -- convert prefix into a lang attribute
    else
    table.insert( z.message_tail, { utilities.set_message ( 'err_script_parameter', {script_param, 'invalid language code'}, true ) } ); -- invalid language code; add error message
    lang = ''; -- invalid so set lang to empty string
    end
    end
    else
    table.insert( z.message_tail, { utilities.set_message ( 'err_script_parameter', {script_param, 'missing prefix'}, true ) } ); -- no language code prefix; add error message
    end
    end
    script_value = utilities.substitute (cfg.presentation['bdi'], {lang, script_value}); -- isolate in case script is RTL


    if is_set (chapterurl) then
    return script_value;
    chapter = external_link (chapterurl, chapter, chapter_url_source); -- adds bare_url_missing_title error if appropriate
    end
     
    return chapter .. chapter_error;
    end
    end




    --[[
    --[[--------------------------< S C R I P T _ C O N C A T E N A T E >------------------------------------------
    Argument wrapper.  This function provides support for argument
     
    mapping defined in the configuration file so that multiple names
    Initially for |title= and |script-title=, this function concatenates those two parameter values after the script value has been
    can be transparently aliased to single internal variable.
    wrapped in <bdi> tags.
    ]]
    ]]


    local function argument_wrapper( args )
    local function script_concatenate (title, script, script_param)
    local origin = {};
    if utilities.is_set (script) then
    script = format_script_value (script, script_param); -- <bdi> tags, lang attribute, categorization, etc.; returns empty string on error
    return setmetatable({
    if utilities.is_set (script) then
    ORIGIN = function( self, k )
    title = title .. ' ' .. script; -- concatenate title and script title
    local dummy = self[k]; --force the variable to be loaded.
    return origin[k];
    end
    end
    },
    end
    {
    return title;
    __index = function ( tbl, k )
    end
    if origin[k] ~= nil then
     
    return nil;
     
    end
    --[[--------------------------< W R A P _ M S G >--------------------------------------------------------------
     
    local args, list, v = args, cfg.aliases[k];
    Applies additional message text to various parameter values. Supplied string is wrapped using a message_list
    configuration taking one argument.  Supports lower case text for {{citation}} templates.  Additional text taken
    if type( list ) == 'table' then
    from citation_config.messages - the reason this function is similar to but separate from wrap_style().
    v, origin[k] = select_one( args, list, 'redundant_parameters' );
    if origin[k] == nil then
    origin[k] = ''; -- Empty string, not nil
    end
    elseif list ~= nil then
    v, origin[k] = args[list], list;
    else
    -- maybe let through instead of raising an error?
    -- v, origin[k] = args[k], k;
    error( cfg.messages['unknown_argument_map'] );
    end
    -- Empty strings, not nil;
    if v == nil then
    v = cfg.defaults[k] or '';
    origin[k] = '';
    end
    tbl = rawset( tbl, k, v );
    return v;
    end,
    });
    end


    --[[
    Looks for a parameter's name in the whitelist.
    Parameters in the whitelist can have three values:
    true - active, supported parameters
    false - deprecated, supported parameters
    nil - unsupported parameters
    ]]
    ]]


    local function validate( name )
    local function wrap_msg (key, str, lower)
    local name = tostring( name );
    if not utilities.is_set ( str ) then
    local state = whitelist.basic_arguments[ name ];
    return "";
    -- Normal arguments
    if true == state then return true; end -- valid actively supported parameter
    if false == state then
    deprecated_parameter (name); -- parameter is deprecated but still supported
    return true;
    end
    end
    if true == lower then
    -- Arguments with numbers in them
    local msg;
    name = name:gsub( "%d+", "#" ); -- replace digit(s) with # (last25 becomes last#
    msg = cfg.messages[key]:lower(); -- set the message to lower case before
    state = whitelist.numbered_arguments[ name ];
    return utilities.substitute ( msg, str ); -- including template text
    if true == state then return true; end -- valid actively supported parameter
    else
    if false == state then
    return utilities.substitute ( cfg.messages[key], str );
    deprecated_parameter (name); -- parameter is deprecated but still supported
    end
    return true;
    end
    return false; -- Not supported because not found or name is set to nil
    end
    end




    -- Formats a wiki style internal link
    --[[----------------< W I K I S O U R C E _ U R L _ M A K E >-------------------
    local function internal_link_id(options)
    return mw.ustring.format( '[[%s|%s]]%s[[%s%s%s|%s]]',
    options.link, options.label, options.separator or "&nbsp;",
    options.prefix, options.id, options.suffix or "",
    mw.text.nowiki(options.id)
    );
    end


    Makes a Wikisource URL from Wikisource interwiki-link.  Returns the URL and appropriate
    label; nil else.


    --[[--------------------------< N O W R A P _ D A T E >--------------------------------------------------------
    str is the value assigned to |chapter= (or aliases) or |title= or |title-link=


    When date is YYYY-MM-DD format wrap in nowrap span: <span ...>YYYY-MM-DD</span>.  When date is DD MMMM YYYY or is
    ]]
    MMMM DD, YYYY then wrap in nowrap span: <span ...>DD MMMM</span> YYYY or <span ...>MMMM DD,</span> YYYY


    DOES NOT yet support MMMM YYYY or any of the date ranges.
    local function wikisource_url_make (str)
    local wl_type, D, L;
    local ws_url, ws_label;
    local wikisource_prefix = table.concat ({'https://', cfg.this_wiki_code, '.wikisource.org/wiki/'});


    ]]
    wl_type, D, L = utilities.is_wikilink (str); -- wl_type is 0 (not a wikilink), 1 (simple wikilink), 2 (complex wikilink)


    local function nowrap_date (date)
    if 0 == wl_type then -- not a wikilink; might be from |title-link=
    local cap='';
    str = D:match ('^[Ww]ikisource:(.+)') or D:match ('^[Ss]:(.+)'); -- article title from interwiki link with long-form or short-form namespace
    local cap2='';
    if utilities.is_set (str) then
    ws_url = table.concat ({ -- build a Wikisource URL
    wikisource_prefix, -- prefix
    str, -- article title
    });
    ws_label = str; -- label for the URL
    end
    elseif 1 == wl_type then -- simple wikilink: [[Wikisource:ws article]]
    str = D:match ('^[Ww]ikisource:(.+)') or D:match ('^[Ss]:(.+)'); -- article title from interwiki link with long-form or short-form namespace
    if utilities.is_set (str) then
    ws_url = table.concat ({ -- build a Wikisource URL
    wikisource_prefix, -- prefix
    str, -- article title
    });
    ws_label = str; -- label for the URL
    end
    elseif 2 == wl_type then -- non-so-simple wikilink: [[Wikisource:ws article|displayed text]] ([[L|D]])
    str = L:match ('^[Ww]ikisource:(.+)') or L:match ('^[Ss]:(.+)'); -- article title from interwiki link with long-form or short-form namespace
    if utilities.is_set (str) then
    ws_label = D; -- get ws article name from display portion of interwiki link
    ws_url = table.concat ({ -- build a Wikisource URL
    wikisource_prefix, -- prefix
    str, -- article title without namespace from link portion of wikilink
    });
    end
    end


    if date:match("^%d%d%d%d%-%d%d%-%d%d$") then
    if ws_url then
    date = substitute (cfg.presentation['nowrap1'], date);
    ws_url = mw.uri.encode (ws_url, 'WIKI'); -- make a usable URL
    ws_url = ws_url:gsub ('%%23', '#'); -- undo percent-encoding of fragment marker
    elseif date:match("^%a+%s*%d%d?,%s*%d%d%d%d$") or date:match ("^%d%d?%s*%a+%s*%d%d%d%d$") then
    cap, cap2 = string.match (date, "^(.*)%s+(%d%d%d%d)$");
    date = substitute (cfg.presentation['nowrap2'], {cap, cap2});
    end
    end
     
    return date;
    return ws_url, ws_label, L or D; -- return proper URL or nil and a label or nil
    end
    end


    --[[--------------------------< IS _ V A L I D _ I S X N >-----------------------------------------------------


    ISBN-10 and ISSN validator code calculates checksum across all isbn/issn digits including the check digit. ISBN-13 is checked in check_isbn().
    --[[----------------< F O R M A T _ P E R I O D I C A L >-----------------------
    If the number is valid the result will be 0. Before calling this function, issbn/issn must be checked for length and stripped of dashes,
     
    spaces and other non-isxn characters.
    Format the three periodical parameters: |script-<periodical>=, |<periodical>=,
    and |trans-<periodical>= into a single Periodical meta-parameter.


    ]]
    ]]


    local function is_valid_isxn (isxn_str, len)
    local function format_periodical (script_periodical, script_periodical_source, periodical, trans_periodical)
    local temp = 0;
    local periodical_error = '';
    isxn_str = { isxn_str:byte(1, len) }; -- make a table of byte values '0' → 0x30 .. '9'  → 0x39, 'X' → 0x58
     
    len = len+1; -- adjust to be a loop counter
    if not utilities.is_set (periodical) then
    for i, v in ipairs( isxn_str ) do -- loop through all of the bytes and calculate the checksum
    periodical = ''; -- to be safe for concatenation
    if v == string.byte( "X" ) then -- if checkdigit is X (compares the byte value of 'X' which is 0x58)
    else
    temp = temp + 10*( len - i ); -- it represents 10 decimal
    periodical = utilities.wrap_style ('italic-title', periodical); -- style
    else
    temp = temp + tonumber( string.char(v) )*(len-i);
    end
    end
    end
    return temp % 11 == 0; -- returns true if calculation result is zero
    end


    periodical = script_concatenate (periodical, script_periodical, script_periodical_source); -- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped


    --[[--------------------------< IS _ V A L I D _ I S X N  _ 1 3 >----------------------------------------------
    if utilities.is_set (trans_periodical) then
    trans_periodical = utilities.wrap_style ('trans-italic-title', trans_periodical);
    if utilities.is_set (periodical) then
    periodical = periodical .. ' ' .. trans_periodical;
    else -- here when trans-periodical without periodical or script-periodical
    periodical = trans_periodical;
    periodical_error = ' ' .. utilities.set_message ('err_trans_missing_title', {'periodical'});
    end
    end


    ISBN-13 and ISMN validator code calculates checksum across all 13 isbn/ismn digits including the check digit.
    return periodical .. periodical_error;
    If the number is valid, the result will be 0. Before calling this function, isbn-13/ismn must be checked for length
    end
    and stripped of dashes, spaces and other non-isxn-13 characters.


    ]]


    local function is_valid_isxn_13 (isxn_str)
    --[[------------------< F O R M A T _ C H A P T E R _ T I T L E >---------------
    local temp=0;
    isxn_str = { isxn_str:byte(1, 13) }; -- make a table of byte values '0' → 0x30 .. '9'  → 0x39
    for i, v in ipairs( isxn_str ) do
    temp = temp + (3 - 2*(i % 2)) * tonumber( string.char(v) ); -- multiply odd index digits by 1, even index digits by 3 and sum; includes check digit
    end
    return temp % 10 == 0; -- sum modulo 10 is zero when isbn-13/ismn is correct
    end


    --[[--------------------------< C H E C K _ I S B N >------------------------------------------------------------
    Format the four chapter parameters: |script-chapter=, |chapter=, |trans-chapter=,
    and |chapter-url= into a single chapter meta- parameter (chapter_url_source used
    for error messages).


    Determines whether an ISBN string is valid
    ]]


    ]]
    local function format_chapter_title (script_chapter, script_chapter_source, chapter, chapter_source, trans_chapter, trans_chapter_source, chapter_url, chapter_url_source, no_quotes, access)
    local chapter_error = '';


    local function check_isbn( isbn_str )
    local ws_url, ws_label, L = wikisource_url_make (chapter); -- make a wikisource URL and label from a wikisource interwiki link
    if nil ~= isbn_str:match("[^%s-0-9X]") then return false; end -- fail if isbn_str contains anything but digits, hyphens, or the uppercase X
    if ws_url then
    isbn_str = isbn_str:gsub( "-", "" ):gsub( " ", "" ); -- remove hyphens and spaces
    ws_label = ws_label:gsub ('_', ' '); -- replace underscore separators with space characters
    local len = isbn_str:len();
    chapter = ws_label;
    if len ~= 10 and len ~= 13 then
    return false;
    end
    end


    if len == 10 then
    if not utilities.is_set (chapter) then
    if isbn_str:match( "^%d*X?$" ) == nil then return false; end
    chapter = ''; -- to be safe for concatenation
    return is_valid_isxn(isbn_str, 10);
    else
    else
    local temp = 0;
    if false == no_quotes then
    if isbn_str:match( "^97[89]%d*$" ) == nil then return false; end -- isbn13 begins with 978 or 979; ismn begins with 979
    chapter = kern_quotes (chapter); -- if necessary, separate chapter title's leading and trailing quote marks from module provided quote marks
    return is_valid_isxn_13 (isbn_str);
    chapter = utilities.wrap_style ('quoted-title', chapter);
    end
    end
    end
    end


    --[[--------------------------< C H E C K _ I S M N >------------------------------------------------------------
    chapter = script_concatenate (chapter, script_chapter, script_chapter_source); -- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped


    Determines whether an ISMN string is valid. Similar to isbn-13, ismn is 13 digits begining 979-0-... and uses the
    if utilities.is_set (chapter_url) then
    same check digit calculations. See http://www.ismn-international.org/download/Web_ISMN_Users_Manual_2008-6.pdf
    chapter = external_link (chapter_url, chapter, chapter_url_source, access); -- adds bare_url_missing_title error if appropriate
    section 2, pages 9–12.
    elseif ws_url then
    chapter = external_link (ws_url, chapter .. '&nbsp;', 'ws link in chapter'); -- adds bare_url_missing_title error if appropriate; space char to move icon away from chap text; TODO: better way to do this?
    chapter = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, chapter});
    end


    ]]
    if utilities.is_set (trans_chapter) then
    trans_chapter = utilities.wrap_style ('trans-quoted-title', trans_chapter);
    if utilities.is_set (chapter) then
    chapter = chapter .. ' ' .. trans_chapter;
    else -- here when trans_chapter without chapter or script-chapter
    chapter = trans_chapter;
    chapter_source = trans_chapter_source:match ('trans%-?(.+)'); -- when no chapter, get matching name from trans-<param>
    chapter_error = ' ' .. utilities.set_message ('err_trans_missing_title', {chapter_source});
    end
    end


    local function ismn (id)
    return chapter .. chapter_error;
    local handler = cfg.id_handlers['ISMN'];
    end
    local text;
    local valid_ismn = true;


    id=id:gsub( "[%s-–]", "" ); -- strip spaces, hyphens, and endashes from the ismn


    if 13 ~= id:len() or id:match( "^9790%d*$" ) == nil then -- ismn must be 13 digits and begin 9790
    --[[----------------< H A S _ I N V I S I B L E _ C H A R S >-------------------
    valid_ismn = false;
    else
    valid_ismn=is_valid_isxn_13 (id); -- validate ismn
    end


    -- text = internal_link_id({link = handler.link, label = handler.label, -- use this (or external version) when there is some place to link to
    This function searches a parameter's value for non-printable or invisible characters.
    -- prefix=handler.prefix,id=id,separator=handler.separator, encode=handler.encode})
    The search stops at the first match.
    text="[[" .. handler.link .. "|" .. handler.label .. "]]" .. handler.separator .. id; -- because no place to link to yet


    if false == valid_ismn then
    This function will detect the visible replacement character when it is part of the Wikisource.
    text = text .. ' ' .. set_error( 'bad_ismn' ) -- add an error message if the issn is invalid
    end
    return text;
    end


    --[[--------------------------< I S S N >----------------------------------------------------------------------
    Detects but ignores nowiki and math stripmarkers.  Also detects other named stripmarkers
    (gallery, math, pre, ref) and identifies them with a slightly different error message.
    See also coins_cleanup().


    Validate and format an issn.  This code fixes the case where an editor has included an ISSN in the citation but has separated the two groups of four
    Output of this function is an error message that identifies the character or the
    digits with a space.  When that condition occurred, the resulting link looked like this:
    Unicode group, or the stripmarker that was detected along with its position (or,
     
    for multi-byte characters, the position of its first byte) in the parameter value.
    |issn=0819 4327 gives: [http://www.worldcat.org/issn/0819 4327 0819 4327]  -- can't have spaces in an external link
    This code now prevents that by inserting a hyphen at the issn midpoint.  It also validates the issn for length and makes sure that the checkdigit agrees
    with the calculated value.  Incorrect length (8 digits), characters other than 0-9 and X, or checkdigit / calculated value mismatch will all cause a check issn
    error message.  The issn is always displayed with a hyphen, even if the issn was given as a single group of 8 digits.


    ]]
    ]]


    local function issn(id)
    local function has_invisible_chars (param, v)
    local issn_copy = id; -- save a copy of unadulterated issn; use this version for display if issn does not validate
    local position = ''; -- position of invisible char or starting position of stripmarker
    local handler = cfg.id_handlers['ISSN'];
    local capture; -- used by stripmarker detection to hold name of the stripmarker
    local text;
    local stripmarker; -- boolean set true when a stripmarker is found
    local valid_issn = true;


    id=id:gsub( "[%s-–]", "" ); -- strip spaces, hyphens, and endashes from the issn
    capture = string.match (v, '[%w%p ]*'); -- test for values that are simple ASCII text and bypass other tests if true
     
    if capture == v then -- if same there are no Unicode characters
    if 8 ~= id:len() or nil == id:match( "^%d*X?$" ) then -- validate the issn: 8 digits long, containing only 0-9 or X in the last position
    return;
    valid_issn=false; -- wrong length or improper character
    else
    valid_issn=is_valid_isxn(id, 8); -- validate issn
    end
    end


    if true == valid_issn then
    for _, invisible_char in ipairs (cfg.invisible_chars) do
    id = string.sub( id, 1, 4 ) .. "-" .. string.sub( id, 5 ); -- if valid, display correctly formatted version
    local char_name = invisible_char[1]; -- the character or group name
    else
    local pattern = invisible_char[2]; -- the pattern used to find it
    id = issn_copy; -- if not valid, use the show the invalid issn with error message
    position, _, capture = mw.ustring.find (v, pattern); -- see if the parameter value contains characters that match the pattern
    end
    if position and (cfg.invisible_defs.zwj == capture) then -- if we found a zero-width joiner character
    text = external_link_id({link = handler.link, label = handler.label,
    if mw.ustring.find (v, cfg.indic_script) then -- it's ok if one of the Indic scripts
    prefix=handler.prefix,id=id,separator=handler.separator, encode=handler.encode})
    position = nil; -- unset position
    elseif cfg.emoji[mw.ustring.codepoint (v, position+1)] then -- is zwj followed by a character listed in emoji{}?
    if false == valid_issn then
    position = nil; -- unset position
    text = text .. ' ' .. set_error( 'bad_issn' ) -- add an error message if the issn is invalid
    end
    end  
    end
    return text
    if position then
    end
    if 'nowiki' == capture or 'math' == capture or -- nowiki and math stripmarkers (not an error condition)
     
    ('templatestyles' == capture and utilities.in_array (param, {'id', 'quote'})) then -- templatestyles stripmarker allowed in these parameters
    --[[--------------------------< A M A Z O N >------------------------------------------------------------------
    stripmarker = true; -- set a flag
     
    elseif true == stripmarker and cfg.invisible_defs.del == capture then -- because stripmakers begin and end with the delete char, assume that we've found one end of a stripmarker
    Formats a link to Amazon.  Do simple error checking: asin must be mix of 10 numeric or uppercase alpha
    position = nil; -- unset
    characters. If a mix, first character must be uppercase alpha; if all numeric, asins must be 10-digit
    else
    isbn. If 10-digit isbn, add a maintenance category so a bot or awb script can replace |asin= with |isbn=.
    local err_msg;
    Error message if not 10 characters, if not isbn10, if mixed and first character is a digit.
    if capture and not (cfg.invisible_defs.del == capture or cfg.invisible_defs.zwj == capture) then
     
    err_msg = capture .. ' ' .. char_name;
    ]]
    else
     
    err_msg = char_name .. ' ' .. 'character';
    local function amazon(id, domain)
    end
    local err_cat = ""


    if not id:match("^[%d%u][%d%u][%d%u][%d%u][%d%u][%d%u][%d%u][%d%u][%d%u][%d%u]$") then
    table.insert (z.message_tail, {utilities.set_message ('err_invisible_char', {err_msg, utilities.wrap_style ('parameter', param), position}, true)}); -- add error message
    err_cat =  ' ' .. set_error ('bad_asin'); -- asin is not a mix of 10 uppercase alpha and numeric characters
    return; -- and done with this parameter
    else
    if id:match("^%d%d%d%d%d%d%d%d%d[%dX]$") then -- if 10-digit numeric (or 9 digits with terminal X)
    if check_isbn( id ) then -- see if asin value is isbn10
    add_maint_cat ('ASIN');
    elseif not is_set (err_cat) then
    err_cat =  ' ' .. set_error ('bad_asin'); -- asin is not isbn10
    end
    end
    elseif not id:match("^%u[%d%u]+$") then
    err_cat =  ' ' .. set_error ('bad_asin'); -- asin doesn't begin with uppercase alpha
    end
    end
    end
    end
    if not is_set(domain) then
    domain = "com";
    elseif in_array (domain, {'jp', 'uk'}) then -- Japan, United Kingdom
    domain = "co." .. domain;
    elseif in_array (domain, {'au', 'br', 'mx'}) then -- Australia, Brazil, Mexico
    domain = "com." .. domain;
    end
    local handler = cfg.id_handlers['ASIN'];
    return external_link_id({link=handler.link,
    label=handler.label, prefix=handler.prefix .. domain .. "/dp/",
    id=id, encode=handler.encode, separator = handler.separator}) .. err_cat;
    end
    end


    --[[--------------------------< A R X I V >--------------------------------------------------------------------


    See: http://arxiv.org/help/arxiv_identifier
    --[[-------------------< A R G U M E N T _ W R A P P E R >----------------------


    format and error check arXiv identifier.  There are three valid forms of the identifier:
    Argument wrapper.  This function provides support for argument mapping defined
    the first form, valid only between date codes 9108 and 0703 is:
    in the configuration file so that multiple names can be transparently aliased to
    arXiv:<archive>.<class>/<date code><number><version>
    single internal variable.
    where:
    <archive> is a string of alpha characters - may be hyphenated; no other punctuation
    <class> is a string of alpha characters - may be hyphenated; no other punctuation
    <date code> is four digits in the form YYMM where YY is the last two digits of the four-digit year and MM is the month number January = 01
    first digit of YY for this form can only 9 and 0
    <number> is a three-digit number
    <version> is a 1 or more digit number preceded with a lowercase v; no spaces (undocumented)
    the second form, valid from April 2007 through December 2014 is:
    arXiv:<date code>.<number><version>
    where:
    <date code> is four digits in the form YYMM where YY is the last two digits of the four-digit year and MM is the month number January = 01
    <number> is a four-digit number
    <version> is a 1 or more digit number preceded with a lowercase v; no spaces


    the third form, valid from January 2015 is:
    arXiv:<date code>.<number><version>
    where:
    <date code> and <version> are as defined for 0704-1412
    <number> is a five-digit number
    ]]
    ]]


    local function arxiv (id, class)
    local function argument_wrapper ( args )
    local handler = cfg.id_handlers['ARXIV'];
    local origin = {};
    local year, month, version;
    local err_cat = '';
    local text;
    if id:match("^%a[%a%.%-]+/[90]%d[01]%d%d%d%d$") or id:match("^%a[%a%.%-]+/[90]%d[01]%d%d%d%dv%d+$") then -- test for the 9108-0703 format w/ & w/o version
    return setmetatable({
    year, month = id:match("^%a[%a%.%-]+/([90]%d)([01]%d)%d%d%d[v%d]*$");
    ORIGIN = function ( self, k )
    year = tonumber(year);
    local dummy = self[k]; -- force the variable to be loaded.
    month = tonumber(month);
    return origin[k];
    if ((not (90 < year or 8 > year)) or (1 > month or 12 < month)) or -- if invalid year or invalid month
    ((91 == year and 7 > month) or (7 == year and 3 < month)) then -- if years ok, are starting and ending months ok?
    err_cat = ' ' .. set_error( 'bad_arxiv' ); -- set error message
    end
    end
    elseif id:match("^%d%d[01]%d%.%d%d%d%d$") or id:match("^%d%d[01]%d%.%d%d%d%dv%d+$") then -- test for the 0704-1412 w/ & w/o version
    },
    year, month = id:match("^(%d%d)([01]%d)%.%d%d%d%d[v%d]*$");
    {
    year = tonumber(year);
    __index = function ( tbl, k )
    month = tonumber(month);
    if origin[k] ~= nil then
    if ((7 > year) or (14 < year) or (1 > month or 12 < month)) or -- is year invalid or is month invalid? (doesn't test for future years)
    return nil;
    ((7 == year) and (4 > month)) then --or -- when year is 07, is month invalid (before April)?
    end
    err_cat = ' ' .. set_error( 'bad_arxiv' ); -- set error message
    end
    local args, list, v = args, cfg.aliases[k];
    elseif id:match("^%d%d[01]%d%.%d%d%d%d%d$") or id:match("^%d%d[01]%d%.%d%d%d%d%dv%d+$") then -- test for the 1501- format w/ & w/o version
    year, month = id:match("^(%d%d)([01]%d)%.%d%d%d%d%d[v%d]*$");
    if type( list ) == 'table' then
    year = tonumber(year);
    v, origin[k] = utilities.select_one ( args, list, 'err_redundant_parameters' );
    month = tonumber(month);
    if origin[k] == nil then
    if ((15 > year) or (1 > month or 12 < month)) then -- is year invalid or is month invalid? (doesn't test for future years)
    origin[k] = ''; -- Empty string, not nil
    err_cat = ' ' .. set_error( 'bad_arxiv' ); -- set error message
    end
    end
    elseif list ~= nil then
    else
    v, origin[k] = args[list], list;
    err_cat = ' ' .. set_error( 'bad_arxiv' ); -- arXiv id doesn't match any format
    else
    end
    -- maybe let through instead of raising an error?
     
    -- v, origin[k] = args[k], k;
    text = external_link_id({link = handler.link, label = handler.label,
    error( cfg.messages['unknown_argument_map'] .. ': ' .. k);
    prefix=handler.prefix,id=id,separator=handler.separator, encode=handler.encode}) .. err_cat;
    end
     
    if is_set (class) then
    -- Empty strings, not nil;
    class = ' [[' .. '//arxiv.org/archive/' .. class .. ' ' .. class .. ']]'; -- external link within square brackets, not wikilink
    if v == nil then
    else
    v = '';
    class = ''; -- empty string for concatenation
    origin[k] = '';
    end
    end
    return text .. class;
    tbl = rawset( tbl, k, v );
    end
    return v;
     
    end,
    --[[
    });
    lccn normalization (http://www.loc.gov/marc/lccn-namespace.html#normalization)
    end
    1. Remove all blanks.
    2. If there is a forward slash (/) in the string, remove it, and remove all characters to the right of the forward slash.
    3. If there is a hyphen in the string:
    a. Remove it.
    b. Inspect the substring following (to the right of) the (removed) hyphen. Then (and assuming that steps 1 and 2 have been carried out):
    1. All these characters should be digits, and there should be six or less. (not done in this function)
    2. If the length of the substring is less than 6, left-fill the substring with zeroes until the length is six.
     
    Returns a normalized lccn for lccn() to validate.  There is no error checking (step 3.b.1) performed in this function.
    ]]
     
    local function normalize_lccn (lccn)
    lccn = lccn:gsub ("%s", ""); -- 1. strip whitespace


    if nil ~= string.find (lccn,'/') then
    lccn = lccn:match ("(.-)/"); -- 2. remove forward slash and all character to the right of it
    end


    local prefix
    --[[--------------------------< N O W R A P _ D A T E >-------------------------
    local suffix
     
    prefix, suffix = lccn:match ("(.+)%-(.+)"); -- 3.a remove hyphen by splitting the string into prefix and suffix
    When date is YYYY-MM-DD format wrap in nowrap span: <span ...>YYYY-MM-DD</span>.
    When date is DD MMMM YYYY or is MMMM DD, YYYY then wrap in nowrap span:
    <span ...>DD MMMM</span> YYYY or <span ...>MMMM DD,</span> YYYY
     
    DOES NOT yet support MMMM YYYY or any of the date ranges.
     
    ]]
     
    local function nowrap_date (date)
    local cap = '';
    local cap2 = '';


    if nil ~= suffix then -- if there was a hyphen
    if date:match("^%d%d%d%d%-%d%d%-%d%d$") then
    suffix=string.rep("0", 6-string.len (suffix)) .. suffix; -- 3.b.2 left fill the suffix with 0s if suffix length less than 6
    date = utilities.substitute (cfg.presentation['nowrap1'], date);
    lccn=prefix..suffix; -- reassemble the lccn
    elseif date:match("^%a+%s*%d%d?,%s+%d%d%d%d$") or date:match ("^%d%d?%s*%a+%s+%d%d%d%d$") then
    cap, cap2 = string.match (date, "^(.*)%s+(%d%d%d%d)$");
    date = utilities.substitute (cfg.presentation['nowrap2'], {cap, cap2});
    end
    end
    return lccn;
    return date;
    end
    end
     


    --[[
    --[[--------------------------< S E T _ T I T L E T Y P E >---------------------
    Format LCCN link and do simple error checking.  LCCN is a character string 8-12 characters long. The length of the LCCN dictates the character type of the first 1-3 characters; the
    rightmost eight are always digits. http://info-uri.info/registry/OAIHandler?verb=GetRecord&metadataPrefix=reg&identifier=info:lccn/


    length = 8 then all digits
    This function sets default title types (equivalent to the citation including
    length = 9 then lccn[1] is lower case alpha
    |type=<default value>) for those templates that have defaults. Also handles the
    length = 10 then lccn[1] and lccn[2] are both lower case alpha or both digits
    special case where it is desirable to omit the title type from the rendered citation
    length = 11 then lccn[1] is lower case alpha, lccn[2] and lccn[3] are both lower case alpha or both digits
    (|type=none).
    length = 12 then lccn[1] and lccn[2] are both lower case alpha


    ]]
    ]]


    local function lccn(lccn)
    local function set_titletype (cite_class, title_type)
    local handler = cfg.id_handlers['LCCN'];
    if utilities.is_set (title_type) then
    local err_cat = ''; -- presume that LCCN is valid
    if 'none' == cfg.keywords_xlate[title_type] then
    local id = lccn; -- local copy of the lccn
    title_type = ''; -- if |type=none then type parameter not displayed
    end
    return title_type; -- if |type= has been set to any other value use that value
    end
     
    return cfg.title_types [cite_class] or ''; -- set template's default title type; else empty string for concatenation
    end


    id = normalize_lccn (id); -- get canonical form (no whitespace, hyphens, forward slashes)
    local len = id:len(); -- get the length of the lccn


    if 8 == len then
    --[[--------------------------< H Y P H E N _ T O _ D A S H >--------------------------------------------------
    if id:match("[^%d]") then -- if LCCN has anything but digits (nil if only digits)
     
    err_cat = ' ' .. set_error( 'bad_lccn' ); -- set an error message
    Converts a hyphen to a dash under certain conditions. The hyphen must separate
    end
    like items; unlike items are returned unmodified. These forms are modified:
    elseif 9 == len then -- LCCN should be adddddddd
    letter - letter (A - B)
    if nil == id:match("%l%d%d%d%d%d%d%d%d") then -- does it match our pattern?
    digit - digit (4-5)
    err_cat = ' ' .. set_error( 'bad_lccn' ); -- set an error message
    digit separator digit - digit separator digit (4.1-4.5 or 4-1-4-5)
    end
    letterdigit - letterdigit (A1-A5) (an optional separator between letter and
    elseif 10 == len then -- LCCN should be aadddddddd or dddddddddd
    digit is supported – a.1-a.5 or a-1-a-5)
    if id:match("[^%d]") then -- if LCCN has anything but digits (nil if only digits) ...
    digitletter - digitletter (5a - 5d) (an optional separator between letter and
    if nil == id:match("^%l%l%d%d%d%d%d%d%d%d") then -- ... see if it matches our pattern
    digit is supported – 5.a-5.d or 5-a-5-d)
    err_cat = ' ' .. set_error( 'bad_lccn' ); -- no match, set an error message
    end
    end
    elseif 11 == len then -- LCCN should be aaadddddddd or adddddddddd
    if not (id:match("^%l%l%l%d%d%d%d%d%d%d%d") or id:match("^%l%d%d%d%d%d%d%d%d%d%d")) then -- see if it matches one of our patterns
    err_cat = ' ' .. set_error( 'bad_lccn' ); -- no match, set an error message
    end
    elseif 12 == len then -- LCCN should be aadddddddddd
    if not id:match("^%l%l%d%d%d%d%d%d%d%d%d%d") then -- see if it matches our pattern
    err_cat = ' ' .. set_error( 'bad_lccn' ); -- no match, set an error message
    end
    else
    err_cat = ' ' .. set_error( 'bad_lccn' ); -- wrong length, set an error message
    end


    if not is_set (err_cat) and nil ~= lccn:find ('%s') then
    any other forms are returned unmodified.
    err_cat = ' ' .. set_error( 'bad_lccn' ); -- lccn contains a space, set an error message
    end


    return external_link_id({link = handler.link, label = handler.label,
    str may be a comma- or semicolon-separated list
    prefix=handler.prefix,id=lccn,separator=handler.separator, encode=handler.encode}) .. err_cat;
    end


    --[[
    Format PMID and do simple error checking.  PMIDs are sequential numbers beginning at 1 and counting up.  This code checks the PMID to see that it
    contains only digits and is less than test_limit; the value in local variable test_limit will need to be updated periodically as more PMIDs are issued.
    ]]
    ]]


    local function pmid(id)
    local function hyphen_to_dash( str )
    local test_limit = 30000000; -- update this value as PMIDs approach
    if not utilities.is_set (str) then
    local handler = cfg.id_handlers['PMID'];
    return str;
    local err_cat =  ''; -- presume that PMID is valid
    if id:match("[^%d]") then -- if PMID has anything but digits
    err_cat = ' ' .. set_error( 'bad_pmid' ); -- set an error message
    else -- PMID is only digits
    local id_num = tonumber(id); -- convert id to a number for range testing
    if 1 > id_num or test_limit < id_num then -- if PMID is outside test limit boundaries
    err_cat = ' ' .. set_error( 'bad_pmid' ); -- set an error message
    end
    end
    end
    return external_link_id({link = handler.link, label = handler.label,
    prefix=handler.prefix,id=id,separator=handler.separator, encode=handler.encode}) .. err_cat;
    end


    --[[--------------------------< I S _ E M B A R G O E D >------------------------------------------------------
    local accept; -- Boolean


    Determines if a PMC identifier's online version is embargoed. Compares the date in |embargo= against today's date.  If embargo date is
    str = str:gsub ('&[nm]dash;', {['&ndash;'] = '–', ['&mdash;'] = '—'}); -- replace &mdash; and &ndash; entities with their characters; semicolon mucks up the text.split
    in the future, returns the content of |embargo=; otherwise, returns and empty string because the embargo has expired or because
    str = str:gsub ('&#45;', '-'); -- replace HTML numeric entity with hyphen character
    |embargo= was not set in this cite.


    ]]
    str = str:gsub ('&nbsp;', ' '); -- replace &nbsp; entity with generic keyboard space character
    local out = {};
    local list = mw.text.split (str, '%s*[,;]%s*'); -- split str at comma or semicolon separators if there are any


    local function is_embargoed (embargo)
    for _, item in ipairs (list) do -- for each item in the list
    if is_set (embargo) then
    item, accept = utilities.has_accept_as_written (item); -- remove accept-this-as-written markup when it wraps all of item
    local lang = mw.getContentLanguage();
    if not accept and mw.ustring.match (item, '^%w*[%.%-]?%w+%s*[%-–—]%s*%w*[%.%-]?%w+$') then -- if a hyphenated range or has endash or emdash separators
    local good1, embargo_date, good2, todays_date;
    if item:match ('^%a+[%.%-]?%d+%s*%-%s*%a+[%.%-]?%d+$') or -- letterdigit hyphen letterdigit (optional separator between letter and digit)
    good1, embargo_date = pcall( lang.formatDate, lang, 'U', embargo );
    item:match ('^%d+[%.%-]?%a+%s*%-%s*%d+[%.%-]?%a+$') or -- digitletter hyphen digitletter (optional separator between digit and letter)
    good2, todays_date = pcall( lang.formatDate, lang, 'U' );
    item:match ('^%d+[%.%-]%d+%s*%-%s*%d+[%.%-]%d+$') or -- digit separator digit hyphen digit separator digit
    item:match ('^%d+%s*%-%s*%d+$') or -- digit hyphen digit
    if good1 and good2 then -- if embargo date and today's date are good dates
    item:match ('^%a+%s*%-%s*%a+$') then -- letter hyphen letter
    if tonumber( embargo_date ) >= tonumber( todays_date ) then -- is embargo date is in the future?
    item = item:gsub ('(%w*[%.%-]?%w+)%s*%-%s*(%w*[%.%-]?%w+)', '%1–%2'); -- replace hyphen, remove extraneous space characters
    return embargo; -- still embargoed
    else
    else
    add_maint_cat ('embargo')
    item = mw.ustring.gsub (item, '%s*[–—]%s*', '–'); -- for endash or emdash separated ranges, replace em with en, remove extraneous whitespace
    return ''; -- unset because embargo has expired
    end
    end
    end
    end
    table.insert (out, item); -- add the (possibly modified) item to the output table
    end
    end
    return ''; -- |embargo= not set return empty string
    end


    --[[--------------------------< P M C >------------------------------------------------------------------------
    local temp_str = ''; -- concatenate the output table into a comma separated string
     
    temp_str, accept = utilities.has_accept_as_written (table.concat (out, ', ')); -- remove accept-this-as-written markup when it wraps all of concatenated out
    Format a PMC, do simple error checking, and check for embargoed articles.
    if accept then
     
    temp_str = utilities.has_accept_as_written (str); -- when global markup removed, return original str; do it this way to suppress boolean second return value
    The embargo parameter takes a date for a value. If the embargo date is in the future the PMC identifier will not
    return temp_str;
    be linked to the article.  If the embargo date is today or in the past, or if it is empty or omitted, then the
    else
    PMC identifier is linked to the article through the link at cfg.id_handlers['PMC'].prefix.
    return temp_str; -- else, return assembled temp_str
     
    PMC embargo date testing is done in function is_embargoed () which is called earlier because when the citation
    has |pmc=<value> but does not have a |url= then |title= is linked with the PMC link. Function is_embargoed ()
    returns the embargo date if the PMC article is still embargoed, otherwise it returns an empty string.
     
    PMCs are sequential numbers beginning at 1 and counting up.  This code checks the PMC to see that it contains only digits and is less
    than test_limit; the value in local variable test_limit will need to be updated periodically as more PMCs are issued.
     
    ]]
     
    local function pmc(id, embargo)
    local test_limit = 5000000; -- update this value as PMCs approach
    local handler = cfg.id_handlers['PMC'];
    local err_cat =  ''; -- presume that PMC is valid
    local text;
     
    if id:match("[^%d]") then -- if PMC has anything but digits
    err_cat = ' ' .. set_error( 'bad_pmc' ); -- set an error message
    else -- PMC is only digits
    local id_num = tonumber(id); -- convert id to a number for range testing
    if 1 > id_num or test_limit < id_num then -- if PMC is outside test limit boundaries
    err_cat = ' ' .. set_error( 'bad_pmc' ); -- set an error message
    end
    end
    end
    if is_set (embargo) then -- is PMC is still embargoed?
    text="[[" .. handler.link .. "|" .. handler.label .. "]]:" .. handler.separator .. id .. err_cat; -- still embargoed so no external link
    else
    text = external_link_id({link = handler.link, label = handler.label, -- no embargo date or embargo has expired, ok to link to article
    prefix=handler.prefix,id=id,separator=handler.separator, encode=handler.encode}) .. err_cat;
    end
    return text;
    end
    end


    -- Formats a DOI and checks for DOI errors.


    -- DOI names contain two parts: prefix and suffix separated by a forward slash.
    --[[--------------------------< S A F E _ J O I N >-----------------------------
    -- Prefix: directory indicator '10.' followed by a registrant code
    -- Suffix: character string of any length chosen by the registrant


    -- This function checks a DOI name for: prefix/suffix.  If the doi name contains spaces or endashes,
    Joins a sequence of strings together while checking for duplicate separation characters.
    -- or, if it ends with a period or a comma, this function will emit a bad_doi error message.


    -- DOI names are case-insensitive and can incorporate any printable Unicode characters so the test for spaces, endash,
    ]]
    -- and terminal punctuation may not be technically correct but it appears, that in practice these characters are rarely if ever used in doi names.


    local function doi(id, inactive)
    local function safe_join( tbl, duplicate_char )
    local cat = ""
    local f = {}; -- create a function table appropriate to type of 'duplicate character'
    local handler = cfg.id_handlers['DOI'];
    if 1 == #duplicate_char then -- for single byte ASCII characters use the string library functions
    f.gsub = string.gsub
    local text;
    f.match = string.match
    if is_set(inactive) then
    f.sub = string.sub
    local inactive_year = inactive:match("%d%d%d%d") or ''; -- try to get the year portion from the inactive date
    else -- for multi-byte characters use the ustring library functions
    text = "[[" .. handler.link .. "|" .. handler.label .. "]]:" .. id;
    f.gsub = mw.ustring.gsub
    if is_set(inactive_year) then
    f.match = mw.ustring.match
    table.insert( z.error_categories, "Pages with DOIs inactive since " .. inactive_year );
    f.sub = mw.ustring.sub
    else
    table.insert( z.error_categories, "Pages with inactive DOIs" ); -- when inactive doesn't contain a recognizable year
    end
    end
    inactive = " (" .. cfg.messages['inactive'] .. " " .. inactive .. ")"
    else
    text = external_link_id({link = handler.link, label = handler.label,
    prefix=handler.prefix,id=id,separator=handler.separator, encode=handler.encode})
    inactive = ""
    end


    if nil == id:match("^10%.[^%s–]-/[^%s–]-[^%.,]$") then -- doi must begin with '10.', must contain a fwd slash, must not contain spaces or endashes, and must not end with period or comma
    local str = ''; -- the output string
    cat = ' ' .. set_error( 'bad_doi' );
    local comp = ''; -- what does 'comp' mean?
    end
    local end_chr = '';
    return text .. inactive .. cat
    local trim;
    end
    for _, value in ipairs( tbl ) do
     
    if value == nil then value = ''; end
    -- Formats an OpenLibrary link, and checks for associated errors.
    local function openlibrary(id)
    if str == '' then -- if output string is empty
    local code = id:match("^%d+([AMW])$"); -- only digits followed by 'A', 'M', or 'W'
    str = value; -- assign value to it (first time through the loop)
    local handler = cfg.id_handlers['OL'];
    elseif value ~= '' then
    if value:sub(1, 1) == '<' then -- special case of values enclosed in spans and other markup.
    comp = value:gsub( "%b<>", "" ); -- remove HTML markup (<span>string</span> -> string)
    else
    comp = value;
    end
    -- typically duplicate_char is sepc
    if f.sub(comp, 1, 1) == duplicate_char then -- is first character same as duplicate_char? why test first character?
    --   Because individual string segments often (always?) begin with terminal punct for the
    --  preceding segment: 'First element' .. 'sepc next element' .. etc.?
    trim = false;
    end_chr = f.sub(str, -1, -1); -- get the last character of the output string
    -- str = str .. "<HERE(enchr=" .. end_chr .. ")" -- debug stuff?
    if end_chr == duplicate_char then -- if same as separator
    str = f.sub(str, 1, -2); -- remove it
    elseif end_chr == "'" then -- if it might be wiki-markup
    if f.sub(str, -3, -1) == duplicate_char .. "''" then -- if last three chars of str are sepc''
    str = f.sub(str, 1, -4) .. "''"; -- remove them and add back ''
    elseif  f.sub(str, -5, -1) == duplicate_char .. "]]''" then -- if last five chars of str are sepc]]''  
    trim = true; -- why? why do this and next differently from previous?
    elseif f.sub(str, -4, -1) == duplicate_char .. "]''" then -- if last four chars of str are sepc]''
    trim = true; -- same question
    end
    elseif end_chr == "]" then -- if it might be wiki-markup
    if f.sub(str, -3, -1) == duplicate_char .. "]]" then -- if last three chars of str are sepc]] wikilink
    trim = true;
    elseif f.sub(str, -3, -1) == duplicate_char .. '"]' then -- if last three chars of str are sepc"] quoted external link  
    trim = true;
    elseif  f.sub(str, -2, -1) == duplicate_char .. "]" then -- if last two chars of str are sepc] external link
    trim = true;
    elseif f.sub(str, -4, -1) == duplicate_char .. "'']" then -- normal case when |url=something & |title=Title.
    trim = true;
    end
    elseif end_chr == " " then -- if last char of output string is a space
    if f.sub(str, -2, -1) == duplicate_char .. " " then -- if last two chars of str are <sepc><space>
    str = f.sub(str, 1, -3); -- remove them both
    end
    end


    if ( code == "A" ) then
    if trim then
    return external_link_id({link=handler.link, label=handler.label,
    if value ~= comp then -- value does not equal comp when value contains HTML markup
    prefix=handler.prefix .. 'authors/OL',
    local dup2 = duplicate_char;
    id=id, separator=handler.separator, encode = handler.encode})
    if f.match(dup2, "%A" ) then dup2 = "%" .. dup2; end -- if duplicate_char not a letter then escape it
    elseif ( code == "M" ) then
    return external_link_id({link=handler.link, label=handler.label,
    value = f.gsub(value, "(%b<>)" .. dup2, "%1", 1 ) -- remove duplicate_char if it follows HTML markup
    prefix=handler.prefix .. 'books/OL',
    else
    id=id, separator=handler.separator, encode = handler.encode})
    value = f.sub(value, 2, -1 ); -- remove duplicate_char when it is first character
    elseif ( code == "W" ) then
    end
    return external_link_id({link=handler.link, label=handler.label,
    end
    prefix=handler.prefix .. 'works/OL',
    end
    id=id, separator=handler.separator, encode = handler.encode})
    str = str .. value; -- add it to the output string
    else
    end
    return external_link_id({link=handler.link, label=handler.label,
    end
    prefix=handler.prefix .. 'OL',
    return str;
    id=id, separator=handler.separator, encode = handler.encode}) .. ' ' .. set_error( 'bad_ol' );
    end
    end
    end




    --[[--------------------------< M E S S A G E _ I D >----------------------------------------------------------
    --[[--------------------------< I S _ S U F F I X >-----------------------------


    Validate and format a usenet message id.  Simple error checking, looks for 'id-left@id-right' not enclosed in
    returns true is suffix is properly formed Jr, Sr, or ordinal in the range 1–9.
    '<' and/or '>' angle brackets.
    Puncutation not allowed.


    ]]
    ]]


    local function message_id (id)
    local function is_suffix (suffix)
    local handler = cfg.id_handlers['USENETID'];
    if utilities.in_array (suffix, {'Jr', 'Sr', 'Jnr', 'Snr', '1st', '2nd', '3rd'}) or suffix:match ('^%dth$') then
     
    return true;
    text = external_link_id({link = handler.link, label = handler.label,
    end
    prefix=handler.prefix,id=id,separator=handler.separator, encode=handler.encode})
    return false;
    if not id:match('^.+@.+$') or not id:match('^[^<].*[^>]$')then -- doesn't have '@' or has one or first or last character is '< or '>'
    text = text .. ' ' .. set_error( 'bad_message_id' ) -- add an error message if the message id is invalid
    end  
    return text
    end
    end


    --[[--------------------------< S E T _ T I T L E T Y P E >----------------------------------------------------


    This function sets default title types (equivalent to the citation including |type=<default value>) for those templates that have defaults.
    --[[--------------------< I S _ G O O D _ V A N C _ N A M E >-------------------
    Also handles the special case where it is desirable to omit the title type from the rendered citation (|type=none).


    ]]
    For Vancouver style, author/editor names are supposed to be rendered in Latin
    (read ASCII) characters.  When a name uses characters that contain diacritical
    marks, those characters are to be converted to the corresponding Latin
    character. When a name is written using a non-Latin alphabet or logogram, that
    name is to be transliterated into Latin characters. The module doesn't do this
    so editors may/must.


    local function set_titletype (cite_class, title_type)
    This test allows |first= and |last= names to contain any of the letters defined
    if is_set(title_type) then
    in the four Unicode Latin character sets
    if "none" == title_type then
    [http://www.unicode.org/charts/PDF/U0000.pdf C0 Controls and Basic Latin] 0041–005A, 0061–007A
    title_type = ""; -- if |type=none then type parameter not displayed
    [http://www.unicode.org/charts/PDF/U0080.pdf C1 Controls and Latin-1 Supplement] 00C0–00D6, 00D8–00F6, 00F8–00FF
    end
    [http://www.unicode.org/charts/PDF/U0100.pdf Latin Extended-A] 0100–017F
    return title_type; -- if |type= has been set to any other value use that value
    [http://www.unicode.org/charts/PDF/U0180.pdf Latin Extended-B] 0180–01BF, 01C4–024F
    end


    return cfg.title_types [cite_class] or ''; -- set template's default title type; else empty string for concatenation
    |lastn= also allowed to contain hyphens, spaces, and apostrophes.
    end
    (http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35029/)
    |firstn= also allowed to contain hyphens, spaces, apostrophes, and periods


    --[[--------------------------< C L E A N _ I S B N >----------------------------------------------------------
    This original test:
    if nil == mw.ustring.find (last, "^[A-Za-zÀ-ÖØ-öø-ƿDŽ-ɏ%-%s%']*$")
    or nil == mw.ustring.find (first, "^[A-Za-zÀ-ÖØ-öø-ƿDŽ-ɏ%-%s%'%.]+[2-6%a]*$") then
    was written outside of the code editor and pasted here because the code editor
    gets confused between character insertion point and cursor position. The test has
    been rewritten to use decimal character escape sequence for the individual bytes
    of the Unicode characters so that it is not necessary to use an external editor
    to maintain this code.


    Removes irrelevant text and dashes from ISBN number
    \195\128-\195\150 – À-Ö (U+00C0–U+00D6 – C0 controls)
    Similar to that used for Special:BookSources
    \195\152-\195\182 – Ø-ö (U+00D8-U+00F6 – C0 controls)
    \195\184-\198\191 – ø-ƿ (U+00F8-U+01BF – C0 controls, Latin extended A & B)
    \199\132-\201\143 – DŽ-ɏ (U+01C4-U+024F – Latin extended B)


    ]]
    ]]


    local function clean_isbn( isbn_str )
    local function is_good_vanc_name (last, first, suffix, position)
    return isbn_str:gsub( "[^-0-9X]", "" );
    if not suffix then
    end
    if first:find ('[,%s]') then -- when there is a space or comma, might be first name/initials + generational suffix
    first = first:match ('(.-)[,%s]+'); -- get name/initials
    suffix = first:match ('[,%s]+(.+)$'); -- get generational suffix
    end
    end
    if utilities.is_set (suffix) then
    if not is_suffix (suffix) then
    add_vanc_error (cfg.err_msg_supl.suffix, position);
    return false; -- not a name with an appropriate suffix
    end
    end
    if nil == mw.ustring.find (last, "^[A-Za-z\195\128-\195\150\195\152-\195\182\195\184-\198\191\199\132-\201\143%-%s%']*$") or
    nil == mw.ustring.find (first, "^[A-Za-z\195\128-\195\150\195\152-\195\182\195\184-\198\191\199\132-\201\143%-%s%'%.]*$") then
    add_vanc_error (cfg.err_msg_supl['non-Latin char'], position);
    return false; -- not a string of Latin characters; Vancouver requires Romanization
    end;
    return true;
    end
     
     
    --[[--------------------------< R E D U C E _ T O _ I N I T I A L S >------------------------------------------


    --[[--------------------------< E S C A P E _ L U A _ M A G I C _ C H A R S >----------------------------------
    Attempts to convert names to initials in support of |name-list-style=vanc. 


    Returns a string where all of lua's magic characters have been escaped. This is important because functions like
    Names in |firstn= may be separated by spaces or hyphens, or for initials, a period.
    string.gsub() treat their pattern and replace strings as patterns, not literal strings.
    See http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35062/.
    ]]
    local function escape_lua_magic_chars (argument)
    argument = argument:gsub("%%", "%%%%"); -- replace % with %%
    argument = argument:gsub("([%^%$%(%)%.%[%]%*%+%-%?])", "%%%1"); -- replace all other lua magic pattern characters
    return argument;
    end


    --[[--------------------------< S T R I P _ A P O S T R O P H E _ M A R K U P >--------------------------------
    Vancouver style requires family rank designations (Jr, II, III, etc.) to be rendered
    as Jr, 2nd, 3rd, etc.  See http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35085/.
    This code only accepts and understands generational suffix in the Vancouver format
    because Roman numerals look like, and can be mistaken for, initials.


    Strip wiki italic and bold markup from argument so that it doesn't contaminate COinS metadata.
    This function uses ustring functions because firstname initials may be any of the
    This function strips common patterns of apostrophe markup.  We presume that editors who have taken the time to
    Unicode Latin characters accepted by is_good_vanc_name ().
    markup a title have, as a result, provided valid markup. When they don't, some single apostrophes are left behind.


    ]]
    ]]


    local function strip_apostrophe_markup (argument)
    local function reduce_to_initials(first, position)
    if not is_set (argument) then return argument; end
    local name, suffix = mw.ustring.match(first, "^(%u+) ([%dJS][%drndth]+)$");


    while true do
    if not name then -- if not initials and a suffix
    if argument:match ("%'%'%'%'%'") then -- bold italic (5)
    name = mw.ustring.match(first, "^(%u+)$"); -- is it just initials?
    argument=argument:gsub("%'%'%'%'%'", ""); -- remove all instances of it
    elseif argument:match ("%'%'%'%'") then -- italic start and end without content (4)
    argument=argument:gsub("%'%'%'%'", "");
    elseif argument:match ("%'%'%'") then -- bold (3)
    argument=argument:gsub("%'%'%'", "");
    elseif argument:match ("%'%'") then -- italic (2)
    argument=argument:gsub("%'%'", "");
    else
    break;
    end
    end
    end
    return argument; -- done
    end


    --[[--------------------------< M A K E _ C O I N S _ T I T L E >----------------------------------------------
    if name then -- if first is initials with or without suffix
    if 3 > mw.ustring.len (name) then -- if one or two initials
    if suffix then -- if there is a suffix
    if is_suffix (suffix) then -- is it legitimate?
    return first; -- one or two initials and a valid suffix so nothing to do
    else
    add_vanc_error (cfg.err_msg_supl.suffix, position); -- one or two initials with invalid suffix so error message
    return first; -- and return first unmolested
    end
    else
    return first; -- one or two initials without suffix; nothing to do
    end
    end
    end -- if here then name has 3 or more uppercase letters so treat them as a word


    Makes a title for COinS from Title and / or ScriptTitle (or any other name-script pairs)
    local initials, names = {}, {}; -- tables to hold name parts and initials
    local i = 1; -- counter for number of initials


    Apostrophe markup (bold, italics) is stripped from each value so that the COinS metadata isn't correupted with strings
    names = mw.text.split (first, '[%s,]+'); -- split into a table of names and possible suffix
    of %27%27...
    ]]


    local function make_coins_title (title, script)
    while names[i] do -- loop through the table
    if is_set (title) then
    if 1 < i and names[i]:match ('[%dJS][%drndth]+%.?$') then -- if not the first name, and looks like a suffix (may have trailing dot)
    title = strip_apostrophe_markup (title); -- strip any apostrophe markup
    names[i] = names[i]:gsub ('%.', ''); -- remove terminal dot if present
    else
    if is_suffix (names[i]) then -- if a legitimate suffix
    title=''; -- if not set, make sure title is an empty string
    table.insert (initials, ' ' .. names[i]); -- add a separator space, insert at end of initials table
    break; -- and done because suffix must fall at the end of a name
    end -- no error message if not a suffix; possibly because of Romanization
    end
    if 3 > i then
    table.insert (initials, mw.ustring.sub(names[i], 1, 1)); -- insert the initial at end of initials table
    end
    i = i + 1; -- bump the counter
    end
    end
    if is_set (script) then
    script = script:gsub ('^%l%l%s*:%s*', ''); -- remove language prefix if present (script value may now be empty string)
    return table.concat(initials) -- Vancouver format does not include spaces.
    script = strip_apostrophe_markup (script); -- strip any apostrophe markup
    else
    script=''; -- if not set, make sure script is an empty string
    end
    if is_set (title) and is_set (script) then
    script = ' ' .. script; -- add a space before we concatenate
    end
    return title .. script; -- return the concatenation
    end
    end


    --[[--------------------------< G E T _ C O I N S _ P A G E S >------------------------------------------------


    Extract page numbers from external wikilinks in any of the |page=, |pages=, or |at= parameters for use in COinS.
    --[[--------------------------< L I S T _ P E O P L E >--------------------------


    ]]
    Formats a list of people (authors, contributors, editors, interviewers, translators)


    local function get_coins_pages (pages)
    names in the list will be linked when
    local pattern;
    |<name>-link= has a value
    if not is_set (pages) then return pages; end -- if no page numbers then we're done
    |<name>-mask- does NOT have a value; masked names are presumed to have been
    rendered previously so should have been linked there
    while true do
    pattern = pages:match("%[(%w*:?//[^ ]+%s+)[%w%d].*%]"); -- pattern is the opening bracket, the url and following space(s): "[url "
    if nil == pattern then break; end -- no more urls
    pattern = escape_lua_magic_chars (pattern); -- pattern is not a literal string; escape lua's magic pattern characters
    pages = pages:gsub(pattern, ""); -- remove as many instances of pattern as possible
    end
    pages = pages:gsub("[%[%]]", ""); -- remove the brackets
    pages = pages:gsub("–", "-" ); -- replace endashes with hyphens
    pages = pages:gsub("&%w+;", "-" ); -- and replace html entities (&ndash; etc.) with hyphens; do we need to replace numerical entities like &#32; and the like?
    return pages;
    end


    -- Gets the display text for a wikilink like [[A|B]] or [[B]] gives B
    when |<name>-mask=0, the associated name is not rendered
    local function remove_wiki_link( str )
    return (str:gsub( "%[%[([^%[%]]*)%]%]", function(l)
    return l:gsub( "^[^|]*|(.*)$", "%1" ):gsub("^%s*(.-)%s*$", "%1");
    end));
    end


    -- Converts a hyphen to a dash
    ]]
    local function hyphen_to_dash( str )
    if not is_set(str) or str:match( "[%[%]{}<>]" ) ~= nil then
    return str;
    end
    return str:gsub( '-', '–' );
    end


    --[[--------------------------< S A F E _ J O I N >------------------------------------------------------------
    local function list_people (control, people, etal)
    local sep;
    local namesep;
    local format = control.format;
    local maximum = control.maximum;
    local name_list = {};


    Joins a sequence of strings together while checking for duplicate separation characters.
    if 'vanc' == format then -- Vancouver-like name styling?
     
    sep = cfg.presentation['sep_nl_vanc']; -- name-list separator between names is a comma
    ]]
    namesep = cfg.presentation['sep_name_vanc']; -- last/first separator is a space
     
    else
    local function safe_join( tbl, duplicate_char )
    sep = cfg.presentation['sep_nl']; -- name-list separator between names is a semicolon
    --[[
    namesep = cfg.presentation['sep_name']; -- last/first separator is <comma><space>
    Note: we use string functions here, rather than ustring functions.
    end
    This has considerably faster performance and should work correctly as
    if sep:sub (-1, -1) ~= " " then sep = sep .. " " end
    long as the duplicate_char is strict ASCII. The strings
    if utilities.is_set (maximum) and maximum < 1 then return "", 0; end -- returned 0 is for EditorCount; not used for other names
    in tbl may be ASCII or UTF8.
    ]]
    local str = ''; -- the output string
    for i, person in ipairs (people) do
    local comp = ''; -- what does 'comp' mean?
    if utilities.is_set (person.last) then
    local end_chr = '';
    local mask = person.mask;
    local trim;
    local one;
    for _, value in ipairs( tbl ) do
    local sep_one = sep;
    if value == nil then value = ''; end
     
    if utilities.is_set (maximum) and i > maximum then
    if str == '' then -- if output string is empty
    etal = true;
    str = value; -- assign value to it (first time through the loop)
    break;
    elseif value ~= '' then
    end
    if value:sub(1,1) == '<' then -- Special case of values enclosed in spans and other markup.
    comp = value:gsub( "%b<>", "" ); -- remove html markup (<span>string</span> -> string)
    if mask then
    local n = tonumber (mask); -- convert to a number if it can be converted; nil else
    if n then
    one = 0 ~= n and string.rep("&mdash;", n) or nil; -- make a string of (n > 0) mdashes, nil else, to replace name
    person.link = nil; -- don't create link to name if name is replaces with mdash string or has been set nil
    else
    one = mask; -- replace name with mask text (must include name-list separator)
    sep_one = " "; -- modify name-list separator
    end
    else
    else
    comp = value;
    one = person.last; -- get surname
    end
    local first = person.first -- get given name
    -- typically duplicate_char is sepc
    if utilities.is_set (first) then
    if comp:sub(1,1) == duplicate_char then -- is first charactier same as duplicate_char? why test first character?
    if ("vanc" == format) then -- if Vancouver format
    --  Because individual string segments often (always?) begin with terminal punct for th
    one = one:gsub ('%.', ''); -- remove periods from surnames (http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35029/)
    --  preceding segment: 'First element' .. 'sepc next element' .. etc?
    if not person.corporate and is_good_vanc_name (one, first, nil, i) then -- and name is all Latin characters; corporate authors not tested
    trim = false;
    first = reduce_to_initials (first, i); -- attempt to convert first name(s) to initials
    end_chr = str:sub(-1,-1); -- get the last character of the output string
    end
    -- str = str .. "<HERE(enchr=" .. end_chr.. ")" -- debug stuff?
    if end_chr == duplicate_char then -- if same as separator
    str = str:sub(1,-2); -- remove it
    elseif end_chr == "'" then -- if it might be wikimarkup
    if str:sub(-3,-1) == duplicate_char .. "''" then -- if last three chars of str are sepc''
    str = str:sub(1, -4) .. "''"; -- remove them and add back ''
    elseif str:sub(-5,-1) == duplicate_char .. "]]''" then -- if last five chars of str are sepc]]''
    trim = true; -- why? why do this and next differently from previous?
    elseif str:sub(-4,-1) == duplicate_char .. "]''" then -- if last four chars of str are sepc]''
    trim = true; -- same question
    end
    elseif end_chr == "]" then -- if it might be wikimarkup
    if str:sub(-3,-1) == duplicate_char .. "]]" then -- if last three chars of str are sepc]] wikilink
    trim = true;
    elseif str:sub(-2,-1) == duplicate_char .. "]" then -- if last two chars of str are sepc] external link
    trim = true;
    elseif str:sub(-4,-1) == duplicate_char .. "'']" then -- normal case when |url=something & |title=Title.
    trim = true;
    end
    elseif end_chr == " " then -- if last char of output string is a space
    if str:sub(-2,-1) == duplicate_char .. " " then -- if last two chars of str are <sepc><space>
    str = str:sub(1,-3); -- remove them both
    end
    end
    one = one .. namesep .. first;
    end
    end
     
    end
    if trim then
    if utilities.is_set (person.link) then
    if value ~= comp then -- value does not equal comp when value contains html markup
    one = utilities.make_wikilink (person.link, one); -- link author/editor
    local dup2 = duplicate_char;
    end
    if dup2:match( "%A" ) then dup2 = "%" .. dup2; end -- if duplicate_char not a letter then escape it
    if one then -- if <one> has a value (name, mdash replacement, or mask text replacement)
    table.insert (name_list, one); -- add it to the list of names
    value = value:gsub( "(%b<>)" .. dup2, "%1", 1 ) -- remove duplicate_char if it follows html markup
    table.insert (name_list, sep_one); -- add the proper name-list separator
    else
    end
    value = value:sub( 2, -1 ); -- remove duplicate_char when it is first character
    end
    end
    end
     
    local count = #name_list / 2; -- (number of names + number of separators) divided by 2
    if 0 < count then
    if 1 < count and not etal then
    if 'amp' == format then
    name_list[#name_list-2] = " & "; -- replace last separator with ampersand text
    elseif 'and' == format then
    if 2 == count then
    name_list[#name_list-2] = cfg.presentation.sep_nl_and; -- replace last separator with 'and' text
    else
    name_list[#name_list-2] = cfg.presentation.sep_nl_end; -- replace last separator with '(sep) and' text
    end
    end
    end
    end
    str = str .. value; --add it to the output string
    end
    end
    name_list[#name_list] = nil; -- erase the last separator
    end
    end
    return str;
    end 


    --[[--------------------------< I S _ G O O D _ V A N C _ N A M E >--------------------------------------------
    local result = table.concat (name_list); -- construct list
    if etal and utilities.is_set (result) then -- etal may be set by |display-authors=etal but we might not have a last-first list
    result = result .. sep .. ' ' .. cfg.messages['et al']; -- we've got a last-first list and etal so add et al.
    end
    return result, count; -- return name-list string and count of number of names (count used for editor names only)
    end


    For Vancouver Style, author/editor names are supposed to be rendered in Latin (read ASCII) characters.  When a name
    --[[--------------------< M A K E _ C I T E R E F _ I D >-----------------------
    uses characters that contain diacritical marks, those characters are to converted to the corresponding Latin character.
    When a name is written using a non-Latin alphabet or logogram, that name is to be transliterated into Latin characters.
    These things are not currently possible in this module so are left to the editor to do.


    This test allows |first= and |last= names to contain any of the letters defined in the four Unicode Latin character sets
    Generates a CITEREF anchor ID if we have at least one name or a date. Otherwise
    [http://www.unicode.org/charts/PDF/U0000.pdf C0 Controls and Basic Latin] 0041–005A, 0061–007A
    returns an empty string.
    [http://www.unicode.org/charts/PDF/U0080.pdf C1 Controls and Latin-1 Supplement] 00C0–00D6, 00D8–00F6, 00F8–00FF
    [http://www.unicode.org/charts/PDF/U0100.pdf Latin Extended-A] 0100–017F
    [http://www.unicode.org/charts/PDF/U0180.pdf Latin Extended-B] 0180–01BF, 01C4–024F
     
    |lastn= also allowed to contain hyphens, spaces, and apostrophes. (http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35029/)
    |firstn= also allowed to contain hyphens, spaces, apostrophes, and periods


    At the time of this writing, I had to write the 'if nil == mw.ustring.find ...' test ouside of the code editor and paste it here
    namelist is one of the contributor-, author-, or editor-name lists chosen in that
    because the code editor gets confused between character insertion point and cursor position.
    order.  year is Year or anchor_year.


    ]]
    ]]


    local function is_good_vanc_name (last, first)
    local function make_citeref_id (namelist, year)
    if nil == mw.ustring.find (last, "^[A-Za-zÀ-ÖØ-öø-ƿDŽ-ɏ%-%s%']*$") or nil == mw.ustring.find (first, "^[A-Za-zÀ-ÖØ-öø-ƿDŽ-ɏ%-%s%'%.]*$") then
    local names={}; -- a table for the one to four names and year
    add_vanc_error ();
    for i,v in ipairs (namelist) do -- loop through the list and take up to the first four last names
    return false; -- not a string of latin characters; Vancouver required Romanization
    names[i] = v.last
    end;
    if i == 4 then break end -- if four then done
    return true;
    end
    table.insert (names, year); -- add the year at the end
    local id = table.concat(names); -- concatenate names and year for CITEREF id
    if utilities.is_set (id) then -- if concatenation is not an empty string
    return "CITEREF" .. id; -- add the CITEREF portion
    else
    return ''; -- return an empty string; no reason to include CITEREF id in this citation
    end
    end
    end


    --[[--------------------------< R E D U C E _ T O _ I N I T I A L S >------------------------------------------
    Attempts to convert names to initials in support of |name-list-format=vanc. 


    Names in |firstn= may be separated by spaces or hyphens, or for initials, a period. See http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35062/.
    --[[---------------------< N A M E _ H A S _ E T A L >--------------------------


    Vancouver style requires family rank designations (Jr, II, III, etc) to be rendered as Jr, 2nd, 3rd, etc.  This form is not
    Evaluates the content of name parameters (author, editor, etc.) for variations on
    currently supported by this code so correctly formed names like Smith JL 2nd are converted to Smith J2. See http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35085/.
    the theme of et al.  If found, the et al. is removed, a flag is set to true and
    the function returns the modified name and the flag.


    This function uses ustring functions because firstname initials may be any of the unicode Latin characters accepted by is_good_vanc_name ().
    This function never sets the flag to false but returns its previous state because
    it may have been set by previous passes through this function or by the associated
    |display-<names>=etal parameter


    ]]
    ]]


    local function reduce_to_initials(first)
    local function name_has_etal (name, etal, nocat, param)
    if mw.ustring.match(first, "^%u%u$") then return first end; -- when first contains just two upper-case letters, nothing to do
    local initials = {}
    local i = 0; -- counter for number of initials
    for word in mw.ustring.gmatch(first, "[^%s%.%-]+") do -- names separated by spaces, hyphens, or periods
    table.insert(initials, mw.ustring.sub(word,1,1)) -- Vancouver format does not include full stops.
    i = i + 1; -- bump the counter
    if 2 <= i then break; end -- only two initials allowed in Vancouver system; if 2, quit
    end
    return table.concat(initials) -- Vancouver format does not include spaces.
    end


    --[[--------------------------< L I S T  _ P E O P L E >-------------------------------------------------------
    if utilities.is_set (name) then -- name can be nil in which case just return
     
    local patterns = cfg.et_al_patterns; -- get patterns from configuration
    Formats a list of people (e.g. authors / editors)
     
    for _, pattern in ipairs (patterns) do -- loop through all of the patterns
    ]]
    if name:match (pattern) then -- if this 'et al' pattern is found in name
     
    name = name:gsub (pattern, ''); -- remove the offending text
    local function list_people(control, people, etal)
    etal = true; -- set flag (may have been set previously here or by |display-<names>=etal)
    local sep;
    if not nocat then -- no categorization for |vauthors=
    local namesep;
    table.insert( z.message_tail, {utilities.set_message ('err_etal', {param})}); -- and set an error if not added
    local format = control.format
    local maximum = control.maximum
    local lastauthoramp = control.lastauthoramp;
    local text = {}
     
    if 'vanc' == format then -- Vancouver-like author/editor name styling?
    sep = ','; -- name-list separator between authors is a comma
    namesep = ' '; -- last/first separator is a space
    else
    sep = ';' -- name-list separator between authors is a semicolon
    namesep = ', ' -- last/first separator is <comma><space>
    end
    if sep:sub(-1,-1) ~= " " then sep = sep .. " " end
    if is_set (maximum) and maximum < 1 then return "", 0; end -- returned 0 is for EditorCount; not used for authors
    for i,person in ipairs(people) do
    if is_set(person.last) then
    local mask = person.mask
    local one
    local sep_one = sep;
    if is_set (maximum) and i > maximum then
    etal = true;
    break;
    elseif (mask ~= nil) then
    local n = tonumber(mask)
    if (n ~= nil) then
    one = string.rep("&mdash;",n)
    else
    one = mask;
    sep_one = " ";
    end
    else
    one = person.last
    local first = person.first
    if is_set(first) then
    if ( "vanc" == format ) then -- if vancouver format
    one = one:gsub ('%.', ''); -- remove periods from surnames (http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35029/)
    if not person.corporate and is_good_vanc_name (one, first) then -- and name is all Latin characters; corporate authors not tested
    first = reduce_to_initials(first) -- attempt to convert first name(s) to initials
    end
    end
    one = one .. namesep .. first
    end
    if is_set(person.link) and person.link ~= control.page_name then
    one = "[[" .. person.link .. "|" .. one .. "]]" -- link author/editor if this page is not the author's/editor's page
    end
    end
    if is_set(person.link) and ((nil ~= person.link:find("//")) or (nil ~= person.link:find("[%[%]]"))) then
    one = one .. " " .. set_error( 'bad_authorlink' ) end -- url or wikilink in author link;
    end
    end
    table.insert( text, one )
    table.insert( text, sep_one )
    end
    end
    end
    end


    local count = #text / 2; -- (number of names + number of separators) divided by 2
    return name, etal;
    if count > 0 then
    if count > 1 and is_set(lastauthoramp) and not etal then
    text[#text-2] = " & "; -- replace last separator with ampersand text
    end
    text[#text] = nil; -- erase the last separator
    end
    local result = table.concat(text) -- construct list
    if etal and is_set (result) then -- etal may be set by |display-authors=etal but we might not have a last-first list
    result = result .. sep .. ' ' .. cfg.messages['et al']; -- we've go a last-first list and etal so add et al.
    end
    return result, count
    end
    end


    --[[--------------------------< A N C H O R _ I D >------------------------------------------------------------


    Generates a CITEREF anchor ID if we have at least one name or a date.  Otherwise returns an empty string.
    --[[---------------------< N A M E _ I S _ N U M E R I C >----------------------


    ]]
    Add maint cat when name parameter value does not contain letters.  Does not catch
    mixed alphanumeric names so |last=A. Green (1922-1987) does not get caught in the
    current version of this test but |first=(1888) is caught.


    local function anchor_id( options )
    returns nothing
    local id = table.concat( options ); -- concatenate names and year for CITEREF id
     
    if is_set (id) then -- if concatenation is not an empty string
    ]]
    return "CITEREF" .. id; -- add the CITEREF portion
     
    else
    local function name_is_numeric (name, list_name)
    return ''; -- return an empty string; no reason to include CITEREF id in this citation
    if utilities.is_set (name) then
    if mw.ustring.match (name, '^[%A]+$') then -- when name does not contain any letters
    utilities.set_message ('maint_numeric_names', cfg.special_case_translation [list_name]); -- add a maint cat for this template
    end
    end
    end
    end
    end


    --[[--------------------------< N A M E _ H A S _ E T A L >----------------------------------------------------


    Evaluates the content of author and editor name parameters for variations on the theme of et al.  If found,
    --[[-------------------< N A M E _ H A S _ E D _ M A R K U P >------------------
    the et al. is removed, a flag is set to true and the function returns the modified name and the flag.
     
    Evaluates the content of author and editor parameters for extraneous editor annotations:
    ed, ed., eds, (Ed.), etc. These annotations do not belong in author parameters and
    are redundant in editor parameters.  If found, the function adds the editor markup
    maintenance category.


    This function never sets the flag to false but returns it's previous state because it may have been set by
    returns nothing
    previous passes through this function or by the parameters |display-authors=etal or |display-editors=etal


    ]]
    ]]


    local function name_has_etal (name, etal, nocat)
    local function name_has_ed_markup (name, list_name)
    local patterns = cfg.editor_markup_patterns; -- get patterns from configuration


    if is_set (name) then -- name can be nil in which case just return
    if utilities.is_set (name) then
    local etal_pattern = "[;,]? *[\"']*%f[Ee][Ee][Tt] *[Aa][Ll][%.\"']*$" -- variations on the 'et al' theme
    for _, pattern in ipairs (patterns) do -- spin through patterns table and
    local others_pattern = "[;,]? *%f[%a]and [Oo]thers"; -- and alternate to et al.
    if name:match (pattern) then
    utilities.set_message ('maint_extra_text_names', cfg.special_case_translation [list_name]); -- add a maint cat for this template
    if name:match (etal_pattern) then -- variants on et al.
    break;
    name = name:gsub (etal_pattern, ''); -- if found, remove
    etal = true; -- set flag (may have been set previously here or by |display-authors=etal)
    if not nocat then -- no categorization for |vauthors=
    add_maint_cat ('etal'); -- and add a category if not already added
    end
    elseif name:match (others_pattern) then -- if not 'et al.', then 'and others'?
    name = name:gsub (others_pattern, ''); -- if found, remove
    etal = true; -- set flag (may have been set previously here or by |display-authors=etal)
    if not nocat then -- no categorization for |vauthors=
    add_maint_cat ('etal'); -- and add a category if not already added
    end
    end
    end
    end
    end
    end
    return name, etal; --
    end
    end


    --[[--------------------------< E X T R A C T _ N A M E S >----------------------------------------------------
    Gets name list from the input arguments


    Searches through args in sequential order to find |lastn= and |firstn= parameters (or their aliases), and their matching link and mask parameters.
    --[[-----------------< N A M E _ H A S _ M U L T _ N A M E S >------------------
    Stops searching when both |lastn= and |firstn= are not found in args after two sequential attempts: found |last1=, |last2=, and |last3= but doesn't
    find |last4= and |last5= then the search is done.


    This function emits an error message when there is a |firstn= without a matching |lastn=.  When there are 'holes' in the list of last names, |last1= and |last3=
    Evaluates the content of last/surname (authors etc.) parameters for multiple names.
    are present but |last2= is missing, an error message is emitted. |lastn= is not required to have a matching |firstn=.
    Multiple names are indicated if there is more than one comma or any "unescaped"
    semicolons. Escaped semicolons are ones used as part of selected HTML entities.
    If the condition is met, the function adds the multiple name maintenance category.


    When an author or editor parameter contains some form of 'et al.', the 'et al.' is stripped from the parameter and a flag (etal) returned
    returns nothing
    that will cause list_people() to add the static 'et al.' text from Module:Citation/CS1/Configuration.  This keeps 'et al.' out of the
    template's metadata.  When this occurs, the page is added to a maintenance category.


    ]]
    ]]


    local function extract_names(args, list_name)
    local function name_has_mult_names (name, list_name)
    local names = {}; -- table of names
    local _, commas, semicolons, nbsps;
    local last; -- individual name components
    if utilities.is_set (name) then
    local first;
    _, commas = name:gsub (',', ''); -- count the number of commas
    local link;
    _, semicolons = name:gsub (';', ''); -- count the number of semicolons
    local mask;
    -- nbsps probably should be its own separate count rather than merged in
    local i = 1; -- loop counter/indexer
    -- some way with semicolons because Lua patterns do not support the
    local n = 1; -- output table indexer
    -- grouping operator that regex does, which means there is no way to add
    local count = 0; -- used to count the number of times we haven't found a |last= (or alias for authors, |editor-last or alias for editors)
    -- more entities to escape except by adding more counts with the new
    local etal=false; -- return value set to true when we find some form of et al. in an author parameter
    -- entities
    _, nbsps = name:gsub ('&nbsp;',''); -- count nbsps
    -- There is exactly 1 semicolon per &nbsp; entity, so subtract nbsps
    -- from semicolons to 'escape' them. If additional entities are added,
    -- they also can be subtracted.
    if 1 < commas or 0 < (semicolons - nbsps) then
    utilities.set_message ('maint_mult_names', cfg.special_case_translation [list_name]); -- add a maint message
    end
    end
    end
     
     
    --[[------------------------< N A M E _ C H E C K S >---------------------------
     
    This function calls various name checking functions used to validate the content
    of the various name-holding parameters.


    local err_msg_list_name = list_name:match ("(%w+)List") .. 's list'; -- modify AuthorList or EditorList for use in error messages if necessary
    ]]
    while true do
    last = select_one( args, cfg.aliases[list_name .. '-Last'], 'redundant_parameters', i ); -- search through args for name components beginning at 1
    first = select_one( args, cfg.aliases[list_name .. '-First'], 'redundant_parameters', i );
    link = select_one( args, cfg.aliases[list_name .. '-Link'], 'redundant_parameters', i );
    mask = select_one( args, cfg.aliases[list_name .. '-Mask'], 'redundant_parameters', i );


    last, etal = name_has_etal (last, etal, false); -- find and remove variations on et al.
    local function name_checks (last, first, list_name)
    first, etal = name_has_etal (first, etal, false); -- find and remove variations on et al.
    local accept_name;


    if first and not last then -- if there is a firstn without a matching lastn
    if utilities.is_set (last) then
    table.insert( z.message_tail, { set_error( 'first_missing_last', {err_msg_list_name, i}, true ) } ); -- add this error message
    last, accept_name = utilities.has_accept_as_written (last); -- remove accept-this-as-written markup when it wraps all of <last>
    elseif not first and not last then -- if both firstn and lastn aren't found, are we done?
    count = count + 1; -- number of times we haven't found last and first
    if not accept_name then -- <last> not wrapped in accept-as-written markup
    if 2 <= count then -- two missing names and we give up
    name_has_mult_names (last, list_name); -- check for multiple names in the parameter (last only)
    break; -- normal exit or there is a two-name hole in the list; can't tell which
    name_has_ed_markup (last, list_name); -- check for extraneous 'editor' annotation
    end
    name_is_numeric (last, list_name); -- check for names that are composed of digits and punctuation
    else -- we have last with or without a first
    names[n] = {last = last, first = first, link = link, mask = mask, corporate=false}; -- add this name to our names list (corporate for |vauthors= only)
    n = n + 1; -- point to next location in the names table
    if 1 == count then -- if the previous name was missing
    table.insert( z.message_tail, { set_error( 'missing_name', {err_msg_list_name, i-1}, true ) } ); -- add this error message
    end
    count = 0; -- reset the counter, we're looking for two consecutive missing names
    end
    end
    i = i + 1; -- point to next args location
    end
    end
    return names, etal; -- all done, return our list of names
    end


    -- Populates ID table from arguments using configuration settings
    if utilities.is_set (first) then
    local function extract_ids( args )
    first, accept_name = utilities.has_accept_as_written (first); -- remove accept-this-as-written markup when it wraps all of <first>
    local id_list = {};
     
    for k, v in pairs( cfg.id_handlers ) do
    if not accept_name then -- <first> not wrapped in accept-as-written markup
    v = select_one( args, v.parameters, 'redundant_parameters' );
    name_has_ed_markup (first, list_name); -- check for extraneous 'editor' annotation
    if is_set(v) then id_list[k] = v; end
    name_is_numeric (first, list_name); -- check for names that are composed of digits and punctuation
    end
    end
    end
    return id_list;
     
    return last, first; -- done
    end
    end


    --[[--------------------------< B U I L D _ I D _ L I S T >--------------------------------------------------------


    Takes a table of IDs and turns it into a table of formatted ID outputs.
    --[[----------------------< E X T R A C T _ N A M E S >-------------------------
    Gets name list from the input arguments
     
    Searches through args in sequential order to find |lastn= and |firstn= parameters
    (or their aliases), and their matching link and mask parameters. Stops searching
    when both |lastn= and |firstn= are not found in args after two sequential attempts:
    found |last1=, |last2=, and |last3= but doesn't find |last4= and |last5= then the
    search is done.
     
    This function emits an error message when there is a |firstn= without a matching
    |lastn=.  When there are 'holes' in the list of last names, |last1= and |last3=
    are present but |last2= is missing, an error message is emitted. |lastn= is not
    required to have a matching |firstn=.
     
    When an author or editor parameter contains some form of 'et al.', the 'et al.'
    is stripped from the parameter and a flag (etal) returned that will cause list_people()
    to add the static 'et al.' text from Module:Citation/CS1/Configuration.  This keeps
    'et al.' out of the template's metadata.  When this occurs, an error is emitted.


    ]]
    ]]


    local function build_id_list( id_list, options )
    local function extract_names(args, list_name)
    local new_list, handler = {};
    local names = {}; -- table of names
    local last; -- individual name components
    local first;
    local link;
    local mask;
    local i = 1; -- loop counter/indexer
    local n = 1; -- output table indexer
    local count = 0; -- used to count the number of times we haven't found a |last= (or alias for authors, |editor-last or alias for editors)
    local etal = false; -- return value set to true when we find some form of et al. in an author parameter
     
    local last_alias, first_alias, link_alias; -- selected parameter aliases used in error messaging
    while true do
    last, last_alias = utilities.select_one ( args, cfg.aliases[list_name .. '-Last'], 'err_redundant_parameters', i ); -- search through args for name components beginning at 1
    first, first_alias = utilities.select_one ( args, cfg.aliases[list_name .. '-First'], 'err_redundant_parameters', i );
    link, link_alias = utilities.select_one ( args, cfg.aliases[list_name .. '-Link'], 'err_redundant_parameters', i );
    mask = utilities.select_one ( args, cfg.aliases[list_name .. '-Mask'], 'err_redundant_parameters', i );


    function fallback(k) return { __index = function(t,i) return cfg.id_handlers[k][i] end } end;
    last, etal = name_has_etal (last, etal, false, last_alias); -- find and remove variations on et al.
    first, etal = name_has_etal (first, etal, false, first_alias); -- find and remove variations on et al.
    for k, v in pairs( id_list ) do
    last, first = name_checks (last, first, list_name); -- multiple names, extraneous annotation, etc. checks
    -- fallback to read-only cfg
    handler = setmetatable( { ['id'] = v }, fallback(k) );
    if handler.mode == 'external' then
    if first and not last then -- if there is a firstn without a matching lastn
    table.insert( new_list, {handler.label, external_link_id( handler ) } );
    local alias = first_alias:find ('given', 1, true) and 'given' or 'first'; -- get first or given form of the alias
    elseif handler.mode == 'internal' then
    table.insert (z.message_tail, { utilities.set_message ( 'err_first_missing_last', {
    table.insert( new_list, {handler.label, internal_link_id( handler ) } );
    first_alias, -- param name of alias missing its mate
    elseif handler.mode ~= 'manual' then
    first_alias:gsub (alias, {['first'] = 'last', ['given'] = 'surname'}), -- make param name appropriate to the alias form
    error( cfg.messages['unknown_ID_mode'] );
    }, true ) } ); -- add this error message
    elseif k == 'DOI' then
    elseif not first and not last then -- if both firstn and lastn aren't found, are we done?
    table.insert( new_list, {handler.label, doi( v, options.DoiBroken ) } );
    count = count + 1; -- number of times we haven't found last and first
    elseif k == 'ARXIV' then
    if 2 <= count then -- two missing names and we give up
    table.insert( new_list, {handler.label, arxiv( v, options.Class ) } );
    break; -- normal exit or there is a two-name hole in the list; can't tell which
    elseif k == 'ASIN' then
    table.insert( new_list, {handler.label, amazon( v, options.ASINTLD ) } );
    elseif k == 'LCCN' then
    table.insert( new_list, {handler.label, lccn( v ) } );
    elseif k == 'OL' then
    table.insert( new_list, {handler.label, openlibrary( v ) } );
    elseif k == 'PMC' then
    table.insert( new_list, {handler.label, pmc( v, options.Embargo ) } );
    elseif k == 'PMID' then
    table.insert( new_list, {handler.label, pmid( v ) } );
    elseif k == 'ISMN' then
    table.insert( new_list, {handler.label, ismn( v ) } );
    elseif k == 'ISSN' then
    table.insert( new_list, {handler.label, issn( v ) } );
    elseif k == 'ISBN' then
    local ISBN = internal_link_id( handler );
    if not check_isbn( v ) and not is_set(options.IgnoreISBN) then
    ISBN = ISBN .. set_error( 'bad_isbn', {}, false, " ", "" );
    end
    end
    table.insert( new_list, {handler.label, ISBN } );
    else -- we have last with or without a first
    elseif k == 'USENETID' then
    local result;
    table.insert( new_list, {handler.label, message_id( v ) } );
    link = link_title_ok (link, link_alias, last, last_alias); -- check for improper wiki-markup
    else
    if first then
    error( cfg.messages['unknown_manual_ID'] );
    link = link_title_ok (link, link_alias, first, first_alias); -- check for improper wiki-markup
    end
     
    names[n] = {last = last, first = first, link = link, mask = mask, corporate = false}; -- add this name to our names list (corporate for |vauthors= only)
    n = n + 1; -- point to next location in the names table
    if 1 == count then -- if the previous name was missing
    table.insert( z.message_tail, { utilities.set_message ( 'err_missing_name', {list_name:match ("(%w+)List"):lower(), i - 1}, true ) } ); -- add this error message
    end
    count = 0; -- reset the counter, we're looking for two consecutive missing names
    end
    end
    i = i + 1; -- point to next args location
    end
    end
    function comp( a, b ) -- used in following table.sort()
    return names, etal; -- all done, return our list of names and the etal flag
    return a[1] < b[1];
    end
    table.sort( new_list, comp );
    for k, v in ipairs( new_list ) do
    new_list[k] = v[2];
    end
    return new_list;
    end
    end
     


    --[[--------------------------< C O I N S >--------------------------------------------------------------------


    COinS metadata (see <http://ocoins.info/>) allows automated tools to parse the citation information.
    --[[---------------------< G E T _ I S O 6 3 9 _ C O D E >----------------------
     
    Validates language names provided in |language= parameter if not an ISO639-1 or 639-2 code.
     
    Returns the language name and associated two- or three-character code.  Because
    case of the source may be incorrect or different from the case that WikiMedia uses,
    the name comparisons are done in lower case and when a match is found, the Wikimedia
    version (assumed to be correct) is returned along with the code.  When there is no
    match, we return the original language name string.
     
    mw.language.fetchLanguageNames(<local wiki language>, 'all') returns a list of
    languages that in some cases may include extensions. For example, code 'cbk-zam'
    and its associated name 'Chavacano de Zamboanga' (MediaWiki does not support
    code 'cbk' or name 'Chavacano'.  Most (all?) of these languages are not used a
    'language' codes per se, rather they are used as sub-domain names: cbk-zam.wikipedia.org.
    A list of language names and codes supported by fetchLanguageNames() can be found
    at Template:Citation Style documentation/language/doc
     
    Names that are included in the list will be found if that name is provided in the
    |language= parameter.  For example, if |language=Chavacano de Zamboanga, that name
    will be found with the associated code 'cbk-zam'.  When names are found and the
    associated code is not two or three characters, this function returns only the
    WikiMedia language name.
     
    Some language names have multiple entries under different codes:
    Aromanian has code rup and code roa-rup
    When this occurs, this function returns the language name and the 2- or 3-character code
     
    Adapted from code taken from Module:Check ISO 639-1.


    ]]
    ]]


    local function COinS(data, class)
    local function get_iso639_code (lang, this_wiki_code)
    if 'table' ~= type(data) or nil == next(data) then
    if cfg.lang_name_remap[lang:lower()] then -- if there is a remapped name (because MediaWiki uses something that we don't think is correct)
    return '';
    return cfg.lang_name_remap[lang:lower()][1], cfg.lang_name_remap[lang:lower()][2]; -- for this language 'name', return a possibly new name and appropriate code
    end
    end
    local ietf_code; -- because some languages have both IETF-like codes and ISO 639-like codes
    local ietf_name;
    local ctx_ver = "Z39.88-2004";
    local langlc = mw.ustring.lower (lang); -- lower-case version for comparisons
     
    -- treat table strictly as an array with only set values.
    for code, name in pairs (cfg.languages) do -- scan the list to see if we can find our language
    local OCinSoutput = setmetatable( {}, {
    if langlc == mw.ustring.lower (name) then
    __newindex = function(self, key, value)
    if 2 == #code or 3 == #code then -- two- or three-character codes only; IETF extensions not supported
    if is_set(value) then
    return name, code; -- so return the name and the code
    rawset( self, #self+1, table.concat{ key, '=', mw.uri.encode( remove_wiki_link( value ) ) } );
    end
    end
    ietf_code = code; -- remember that we found an IETF-like code and save its name
    ietf_name = name; -- but keep looking for a 2- or 3-char code
    end
    end
    });
    end
    -- didn't find name with 2- or 3-char code; if IETF-like code found return
    if in_array (class, {'citation', 'conference', 'interview', 'press release'}) and is_set(data.Periodical) then
    return ietf_code and ietf_name or lang; -- associated name; return original language text else
    OCinSoutput.rft_val_fmt = "info:ofi/fmt:kev:mtx:journal";
    end
    OCinSoutput["rft.genre"] = "article";
     
    OCinSoutput["rft.jtitle"] = data.Periodical;
     
    OCinSoutput["rft.atitle"] = data.Title;
    --[[-------------------< L A N G U A G E _ P A R A M E T E R >------------------
    elseif in_array (class, {'arxiv', 'journal', 'news'}) then
    OCinSoutput.rft_val_fmt = "info:ofi/fmt:kev:mtx:journal";
    if 'arxiv' == class then
    OCinSoutput["rft.genre"] = "preprint"; -- cite arxiv
    else
    OCinSoutput["rft.genre"] = "article";
    end
    OCinSoutput["rft.jtitle"] = data.Periodical;
    OCinSoutput["rft.atitle"] = data.Title;
    else
    OCinSoutput.rft_val_fmt = "info:ofi/fmt:kev:mtx:book";
    if is_set (data.Chapter) then
    OCinSoutput["rft.genre"] = "bookitem";
    OCinSoutput["rft.atitle"] = data.Chapter;
    else
    OCinSoutput["rft.genre"] = "book"
    end
    OCinSoutput["rft.btitle"] = data.Title;
    end


    OCinSoutput["rft.place"] = data.PublicationPlace;
    Gets language name from a provided two- or three-character ISO 639 code. If a code
    OCinSoutput["rft.date"] = data.Date;
    is recognized by MediaWiki, use the returned name; if not, then use the value that
    OCinSoutput["rft.series"] = data.Series;
    was provided with the language parameter.
    OCinSoutput["rft.volume"] = data.Volume;
    OCinSoutput["rft.issue"] = data.Issue;
    OCinSoutput["rft.pages"] = data.Pages;
    OCinSoutput["rft.edition"] = data.Edition;
    OCinSoutput["rft.pub"] = data.PublisherName;
    for k, v in pairs( data.ID_list ) do
    local id, value = cfg.id_handlers[k].COinS;
    if k == 'ISBN' then value = clean_isbn( v ); else value = v; end
    if string.sub( id or "", 1, 4 ) == 'info' then
    OCinSoutput["rft_id"] = table.concat{ id, "/", v };
    else
    OCinSoutput[ id ] = value;
    end
    end
    local last, first;
    for k, v in ipairs( data.Authors ) do
    last, first = v.last, v.first;
    if k == 1 then -- for the first author name only
    if is_set(last)  and is_set(first) then -- set these COinS values if |first= and |last= specify the first author name
    OCinSoutput["rft.aulast"] = last;
    OCinSoutput["rft.aufirst"] = first;
    elseif is_set(last) then
    OCinSoutput["rft.au"] = last; -- otherwise use this form for the first name
    end
    else -- for all other authors
    if is_set(last) and is_set(first) then
    OCinSoutput["rft.au"] = table.concat{ last, ", ", first };
    elseif is_set(last) then
    OCinSoutput["rft.au"] = last;
    end
    end
    end


    OCinSoutput.rft_id = data.URL;
    When |language= contains a recognized language (either code or name), the page is
    OCinSoutput.rfr_id = table.concat{ "info:sid/", mw.site.server:match( "[^/]*$" ), ":", data.RawPage };
    assigned to the category for that code: Category:Norwegian-language sources (no).
    OCinSoutput = setmetatable( OCinSoutput, nil );
    For valid three-character code languages, the page is assigned to the single category
    for '639-2' codes: Category:CS1 ISO 639-2 language sources.
    -- sort with version string always first, and combine.
    table.sort( OCinSoutput );
    table.insert( OCinSoutput, 1, "ctx_ver=" .. ctx_ver );  -- such as "Z39.88-2004"
    return table.concat(OCinSoutput, "&");
    end


    Languages that are the same as the local wiki are not categorized.  MediaWiki does
    not recognize three-character equivalents of two-character codes: code 'ar' is
    recognized but code 'ara' is not.


    --[[--------------------------< G E T _ I S O 6 3 9 _ C O D E >------------------------------------------------
    This function supports multiple languages in the form |language=nb, French, th
    where the language names or codes are separated from each other by commas with
    optional space characters.


    Validates language names provided in |language= parameter if not an ISO639-1 code.  Handles the special case that is Norwegian where
    ]]
    ISO639-1 code 'no' is mapped to language name 'Norwegian Bokmål' by Extention:CLDR.


    Returns the language name and associated ISO639-1 code.  Because case of the source may be incorrect or different from the case that Wikimedia
    local function language_parameter (lang)
    uses, the name comparisons are done in lower case and when a match is found, the Wikimedia version (assumed to be correct) is returned along
    local code; -- the two- or three-character language code
    with the code.  When there is no match, we return the original language name string.
    local name; -- the language name
    local language_list = {}; -- table of language names to be rendered
    local names_table = {}; -- table made from the value assigned to |language=


    mw.language.fetchLanguageNames() will return a list of languages that aren't part of ISO639-1. Names that aren't ISO639-1 but that are included
    local this_wiki_name = mw.language.fetchLanguageName (cfg.this_wiki_code, cfg.this_wiki_code); -- get this wiki's language name
    in the list will be found if that name is provided in the |language= parameter.  For example, if |language=Samaritan Aramaic, that name will be
    found with the associated code 'sam', not an ISO639-1 code.  When names are found and the associated code is not two characters, this function
    returns only the Wikimedia language name.


    Adapted from code taken from Module:Check ISO 639-1.
    names_table = mw.text.split (lang, '%s*,%s*'); -- names should be a comma separated list


    ]]
    for _, lang in ipairs (names_table) do -- reuse lang
    name = cfg.lang_code_remap[lang:lower()]; -- first see if this is a code that is not supported by MediaWiki but is in remap


    local function get_iso639_code (lang)
    if name then -- there was a remapped code so
    if 'norwegian' == lang:lower() then -- special case related to Wikimedia remap of code 'no' at Extension:CLDR
    if not lang:match ('^%a%a%a?%-x%-%a+$') then -- if not a private IETF tag
    return 'Norwegian', 'no'; -- Make sure rendered version is properly capitalized
    lang = lang:gsub ('^(%a%a%a?)%-.*', '%1'); -- strip IETF tags from code
    end
    end
    else
    local languages = mw.language.fetchLanguageNames('en', 'all') -- get a list of language names known to Wikimedia
    lang = lang:gsub ('^(%a%a%a?)%-.*', '%1'); -- strip any IETF-like tags from code
    -- ('all' is required for North Ndebele, South Ndebele, and Ojibwa)
    if 2 == lang:len() or 3 == lang:len() then -- if two-or three-character code
    local langlc = mw.ustring.lower(lang); -- lower case version for comparisons
    name = mw.language.fetchLanguageName (lang:lower(), cfg.this_wiki_code); -- get language name if |language= is a proper code
    for code, name in pairs(languages) do -- scan the list to see if we can find our language
    if langlc == mw.ustring.lower(name) then
    if 2 ~= code:len() then -- ISO639-1 codes only
    return name; -- so return the name but not the code
    end
    end
    return name, code; -- found it, return name to ensure proper capitalization and the ISO639-1 code
    end
    end
    end
    return lang; -- not valid language; return language in original case and nil for ISO639-1 code
    end
    --[[--------------------------< L A N G U A G E _ P A R A M E T E R >------------------------------------------
    Get language name from ISO639-1 code value provided.  If a code is valid use the returned name; if not, then use the value that was provided with the language parameter.


    There is an exception.  There are three ISO639-1 codes for Norewegian language variants.  There are two official variants: Norwegian Bokmål (code 'nb') and
    if utilities.is_set (name) then -- if |language= specified a valid code
    Norwegian Nynorsk (code 'nn').  The third, code 'no',  is defined by ISO639-1 as 'Norwegian' though in Norway this is pretty much meaningless.  However, it appears
    that on enwiki, editors are for the most part unaware of the nb and nn variants (compare page counts for these variants at Category:Articles with non-English-language external links.
     
    Because Norwegian Bokmål is the most common language variant, Media wiki has been modified to return Norwegian Bokmål for ISO639-1 code 'no'. Here we undo that and
    return 'Norwegian' when editors use |language=no.  We presume that editors don't know about the variants or can't descriminate between them.
     
    See Help talk:Citation Style_1#An ISO 639-1 language name test
     
    When |language= contains a valid ISO639-1 code, the page is assigned to the category for that code: Category:Norwegian-language sources (no) if
    the page is a mainspace page and the ISO639-1 code is not 'en'.  Similarly, if the  parameter is |language=Norwegian, it will be categorized in the same way.
     
    This function supports multiple languages in the form |language=nb, French, th where the language names or codes are separated from each other by commas.
     
    ]]
     
    local function language_parameter (lang)
    local code; -- the ISO639-1 two character code
    local name; -- the language name
    local language_list = {}; -- table of language names to be rendered
    local names_table = {}; -- table made from the value assigned to |language=
     
    names_table = mw.text.split (lang, '%s*,%s*'); -- names should be a comma separated list
     
    for _, lang in ipairs (names_table) do -- reuse lang
     
    if 2 == lang:len() then -- ISO639-1 language code are 2 characters (fetchLanguageName also supports 3 character codes)
    name = mw.language.fetchLanguageName( lang:lower(), "en" ); -- get ISO 639-1 language name if Language is a proper code
    end
    if is_set (name) then -- if Language specified a valid ISO639-1 code
    code = lang:lower(); -- save it
    code = lang:lower(); -- save it
    else
    else
    name, code = get_iso639_code (lang); -- attempt to get code from name (assign name here so that we are sure of proper capitalization)
    name, code = get_iso639_code (lang, cfg.this_wiki_code); -- attempt to get code from name (assign name here so that we are sure of proper capitalization)
    end
    end
    if is_set (code) then
    if utilities.is_set (code) then -- only 2- or 3-character codes
    if 'no' == code then name = 'Norwegian' end; -- override wikimedia when code is 'no'
    name = cfg.lang_code_remap[code] or name; -- override wikimedia when they misuse language codes/names
    if 'en' ~= code then -- English not the language
     
    add_prop_cat ('foreign_lang_source', {name, code})
    if cfg.this_wiki_code ~= code then -- when the language is not the same as this wiki's language
    if 2 == code:len() then -- and is a two-character code
    utilities.add_prop_cat ('foreign_lang_source' .. code, {name, code}); -- categorize it; code appended to allow for multiple language categorization
    else -- or is a recognized language (but has a three-character code)
    utilities.add_prop_cat ('foreign_lang_source_2' .. code, {code}); -- categorize it differently TODO: support multiple three-character code categories per cs1|2 template
    end
    elseif cfg.local_lang_cat_enable then -- when the language and this wiki's language are the same and categorization is enabled
    utilities.add_prop_cat ('local_lang_source', {name, code}); -- categorize it
    end
    end
    else
    else
    add_maint_cat ('unknown_lang'); -- add maint category if not already added
    utilities.set_message ('maint_unknown_lang'); -- add maint category if not already added
    end
    end
    Line 1,856: Line 1,653:
    name = ''; -- so we can reuse it
    name = ''; -- so we can reuse it
    end
    end
    code = #language_list -- reuse code as number of languages in the list
    name = utilities.make_sep_list (#language_list, language_list);
    if 2 >= code then
     
    name = table.concat (language_list, ' and ') -- insert '<space>and<space>' between two language names
    if this_wiki_name == name then
    elseif 2 < code then
    return ''; -- if one language and that language is this wiki's return an empty string (no annotation)
    language_list[code] = 'and ' .. language_list[code]; -- prepend last name with 'and<space>'
    name = table.concat (language_list, ', ') -- and concatenate with '<comma><space>' separators
    end
    if 'English' == name then
    return ''; -- if one language and that language is English return an enpty string (no annotation)
    end
    end
    return (" " .. wrap_msg ('language', name)); -- otherwise wrap with '(in ...)'
    return (" " .. wrap_msg ('language', name)); -- otherwise wrap with '(in ...)'
    --[[ TODO: should only return blank or name rather than full list
    so we can clean up the bunched parenthetical elements Language, Type, Format
    ]]
    end
    end


    --[[--------------------------< S E T _ C S 1 _ S T Y L E >----------------------------------------------------
    --[[-----------------------< S E T _ C S _ S T Y L E >--------------------------
     
    Gets the default CS style configuration for the given mode.
    Set style settings for CS1 citation templates. Returns separator and postscript settings
    Returns default separator and either postscript as passed in or the default.
     
    In CS1, the default postscript and separator are '.'.
    In CS2, the default postscript is the empty string and the default separator is ','.
    ]]
    ]]
     
    local function set_cs_style (postscript, mode)
    local function set_cs1_style (ps)
    if utilities.is_set(postscript) then
    if not is_set (ps) then -- unless explicitely set to something
    -- emit a maintenance message if user postscript is the default cs1 postscript
    ps = '.'; -- terminate the rendered citation with a period
    -- we catch the opposite case for cs2 in set_style
    if mode == 'cs1' and postscript == cfg.presentation['ps_' .. mode] then
    utilities.set_message ('maint_postscript');
    end
    else
    postscript = cfg.presentation['ps_' .. mode];
    end
    end
    return '.', ps; -- separator is a full stop
    return cfg.presentation['sep_' .. mode], postscript;
    end
    end


    --[[--------------------------< S E T _ C S 2 _ S T Y L E >----------------------------------------------------
    --[[--------------------------< S E T _ S T Y L E >-----------------------------
     
    Sets the separator and postscript styles. Checks the |mode= first and the
    Set style settings for CS2 citation templates. Returns separator, postscript, ref settings
    #invoke CitationClass second. Removes the postscript if postscript == none.
     
    ]]
    ]]
     
    local function set_style (mode, postscript, cite_class)
    local function set_cs2_style (ps, ref)
    if not is_set (ps) then -- if |postscript= has not been set, set cs2 default
    ps = ''; -- make sure it isn't nil
    end
    if not is_set (ref) then -- if |ref= is not set
    ref = "harv"; -- set default |ref=harv
    end
    return ',', ps, ref; -- separator is a comma
    end
     
    --[[--------------------------< G E T _ S E T T I N G S _ F R O M _ C I T E _ C L A S S >----------------------
     
    When |mode= is not set or when its value is invalid, use config.CitationClass and parameter values to establish
    rendered style.
     
    ]]
     
    local function get_settings_from_cite_class (ps, ref, cite_class)
    local sep;
    local sep;
    if (cite_class == "citation") then -- for citation templates (CS2)
    if 'cs2' == mode then
    sep, ps, ref = set_cs2_style (ps, ref);
    sep, postscript = set_cs_style (postscript, 'cs2');
    else -- not a citation template so CS1
    elseif 'cs1' == mode then
    sep, ps = set_cs1_style (ps);
    sep, postscript = set_cs_style (postscript, 'cs1');
    elseif 'citation' == cite_class then
    sep, postscript = set_cs_style (postscript, 'cs2');
    else
    sep, postscript = set_cs_style (postscript, 'cs1');
    end
    end


    return sep, ps, ref -- return them all
    if cfg.keywords_xlate[postscript:lower()] == 'none' then
    end
    -- emit a maintenance message if user postscript is the default cs2 postscript
     
    -- we catch the opposite case for cs1 in set_cs_style
    --[[--------------------------< S E T _ S T Y L E >------------------------------------------------------------
    if 'cs2' == mode or 'citation' == cite_class then
     
    utilities.set_message ('maint_postscript');
    Establish basic style settings to be used when rendering the citation.  Uses |mode= if set and valid or uses
    end
    config.CitationClass from the template's #invoke: to establish style.
    postscript = '';
     
    ]]
     
    local function set_style (mode, ps, ref, cite_class)
    local sep;
    if 'cs2' == mode then -- if this template is to be rendered in CS2 (citation) style
    sep, ps, ref = set_cs2_style (ps, ref);
    elseif 'cs1' == mode then -- if this template is to be rendered in CS1 (cite xxx) style
    sep, ps = set_cs1_style (ps);
    else -- anything but cs1 or cs2
    sep, ps, ref = get_settings_from_cite_class (ps, ref, cite_class); -- get settings based on the template's CitationClass
    end
    if 'none' == ps:lower() then -- if assigned value is 'none' then
    ps = ''; -- set to empty string
    end
    end
    return sep, ps, ref
    return sep, postscript
    end
    end


    --[=[-------------------------< I S _ P D F >------------------------------------------------------------------
    --[=[-------------------------< I S _ P D F >-----------------------------------


    Determines if a url has the file extension that is one of the pdf file extensions used by [[MediaWiki:Common.css]] when
    Determines if a URL has the file extension that is one of the PDF file extensions
    applying the pdf icon to external links.
    used by [[MediaWiki:Common.css]] when applying the PDF icon to external links.


    returns true if file extension is one of the recognized extension, else false
    returns true if file extension is one of the recognized extensions, else false


    ]=]
    ]=]


    local function is_pdf (url)
    local function is_pdf (url)
    return url:match ('%.pdf[%?#]?') or url:match ('%.PDF[%?#]?');
    return url:match ('%.pdf$') or url:match ('%.PDF$') or
    url:match ('%.pdf[%?#]') or url:match ('%.PDF[%?#]') or
    url:match ('%.PDF&#035') or url:match ('%.pdf&#035');
    end
    end


    --[[--------------------------< S T Y L E _ F O R M A T >------------------------------------------------------


    Applies css style to |format=, |chapter-format=, etc.  Also emits an error message if the format parameter does
    --[[--------------------------< S T Y L E _ F O R M A T >-----------------------
    not have a matching url parameter.  If the format parameter is not set and the url contains a file extension that
     
    is recognized as a pdf document by MediaWiki's commons.css, this code will set the format parameter to (PDF) with
    Applies CSS style to |format=, |chapter-format=, etc.  Also emits an error message
    if the format parameter does not have a matching URL parameter.  If the format parameter
    is not set and the URL contains a file extension that is recognized as a PDF document
    by MediaWiki's commons.css, this code will set the format parameter to (PDF) with
    the appropriate styling.
    the appropriate styling.


    Line 1,963: Line 1,739:


    local function style_format (format, url, fmt_param, url_param)
    local function style_format (format, url, fmt_param, url_param)
    if is_set (format) then
    if utilities.is_set (format) then
    format = wrap_style ('format', format); -- add leading space, parenthases, resize
    format = utilities.wrap_style ('format', format); -- add leading space, parentheses, resize
    if not is_set (url) then
    if not utilities.is_set (url) then
    format = format .. set_error( 'format_missing_url', {fmt_param, url_param} ); -- add an error message
    format = format .. ' ' .. utilities.set_message ( 'err_format_missing_url', {fmt_param, url_param} ); -- add an error message
    end
    end
    elseif is_pdf (url) then -- format is not set so if url is a pdf file then
    elseif is_pdf (url) then -- format is not set so if URL is a PDF file then
    format = wrap_style ('format', 'PDF'); -- set format to pdf
    format = utilities.wrap_style ('format', 'PDF'); -- set format to PDF
    else
    else
    format = ''; -- empty string for concatenation
    format = ''; -- empty string for concatenation
    Line 1,976: Line 1,752:
    end
    end


    --[[--------------------------< G E T _ D I S P L A Y _ A U T H O R S _ E D I T O R S >------------------------


    Returns a number that may or may not limit the length of the author or editor name lists.
    --[[---------------------< G E T _ D I S P L A Y _ N A M E S >------------------
     
    Returns a number that defines the number of names displayed for author and editor
    name lists and a Boolean flag to indicate when et al. should be appended to the name list.


    When the value assigned to |display-authors= is a number greater than or equal to zero, return the number and
    When the value assigned to |display-xxxxors= is a number greater than or equal to zero,
    the previous state of the 'etal' flag (false by default but may have been set to true if the name list contains
    return the number and the previous state of the 'etal' flag (false by default
    some variant of the text 'et al.').
    but may have been set to true if the name list contains some variant of the text 'et al.').


    When the value assigned to |display-authors= is the keyword 'etal', return a number that is one greater than the
    When the value assigned to |display-xxxxors= is the keyword 'etal', return a number
    number of authors in the list and set the 'etal' flag true. This will cause the list_people() to display all of
    that is one greater than the number of authors in the list and set the 'etal' flag true.
    the names in the name list followed by 'et al.'
    This will cause the list_people() to display all of the names in the name list followed by 'et al.'


    In all other cases, returns nil and the previous state of the 'etal' flag.
    In all other cases, returns nil and the previous state of the 'etal' flag.
    inputs:
    max: A['DisplayAuthors'] or A['DisplayEditors']; a number or some flavor of etal
    count: #a or #e
    list_name: 'authors' or 'editors'
    etal: author_etal or editor_etal


    ]]
    ]]


    local function get_display_authors_editors (max, count, list_name, etal)
    local function get_display_names (max, count, list_name, etal, param)
    if is_set (max) then
    if utilities.is_set (max) then
    if 'etal' == max:lower():gsub("[ '%.]", '') then -- the :gsub() portion makes 'etal' from a variety of 'et al.' spellings and stylings
    if 'etal' == max:lower():gsub("[ '%.]", '') then -- the :gsub() portion makes 'etal' from a variety of 'et al.' spellings and stylings
    max = count + 1; -- number of authors + 1 so display all author name plus et al.
    max = count + 1; -- number of authors + 1 so display all author name plus et al.
    Line 1,999: Line 1,783:
    elseif max:match ('^%d+$') then -- if is a string of numbers
    elseif max:match ('^%d+$') then -- if is a string of numbers
    max = tonumber (max); -- make it a number
    max = tonumber (max); -- make it a number
    if max >= count and 'authors' == list_name then -- AUTHORS ONLY -- if |display-xxxxors= value greater than or equal to number of authors/editors
    if max >= count then -- if |display-xxxxors= value greater than or equal to number of authors/editors
    add_maint_cat ('disp_auth_ed', list_name);
    table.insert( z.message_tail, {utilities.set_message ('err_disp_name', {param, max}, true)}); -- add error message
    max = nil;
    end
    end
    else -- not a valid keyword or number
    else -- not a valid keyword or number
    table.insert( z.message_tail, { set_error( 'invalid_param_val', {'display-' .. list_name, max}, true ) } ); -- add error message
    table.insert( z.message_tail, {utilities.set_message ('err_disp_name', {param, max}, true)}); -- add error message
    max = nil; -- unset
    max = nil; -- unset; as if |display-xxxxors= had not been set
    end
    end
    elseif 'authors' == list_name then -- AUTHORS ONLY need to clear implicit et al category
    max = count + 1; -- number of authors + 1
    end
    end
    Line 2,013: Line 1,796:
    end
    end


    --[[--------------------------< E X T R A _ T E X T _ I N _ P A G E _ C H E C K >------------------------------


    Adds page to Category:CS1 maint: extra text if |page= or |pages= has what appears to be some form of p. or pp.  
    --[[----------< E X T R A _ T E X T _ I N _ P A G E _ C H E C K >---------------
    abbreviation in the first characters of the parameter content.
     
    Adds error if |page=, |pages=, |quote-page=, |quote-pages= has what appears to be
    some form of p. or pp. abbreviation in the first characters of the parameter content.


    check Page and Pages for extraneous p, p., pp, and pp. at start of parameter value:
    check page for extraneous p, p., pp, pp., pg, pg. at start of parameter value:
    good pattern: '^P[^%.P%l]' matches when |page(s)= begins PX or P# but not Px where x and X are letters and # is a dgiit
    good pattern: '^P[^%.P%l]' matches when page begins PX or P# but not Px
    bad pattern: '^[Pp][Pp]' matches matches when |page(s)= begins pp or pP or Pp or PP
          where x and X are letters and # is a digit
    bad pattern: '^[Pp][PpGg]' matches when page begins pp, pP, Pp, PP, pg, pG, Pg, PG


    ]]
    ]]


    local function extra_text_in_page_check (page, nopp)
    local function extra_text_in_page_check (val, name)
    -- local good_pattern = '^P[^%.P%l]';
    if not val:match (cfg.vol_iss_pg_patterns.good_ppattern) then
    local good_pattern = '^P[^%.Pp]'; -- ok to begin with uppercase P: P7 (pg 7 of section P) but not p123 (page 123) TODO: add Gg for PG or Pg?
    for _, pattern in ipairs (cfg.vol_iss_pg_patterns.bad_ppatterns) do -- spin through the selected sequence table of patterns
    -- local bad_pattern = '^[Pp][Pp]';
    if val:match (pattern) then -- when a match, error so
    local bad_pattern = '^[Pp]?[Pp]%.?[ %d]';
    table.insert (z.message_tail, {utilities.set_message ('err_extra_text_pages', {name}, true)}); -- add error message
    return; -- and done
    end
    end
    end
    end


    if is_set (nopp) then -- don't bother checking if |nopp= is set
     
    --[[--------------------------< E X T R A _ T E X T _ I N _ V O L _ I S S _ C H E C K >------------------------
     
    Adds error if |volume= or |issue= has what appears to be some form of redundant 'type' indicator.
     
    For |volume=:
    'V.', or 'Vol.' (with or without the dot) abbreviations or 'Volume' in the first characters of the parameter
    content (all case insensitive). 'V' and 'v' (without the dot) are presumed to be roman numerals so
    are allowed.
     
    For |issue=:
    'No.', 'I.', 'Iss.' (with or without the dot) abbreviations, or 'Issue' in the first characters of the
    parameter content (all case insensitive).
    Single character values ('v', 'i', 'n') allowed when not followed by separator character ('.', ':', '=', or
    whitespace character) – param values are trimmed of whitespace by MediaWiki before delivered to the module.
    <val> is |volume= or |issue= parameter value
    <name> is |volume= or |issue= parameter name for error message
    <selector> is 'v' for |volume=, 'i' for |issue=
     
    sets error message on failure; returns nothing
     
    ]]
     
    local function extra_text_in_vol_iss_check (val, name, selector)
    if not utilities.is_set (val) then
    return;
    return;
    end
    end
    local patterns = 'v' == selector and cfg.vol_iss_pg_patterns.vpatterns or cfg.vol_iss_pg_patterns.ipatterns;


    if not page:match (good_pattern) and (page:match (bad_pattern) or  page:match ('^[Pp]ages?')) then
    local handler = 'v' == selector and 'err_extra_text_volume' or 'err_extra_text_issue';
    add_maint_cat ('extra_text');
    val = val:lower(); -- force parameter value to lower case
    for _, pattern in ipairs (patterns) do -- spin through the selected sequence table of patterns
    if val:match (pattern) then -- when a match, error so
    table.insert (z.message_tail, {utilities.set_message (handler, {name}, true)}); -- add error message
    return; -- and done
    end
    end
    end
    -- if Page:match ('^[Pp]?[Pp]%.?[ %d]') or  Page:match ('^[Pp]ages?[ %d]') or
    -- Pages:match ('^[Pp]?[Pp]%.?[ %d]') or  Pages:match ('^[Pp]ages?[ %d]') then
    -- add_maint_cat ('extra_text');
    -- end
    end
    end




    --[[--------------------------< P A R S E _ V A U T H O R S _ V E D I T O R S >--------------------------------
    --[=[-------------------------< G E T _ V _ N A M E _ T A B L E >----------------------------------------------


    This function extracts author / editor names from |vauthors= or |veditors= and finds matching |xxxxor-maskn= and
    split apart a |vauthors= or |veditors= parameter.  This function allows for corporate names, wrapped in doubled
    |xxxxor-linkn= in args.  It then returns a table of assembled names just as extract_names() does.
    parentheses to also have commas; in the old version of the code, the doubled parentheses were included in the
    rendered citation and in the metadata.  Individual author names may be wikilinked


    Author / editor names in |vauthors= or |veditors= must be in Vancouver system style. Corporate or institutional names
    |vauthors=Jones AB, [[E. B. White|White EB]], ((Black, Brown, and Co.))
    may sometimes be required and because such names will often fail the is_good_vanc_name() and other format compliance
    tests, are wrapped in doubled paranethese ((corporate name)) to suppress the format tests.


    This function sets the vancouver error when a reqired comma is missing and when there is a space between an author's initials.
    ]=]


    ]]
    local function get_v_name_table (vparam, output_table, output_link_table)
    local name_table = mw.text.split(vparam, "%s*,%s*"); -- names are separated by commas
    local wl_type, label, link; -- wl_type not used here; just a placeholder
    local i = 1;
    while name_table[i] do
    if name_table[i]:match ('^%(%(.*[^%)][^%)]$') then -- first segment of corporate with one or more commas; this segment has the opening doubled parentheses
    local name = name_table[i];
    i = i + 1; -- bump indexer to next segment
    while name_table[i] do
    name = name .. ', ' .. name_table[i]; -- concatenate with previous segments
    if name_table[i]:match ('^.*%)%)$') then -- if this table member has the closing doubled parentheses
    break; -- and done reassembling so
    end
    i = i + 1; -- bump indexer
    end
    table.insert (output_table, name); -- and add corporate name to the output table
    table.insert (output_link_table, ''); -- no wikilink
    else
    wl_type, label, link = utilities.is_wikilink (name_table[i]); -- wl_type is: 0, no wl (text in label variable); 1, [[D]]; 2, [[L|D]]
    table.insert (output_table, label); -- add this name
    if 1 == wl_type then
    table.insert (output_link_table, label); -- simple wikilink [[D]]
    else
    table.insert (output_link_table, link); -- no wikilink or [[L|D]]; add this link if there is one, else empty string
    end
    end
    i = i + 1;
    end
    return output_table;
    end
     
     
    --[[--------------------------< P A R S E _ V A U T H O R S _ V E D I T O R S >--------------------------------
     
    This function extracts author / editor names from |vauthors= or |veditors= and finds matching |xxxxor-maskn= and
    |xxxxor-linkn= in args.  It then returns a table of assembled names just as extract_names() does.
     
    Author / editor names in |vauthors= or |veditors= must be in Vancouver system style. Corporate or institutional names
    may sometimes be required and because such names will often fail the is_good_vanc_name() and other format compliance
    tests, are wrapped in doubled parentheses ((corporate name)) to suppress the format tests.
     
    Supports generational suffixes Jr, 2nd, 3rd, 4th–6th.
     
    This function sets the Vancouver error when a required comma is missing and when there is a space between an author's initials.
     
    ]]


    local function parse_vauthors_veditors (args, vparam, list_name)
    local function parse_vauthors_veditors (args, vparam, list_name)
    local names = {}; -- table of names assembled from |vauthors=, |author-maskn=, |author-linkn=
    local names = {}; -- table of names assembled from |vauthors=, |author-maskn=, |author-linkn=
    local v_name_table = {};
    local v_name_table = {};
    local v_link_table = {}; -- when name is wikilinked, targets go in this table
    local etal = false; -- return value set to true when we find some form of et al. vauthors parameter
    local etal = false; -- return value set to true when we find some form of et al. vauthors parameter
    local last, first, link, mask;
    local last, first, link, mask, suffix;
    local corporate = false;
    local corporate = false;


    vparam, etal = name_has_etal (vparam, etal, true); -- find and remove variations on et al. do not categorize (do it here because et al. might have a period)
    vparam, etal = name_has_etal (vparam, etal, true); -- find and remove variations on et al. do not categorize (do it here because et al. might have a period)
    if vparam:find ('%[%[') or vparam:find ('%]%]') then -- no wikilinking vauthors names
    v_name_table = get_v_name_table (vparam, v_name_table, v_link_table); -- names are separated by commas
    add_vanc_error ();
    end
    v_name_table = mw.text.split(vparam, "%s*,%s*") -- names are separated by commas


    for i, v_name in ipairs(v_name_table) do
    for i, v_name in ipairs(v_name_table) do
    if v_name:match ('^%(%(.+%)%)$') then -- corporate authors are wrapped in doubled parenthese to supress vanc formatting and error detection
    first = ''; -- set to empty string for concatenation and because it may have been set for previous author/editor
    first = ''; -- set to empty string for concatenation and because it may have been set for previous author/editor
    local accept_name;
    last = v_name:match ('^%(%((.+)%)%)$')
    v_name, accept_name = utilities.has_accept_as_written (v_name); -- remove accept-this-as-written markup when it wraps all of <v_name>
    corporate = true;
     
    if accept_name then
    last = v_name;
    corporate = true; -- flag used in list_people()
    elseif string.find(v_name, "%s") then
    elseif string.find(v_name, "%s") then
        lastfirstTable = {}
    if v_name:find('[;%.]') then -- look for commonly occurring punctuation characters;
        lastfirstTable = mw.text.split(v_name, "%s")
    add_vanc_error (cfg.err_msg_supl.punctuation, i);
        first = table.remove(lastfirstTable); -- removes and returns value of last element in table which should be author intials
    end
        last = table.concat(lastfirstTable, " ") -- returns a string that is the concatenation of all other names that are not initials
    local lastfirstTable = {}
        if mw.ustring.match (last, '%a+%s+%u+%s+%a+') or mw.ustring.match (v_name, ' %u %u$') then
    lastfirstTable = mw.text.split(v_name, "%s+")
    add_vanc_error (); -- matches last II last; the case when a comma is missing or a space between two intiials
    first = table.remove(lastfirstTable); -- removes and returns value of last element in table which should be initials or generational suffix
     
    if not mw.ustring.match (first, '^%u+$') then -- mw.ustring here so that later we will catch non-Latin characters
    suffix = first; -- not initials so assume that whatever we got is a generational suffix
    first = table.remove(lastfirstTable); -- get what should be the initials from the table
    end
    last = table.concat(lastfirstTable, ' ') -- returns a string that is the concatenation of all other names that are not initials and generational suffix
    if not utilities.is_set (last) then
    first = ''; -- unset
    last = v_name; -- last empty because something wrong with first
    add_vanc_error (cfg.err_msg_supl.name, i);
    end
    if mw.ustring.match (last, '%a+%s+%u+%s+%a+') then
    add_vanc_error (cfg.err_msg_supl['missing comma'], i); -- matches last II last; the case when a comma is missing
    end
    if mw.ustring.match (v_name, ' %u %u$') then -- this test is in the wrong place TODO: move or replace with a more appropriate test
    add_vanc_error (cfg.err_msg_supl.initials, i); -- matches a space between two initials
    end
    end
    else
    else
    first = ''; -- set to empty string for concatenation and because it may have been set for previous author/editor
    last = v_name; -- last name or single corporate name?  Doesn't support multiword corporate names? do we need this?
    last = v_name; -- last name or single corporate name?  Doesn't support multiword corporate names? do we need this?
    end
    end
    if is_set (first) and not mw.ustring.match (first, "^%u?%u$") then -- first shall contain one or two upper-case letters, nothing else
    if utilities.is_set (first) then
    add_vanc_error ();
    if not mw.ustring.match (first, "^%u?%u$") then -- first shall contain one or two upper-case letters, nothing else
    add_vanc_error (cfg.err_msg_supl.initials, i); -- too many initials; mixed case initials (which may be ok Romanization); hyphenated initials
    end
    is_good_vanc_name (last, first, suffix, i); -- check first and last before restoring the suffix which may have a non-Latin digit
    if utilities.is_set (suffix) then
    first = first .. ' ' .. suffix; -- if there was a suffix concatenate with the initials
    suffix = ''; -- unset so we don't add this suffix to all subsequent names
    end
    else
    if not corporate then
    is_good_vanc_name (last, '', nil, i);
    end
    end
    end
    -- this from extract_names ()
     
    link = select_one( args, cfg.aliases[list_name .. '-Link'], 'redundant_parameters', i );
    link = utilities.select_one ( args, cfg.aliases[list_name .. '-Link'], 'err_redundant_parameters', i ) or v_link_table[i];
    mask = select_one( args, cfg.aliases[list_name .. '-Mask'], 'redundant_parameters', i );
    mask = utilities.select_one ( args, cfg.aliases[list_name .. '-Mask'], 'err_redundant_parameters', i );
    names[i] = {last = last, first = first, link = link, mask = mask, corporate=corporate}; -- add this assembled name to our names list
    names[i] = {last = last, first = first, link = link, mask = mask, corporate = corporate}; -- add this assembled name to our names list
    end
    end
    return names, etal; -- all done, return our list of names
    return names, etal; -- all done, return our list of names
    end
    end


    --[[--------------------------< S E L E C T _ A U T H O R _ E D I T O R _ S O U R C E >------------------------
    --[[--------------------------< S E L E C T _ A U T H O R _ E D I T O R _ S O U R C E >------------------------


    Select one of |authors=, |authorn= / |lastn / firstn=, or |vauthors= as the source of the author name list or
    Select one of |authors=, |authorn= / |lastn / firstn=, or |vauthors= as the source of the author name list or
    select one of |editors=, |editorn= / editor-lastn= / |editor-firstn= or |veditors= as the source of the editor name list.
    select one of |editorn= / editor-lastn= / |editor-firstn= or |veditors= as the source of the editor name list.


    Only one of these appropriate three will be used.  The hierarchy is: |authorn= (and aliases) highest and |authors= lowest and
    Only one of these appropriate three will be used.  The hierarchy is: |authorn= (and aliases) highest and |authors= lowest;
    similarly, |editorn= (and aliases) highest and |editors= lowest
    |editorn= (and aliases) highest and |veditors= lowest (support for |editors= withdrawn)


    When looking for |authorn= / |editorn= parameters, test |xxxxor1= and |xxxxor2= (and all of their aliases); stops after the second
    When looking for |authorn= / |editorn= parameters, test |xxxxor1= and |xxxxor2= (and all of their aliases); stops after the second
    Line 2,113: Line 2,006:
    Emits an error message when more than one xxxxor name source is provided.
    Emits an error message when more than one xxxxor name source is provided.


    In this function, vxxxxors = vauthors or veditors; xxxxors = authors or editors as appropriate.
    In this function, vxxxxors = vauthors or veditors; xxxxors = authors as appropriate.


    ]]
    ]]


    local function select_author_editor_source (vxxxxors, xxxxors, args, list_name)
    local function select_author_editor_source (vxxxxors, xxxxors, args, list_name)
    local lastfirst = false;
    local lastfirst = false;
    if select_one( args, cfg.aliases[list_name .. '-Last'], 'redundant_parameters', 1 ) or -- do this twice incase we have a first 1 without a last1
    if utilities.select_one ( args, cfg.aliases[list_name .. '-Last'], 'none', 1 ) or -- do this twice in case we have a |first1= without a |last1=; this ...
    select_one( args, cfg.aliases[list_name .. '-Last'], 'redundant_parameters', 2 ) then
    utilities.select_one ( args, cfg.aliases[list_name .. '-First'], 'none', 1 ) or -- ... also catches the case where |first= is used with |vauthors=
    lastfirst=true;
    utilities.select_one ( args, cfg.aliases[list_name .. '-Last'], 'none', 2 ) or
    utilities.select_one ( args, cfg.aliases[list_name .. '-First'], 'none', 2 ) then
    lastfirst = true;
    end
    end


    if (is_set (vxxxxors) and true == lastfirst) or -- these are the three error conditions
    if (utilities.is_set (vxxxxors) and true == lastfirst) or -- these are the three error conditions
    (is_set (vxxxxors) and is_set (xxxxors)) or
    (utilities.is_set (vxxxxors) and utilities.is_set (xxxxors)) or
    (true == lastfirst and is_set (xxxxors)) then
    (true == lastfirst and utilities.is_set (xxxxors)) then
    local err_name;
    local err_name;
    if 'AuthorList' == list_name then -- figure out which name should be used in error message
    if 'AuthorList' == list_name then -- figure out which name should be used in error message
    Line 2,133: Line 2,028:
    err_name = 'editor';
    err_name = 'editor';
    end
    end
    table.insert( z.message_tail, { set_error( 'redundant_parameters',
    table.insert( z.message_tail, { utilities.set_message ( 'err_redundant_parameters',
    {err_name .. '-name-list parameters'}, true ) } ); -- add error message
    {err_name .. '-name-list parameters'}, true ) } ); -- add error message
    end
    end


    if true == lastfirst then return 1 end; -- return a number indicating which author name source to use
    if true == lastfirst then return 1 end; -- return a number indicating which author name source to use
    if is_set (vxxxxors) then return 2 end;
    if utilities.is_set (vxxxxors) then return 2 end;
    if is_set (xxxxors) then return 3 end;
    if utilities.is_set (xxxxors) then return 3 end;
    return 1; -- no authors so return 1; this allows missing author name test to run in case there is a first without last  
    return 1; -- no authors so return 1; this allows missing author name test to run in case there is a first without last  
    end
    end
    Line 2,147: Line 2,042:


    This function is used to validate a parameter's assigned value for those parameters that have only a limited number
    This function is used to validate a parameter's assigned value for those parameters that have only a limited number
    of allowable values (yes, y, true, no, etc).  When the parameter value has not been assigned a value (missing or empty
    of allowable values (yes, y, true, live, dead, etc.).  When the parameter value has not been assigned a value (missing
    in the source template) the function refurns true.  If the parameter value is one of the list of allowed values returns
    or empty in the source template) the function returns the value specified by ret_val.  If the parameter value is one
    true; else, emits an error message and returns false.
    of the list of allowed values returns the translated value; else, emits an error message and returns the value
    specified by ret_val.


    ]]
    ]]


    local function is_valid_parameter_value (value, name, possible)
    local function is_valid_parameter_value (value, name, possible, ret_val)
    if not is_set (value) then
    if not utilities.is_set (value) then
    return true; -- an empty parameter is ok
    return ret_val; -- an empty parameter is ok
    elseif in_array(value:lower(), possible) then
    elseif utilities.in_array (value, possible) then
    return true;
    return cfg.keywords_xlate[value]; -- return translation of parameter keyword
    else
    else
    table.insert( z.message_tail, { set_error( 'invalid_param_val', {name, value}, true ) } ); -- not an allowed value so add error message
    table.insert( z.message_tail, { utilities.set_message ( 'err_invalid_param_val', {name, value}, true ) } ); -- not an allowed value so add error message
    return false
    return ret_val;
    end
    end
    end
    end




    --[[--------------------------< I S _ P A R A M E T E R _ E X T _ W I K I L I N K >----------------------------
    --[[--------------------------< T E R M I N A T E _ N A M E _ L I S T >----------------------------------------


    Return true if a parameter value has a string that begins and ends with square brackets [ and ] and the first
    This function terminates a name list (author, contributor, editor) with a separator character (sepc) and a space
    characters following the opening bracket obey the rules of a uri scheme (see check_url()).  The test will also find
    when the last character is not a sepc character or when the last three characters are not sepc followed by two
    external wikilinks that use protocol relative urls.
    closing square brackets (close of a wikilink).  When either of these is true, the name_list is terminated with a
    single space character.


    ]]
    ]]


    local function is_parameter_ext_wikilink (value)
    local function terminate_name_list (name_list, sepc)
    if value:match ("%[%a[%a%d%+%.%-]*:.*%]") or value:match ("%[//.*%]") then -- does the param value contain an external wikilink?
    if (string.sub (name_list, -3, -1) == sepc .. '. ') then -- if already properly terminated
    return true;
    return name_list; -- just return the name list
    elseif (string.sub (name_list, -1, -1) == sepc) or (string.sub (name_list, -3, -1) == sepc .. ']]') then -- if last name in list ends with sepc char
    return name_list .. " "; -- don't add another
    else
    else
    return false;
    return name_list .. sepc .. ' '; -- otherwise terminate the name list
    end
    end
    end
    end




    --[[-------------------------< C H E C K _ F O R _ U R L >-----------------------------------------------------
    --[[-------------------------< F O R M A T _ V O L U M E _ I S S U E >----------------------------------------


    loop through a list of parameters and their values.  Look at the value and if it has an external link, emit an error message.
    returns the concatenation of the formatted volume and issue parameters as a single string; or formatted volume
    or formatted issue, or an empty string if neither are set.


    ]]
    ]]
    local function format_volume_issue (volume, issue, cite_class, origin, sepc, lower)
    if not utilities.is_set (volume) and not utilities.is_set (issue) then
    return '';
    end
    if 'magazine' == cite_class or (utilities.in_array (cite_class, {'citation', 'map'}) and 'magazine' == origin) then
    if utilities.is_set (volume) and utilities.is_set (issue) then
    return wrap_msg ('vol-no', {sepc, hyphen_to_dash (volume), issue}, lower);
    elseif utilities.is_set (volume) then
    return wrap_msg ('vol', {sepc, hyphen_to_dash (volume)}, lower);
    else
    return wrap_msg ('issue', {sepc, issue}, lower);
    end
    end
    if 'podcast' == cite_class and utilities.is_set (issue) then
    return wrap_msg ('issue', {sepc, issue}, lower);
    end


    local function check_for_url (parameter_list)
    local vol = ''; -- here for all cites except magazine
    local error_message = '';
    for k, v in pairs (parameter_list) do -- for each parameter in the list
    if utilities.is_set (volume) then
    if is_parameter_ext_wikilink (v) then -- look at the value; if there is a url add an error message
    if volume:match ('^[MDCLXVI]+$') or volume:match ('^%d+$') then -- volume value is all digits or all uppercase Roman numerals
    if is_set(error_message) then -- once we've added the first portion of the error message ...
    vol = utilities.substitute (cfg.presentation['vol-bold'], {sepc, volume}); -- render in bold face
    error_message=error_message .. ", "; -- ... add a comma space separator
    elseif (4 < mw.ustring.len(volume)) then -- not all digits or Roman numerals and longer than 4 characters
    end
    vol = utilities.substitute (cfg.messages['j-vol'], {sepc, hyphen_to_dash (volume)}); -- not bold
    error_message=error_message .. "&#124;" .. k .. "="; -- add the failed parameter
    utilities.add_prop_cat ('long_vol');
    else -- four or less characters
    vol = utilities.substitute (cfg.presentation['vol-bold'], {sepc, hyphen_to_dash (volume)}); -- bold
    end
    end
    end
    end
    if is_set (error_message) then -- done looping, if there is an error message, display it
    if utilities.is_set (issue) then
    table.insert( z.message_tail, { set_error( 'param_has_ext_link', {error_message}, true ) } );
    return vol .. utilities.substitute (cfg.messages['j-issue'], issue);
    end
    end
    return vol;
    end
    end




    --[[--------------------------< C I T A T I O N 0 >------------------------------------------------------------
    --[[-------------------------< F O R M A T _ P A G E S _ S H E E T S >-----------------------------------------


    This is the main function doing the majority of the citation formatting.
    adds static text to one of |page(s)= or |sheet(s)= values and returns it with all of the others set to empty strings.
    The return order is:
    page, pages, sheet, sheets
     
    Singular has priority over plural when both are provided.


    ]]
    ]]


    local function citation0( config, args)
    local function format_pages_sheets (page, pages, sheet, sheets, cite_class, origin, sepc, nopp, lower)
    --[[
    if 'map' == cite_class then -- only cite map supports sheet(s) as in-source locators
    Load Input Parameters
    if utilities.is_set (sheet) then
    The argument_wrapper facilitates the mapping of multiple aliases to single internal variable.
    if 'journal' == origin then
    ]]
    return '', '', wrap_msg ('j-sheet', sheet, lower), '';
    local A = argument_wrapper( args );
    else
    return '', '', wrap_msg ('sheet', {sepc, sheet}, lower), '';
    end
    elseif utilities.is_set (sheets) then
    if 'journal' == origin then
    return '', '', '', wrap_msg ('j-sheets', sheets, lower);
    else
    return '', '', '', wrap_msg ('sheets', {sepc, sheets}, lower);
    end
    end
    end


    local i
    local is_journal = 'journal' == cite_class or (utilities.in_array (cite_class, {'citation', 'map', 'interview'}) and 'journal' == origin);
    local PPrefix = A['PPrefix']
    local PPPrefix = A['PPPrefix']
    if utilities.is_set (page) then
    local NoPP = A['NoPP']  
    if is_journal then
    if is_valid_parameter_value (NoPP, 'nopp', cfg.keywords ['yes_true_y']) then
    return utilities.substitute (cfg.messages['j-page(s)'], page), '', '', '';
    PPPrefix = ''; -- unset these, prefix if used is in |page= or |pages=
    elseif not nopp then
    PPrefix = '';
    return utilities.substitute (cfg.messages['p-prefix'], {sepc, page}), '', '', '';
    else
    else
    NoPP = nil; -- unset, used as a flag later
    return utilities.substitute (cfg.messages['nopp'], {sepc, page}), '', '', '';
    end
    elseif utilities.is_set (pages) then
    if is_journal then
    return utilities.substitute (cfg.messages['j-page(s)'], pages), '', '', '';
    elseif tonumber(pages) ~= nil and not nopp then -- if pages is only digits, assume a single page number
    return '', utilities.substitute (cfg.messages['p-prefix'], {sepc, pages}), '', '';
    elseif not nopp then
    return '', utilities.substitute (cfg.messages['pp-prefix'], {sepc, pages}), '', '';
    else
    return '', utilities.substitute (cfg.messages['nopp'], {sepc, pages}), '', '';
    end
    end
    end
    -- Pick out the relevant fields from the arguments.  Different citation templates
    return '', '', '', ''; -- return empty strings
    -- define different field names for the same underlying things.
    end
    local author_etal;
    local a = {}; -- authors list from |lastn= / |firstn= pairs or |vauthors=
    local Authors;
    local NameListFormat = A['NameListFormat'];


    do -- to limit scope of selected
    local selected = select_author_editor_source (A['Vauthors'], A['Authors'], args, 'AuthorList');
    if 1 == selected then
    a, author_etal = extract_names (args, 'AuthorList'); -- fetch author list from |authorn= / |lastn= / |firstn=, |author-linkn=, and |author-maskn=
    elseif 2 == selected then
    NameListFormat = 'vanc'; -- override whatever |name-list-format= might be
    a, author_etal = parse_vauthors_veditors (args, args.vauthors, 'AuthorList'); -- fetch author list from |vauthors=, |author-linkn=, and |author-maskn=
    elseif 3 == selected then
    Authors = A['Authors']; -- use content of |authors=
    end
    end


    local Coauthors = A['Coauthors'];
    --[[--------------------------< I N S O U R C E _ L O C _ G E T >----------------------------------------------
    local Others = A['Others'];
     
    returns one of the in-source locators: page, pages, or at.
     
    If any of these are interwiki links to Wikisource, returns the label portion of the interwiki-link as plain text
    for use in COinS.  This COinS thing is done because here we convert an interwiki-link to an external link and
    add an icon span around that; get_coins_pages() doesn't know about the span.  TODO: should it? 
     
    TODO: add support for sheet and sheets?; streamline;
     
    TODO: make it so that this function returns only one of the three as the single in-source (the return value assigned
    to a new name)?
     
    ]]


    local editor_etal;
    local function insource_loc_get (page, page_orig, pages, pages_orig, at)
    local e = {}; -- editors list from |editor-lastn= / |editor-firstn= pairs or |veditors=
    local ws_url, ws_label, coins_pages, L; -- for Wikisource interwiki-links; TODO: this corrupts page metadata (span remains in place after cleanup; fix there?)
    local Editors;


    do -- to limit scope of selected
    if utilities.is_set (page) then
    local selected = select_author_editor_source (A['Veditors'], A['Editors'], args, 'EditorList');
    if utilities.is_set (pages) or utilities.is_set (at) then
    if 1 == selected then
    pages = ''; -- unset the others
    e, editor_etal = extract_names (args, 'EditorList'); -- fetch editor list from |editorn= / |editor-lastn= / |editor-firstn=, |editor-linkn=, and |editor-maskn=
    at = '';
    elseif 2 == selected then
    NameListFormat = 'vanc'; -- override whatever |name-list-format= might be
    e, editor_etal = parse_vauthors_veditors (args, args.veditors, 'EditorList'); -- fetch editor list from |veditors=, |editor-linkn=, and |editor-maskn=
    elseif 3 == selected then
    Editors = A['Editors']; -- use content of |editors=
    end
    end
    end
    extra_text_in_page_check (page, page_orig); -- emit error message when |page= value begins with what looks like p., pp., etc.


    local t = {}; -- translators list from |translator-lastn= / translator-firstn= pairs
    ws_url, ws_label, L = wikisource_url_make (page); -- make ws URL from |page= interwiki link; link portion L becomes tooltip label
    local Translators; -- assembled trnaslators name list
    if ws_url then
    t = extract_names (args, 'TranslatorList'); -- fetch translator list from |translatorn= / |translator-lastn=, -firstn=, -linkn=, -maskn=
    page = external_link (ws_url, ws_label .. '&nbsp;', 'ws link in page'); -- space char after label to move icon away from in-source text; TODO: a better way to do this?
    page = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, page});
    if not is_valid_parameter_value (NameListFormat, 'name-list-format', cfg.keywords['name-list-format']) then -- only accepted value for this parameter is 'vanc'
    coins_pages = ws_label;
    NameListFormat = ''; -- anything else, set to empty string
    end
    elseif utilities.is_set (pages) then
    if utilities.is_set (at) then
    at = ''; -- unset
    end
    extra_text_in_page_check (pages, pages_orig); -- emit error message when |page= value begins with what looks like p., pp., etc.
     
    ws_url, ws_label, L = wikisource_url_make (pages); -- make ws URL from |pages= interwiki link; link portion L becomes tooltip label
    if ws_url then
    pages = external_link (ws_url, ws_label .. '&nbsp;', 'ws link in pages'); -- space char after label to move icon away from in-source text; TODO: a better way to do this?
    pages = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, pages});
    coins_pages = ws_label;
    end
    elseif utilities.is_set (at) then
    ws_url, ws_label, L = wikisource_url_make (at); -- make ws URL from |at= interwiki link; link portion L becomes tooltip label
    if ws_url then
    at = external_link (ws_url, ws_label .. '&nbsp;', 'ws link in at'); -- space char after label to move icon away from in-source text; TODO: a better way to do this?
    at = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, at});
    coins_pages = ws_label;
    end
    end
    end
    return page, pages, at, coins_pages;
    end


    local Year = A['Year'];
    --[[--------------------------< I S _ U N I Q U E _ A R C H I V E _ U R L >------------------------------------
    local PublicationDate = A['PublicationDate'];
    local OrigYear = A['OrigYear'];
    local Date = A['Date'];
    local LayDate = A['LayDate'];
    ------------------------------------------------- Get title data
    local Title = A['Title'];
    local ScriptTitle = A['ScriptTitle'];
    local BookTitle = A['BookTitle'];
    local Conference = A['Conference'];
    local TransTitle = A['TransTitle'];
    local TitleNote = A['TitleNote'];
    local TitleLink = A['TitleLink'];
    local Chapter = A['Chapter'];
    local ScriptChapter = A['ScriptChapter'];
    local ChapterLink -- = A['ChapterLink']; -- deprecated as a parameter but still used internally by cite episode
    local TransChapter = A['TransChapter'];
    local TitleType = A['TitleType'];
    local Degree = A['Degree'];
    local Docket = A['Docket'];
    local ArchiveFormat = A['ArchiveFormat'];
    local ArchiveURL = A['ArchiveURL'];
    local URL = A['URL']
    local URLorigin = A:ORIGIN('URL'); -- get name of parameter that holds URL
    local ChapterURL = A['ChapterURL'];
    local ChapterURLorigin = A:ORIGIN('ChapterURL'); -- get name of parameter that holds ChapterURL
    local ConferenceFormat = A['ConferenceFormat'];
    local ConferenceURL = A['ConferenceURL'];
    local ConferenceURLorigin = A:ORIGIN('ConferenceURL'); -- get name of parameter that holds ConferenceURL
    local Periodical = A['Periodical'];


    local Series = A['Series'];
    add error message when |archive-url= value is same as |url= or chapter-url= (or alias...) value
    local Volume = A['Volume'];
    local Issue = A['Issue'];
    local Position = '';
    local Page = A['Page'];
    local Pages = hyphen_to_dash( A['Pages'] );
    local At = A['At'];


    local Edition = A['Edition'];
    ]]
    local PublicationPlace = A['PublicationPlace']
     
    local Place = A['Place'];
    local function is_unique_archive_url (archive, url, c_url, source, date)
    if utilities.is_set (archive) then
    local PublisherName = A['PublisherName'];
    if archive == url or archive == c_url then
    local RegistrationRequired = A['RegistrationRequired'];
    table.insert (z.message_tail, {utilities.set_message ('err_bad_url', {utilities.wrap_style ('parameter', source)}, true)}); -- add error message
    if not is_valid_parameter_value (RegistrationRequired, 'registration', cfg.keywords ['yes_true_y']) then
    return '', ''; -- unset |archive-url= and |archive-date= because same as |url= or |chapter-url=
    registration=nil;
    end
    local SubscriptionRequired = A['SubscriptionRequired'];
    if not is_valid_parameter_value (SubscriptionRequired, 'subscription', cfg.keywords ['yes_true_y']) then
    subscription=nil;
    end
    end
    end


    local Via = A['Via'];
    return archive, date;
    local AccessDate = A['AccessDate'];
    end
    local ArchiveDate = A['ArchiveDate'];
    local Agency = A['Agency'];
    local DeadURL = A['DeadURL']
    if not is_valid_parameter_value (DeadURL, 'dead-url', cfg.keywords ['deadurl']) then -- set in config.defaults to 'yes'
    DeadURL = ''; -- anything else, set to empty string
    end


    local Language = A['Language'];
    local Format = A['Format'];
    local ChapterFormat = A['ChapterFormat'];
    local DoiBroken = A['DoiBroken'];
    local ID = A['ID'];
    local ASINTLD = A['ASINTLD'];
    local IgnoreISBN = A['IgnoreISBN'];
    if not is_valid_parameter_value (IgnoreISBN, 'ignore-isbn-error', cfg.keywords ['yes_true_y']) then
    IgnoreISBN = nil; -- anything else, set to empty string
    end
    local Embargo = A['Embargo'];
    local Class = A['Class']; -- arxiv class identifier


    local ID_list = extract_ids( args );
    --[=[-------------------------< A R C H I V E _ U R L _ C H E C K >--------------------------------------------


    local Quote = A['Quote'];
    Check archive.org URLs to make sure they at least look like they are pointing at valid archives and not to the
    save snapshot URL or to calendar pages.  When the archive URL is 'https://web.archive.org/save/' (or http://...)
    archive.org saves a snapshot of the target page in the URL.  That is something that Wikipedia should not allow
    unwitting readers to do.


    local LayFormat = A['LayFormat'];
    When the archive.org URL does not have a complete timestamp, archive.org chooses a snapshot according to its own
    local LayURL = A['LayURL'];
    algorithm or provides a calendar 'search' result.  [[WP:ELNO]] discourages links to search results.
    local LaySource = A['LaySource'];
    local Transcript = A['Transcript'];
    local TranscriptFormat = A['TranscriptFormat'];
    local TranscriptURL = A['TranscriptURL']
    local TranscriptURLorigin = A:ORIGIN('TranscriptURL'); -- get name of parameter that holds TranscriptURL


    local LastAuthorAmp = A['LastAuthorAmp'];
    This function looks at the value assigned to |archive-url= and returns empty strings for |archive-url= and
    if not is_valid_parameter_value (LastAuthorAmp, 'last-author-amp', cfg.keywords ['yes_true_y']) then
    |archive-date= and an error message when:
    LastAuthorAmp = nil; -- set to empty string
    |archive-url= holds an archive.org save command URL
    end
    |archive-url= is an archive.org URL that does not have a complete timestamp (YYYYMMDDhhmmss 14 digits) in the
    local no_tracking_cats = A['NoTracking'];
    correct place
    if not is_valid_parameter_value (no_tracking_cats, 'no-tracking', cfg.keywords ['yes_true_y']) then
    otherwise returns |archive-url= and |archive-date=
    no_tracking_cats = nil; -- set to empty string
    end


    --these are used by cite interview
    There are two mostly compatible archive.org URLs:
    local Callsign = A['Callsign'];
    //web.archive.org/<timestamp>... -- the old form
    local City = A['City'];
    //web.archive.org/web/<timestamp>... -- the new form
    local Program = A['Program'];


    --local variables that are not cs1 parameters
    The old form does not support or map to the new form when it contains a display flag.  There are four identified flags
    local use_lowercase; -- controls capitalization of certain static text
    ('id_', 'js_', 'cs_', 'im_') but since archive.org ignores others following the same form (two letters and an underscore)
    local this_page = mw.title.getCurrentTitle(); -- also used for COinS and for language
    we don't check for these specific flags but we do check the form.
    local anchor_year; -- used in the CITEREF identifier
    local COinS_date; -- used in the COinS metadata


    -- set default parameter values defined by |mode= parameter.  If |mode= is empty or omitted, use CitationClass to set these values
    This function supports a preview mode.  When the article is rendered in preview mode, this function may return a modified
    local Mode = A['Mode'];
    archive URL:
    if not is_valid_parameter_value (Mode, 'mode', cfg.keywords['mode']) then
    for save command errors, return undated wildcard (/*/)
    Mode = '';
    for timestamp errors when the timestamp has a wildcard, return the URL unmodified
    end
    for timestamp errors when the timestamp does not have a wildcard, return with timestamp limited to six digits plus wildcard (/yyyymm*/)
    local sepc; -- separator between citation elements for CS1 a period, for CS2, a comma
    local PostScript;
    local Ref;
    sepc, PostScript, Ref = set_style (Mode:lower(), A['PostScript'], A['Ref'], config.CitationClass);
    use_lowercase = ( sepc == ',' ); -- used to control capitalization for certain static text


    --check this page to see if it is in one of the namespaces that cs1 is not supposed to add to the error categories
    ]=]
    if not is_set (no_tracking_cats) then -- ignore if we are already not going to categorize this page
     
    if in_array (this_page.nsText, cfg.uncategorized_namespaces) then
    local function archive_url_check (url, date)
    no_tracking_cats = "true"; -- set no_tracking_cats
    local err_msg = ''; -- start with the error message empty
    end
    local path, timestamp, flag; -- portions of the archive.org URL
    for _,v in ipairs (cfg.uncategorized_subpages) do -- cycle through page name patterns
    if this_page.text:match (v) then -- test page name against each pattern
    if (not url:match('//web%.archive%.org/')) and (not url:match('//liveweb%.archive%.org/')) then -- also deprecated liveweb Wayback machine URL
    no_tracking_cats = "true"; -- set no_tracking_cats
    return url, date; -- not an archive.org archive, return ArchiveURL and ArchiveDate
    break; -- bail out if one is found
    end
     
    if url:match('//web%.archive%.org/save/') then -- if a save command URL, we don't want to allow saving of the target page  
    err_msg = cfg.err_msg_supl.save;
    url = url:gsub ('(//web%.archive%.org)/save/', '%1/*/', 1); -- for preview mode: modify ArchiveURL
    elseif url:match('//liveweb%.archive%.org/') then
    err_msg = cfg.err_msg_supl.liveweb;
    else
    path, timestamp, flag = url:match('//web%.archive%.org/([^%d]*)(%d+)([^/]*)/'); -- split out some of the URL parts for evaluation
    if not utilities.is_set (timestamp) or 14 ~= timestamp:len() then -- path and flag optional, must have 14-digit timestamp here
    err_msg = cfg.err_msg_supl.timestamp;
    if '*' ~= flag then
    url=url:gsub ('(//web%.archive%.org/[^%d]*%d?%d?%d?%d?%d?%d?)[^/]*', '%1*', 1) -- for preview, modify ts to be yearmo* max (0-6 digits plus splat)
    end
    end
    elseif utilities.is_set (path) and 'web/' ~= path then -- older archive URLs do not have the extra 'web/' path element
    err_msg = cfg.err_msg_supl.path;
    elseif utilities.is_set (flag) and not utilities.is_set (path) then -- flag not allowed with the old form URL (without the 'web/' path element)
    err_msg = cfg.err_msg_supl.flag;
    elseif utilities.is_set (flag) and not flag:match ('%a%a_') then -- flag if present must be two alpha characters and underscore (requires 'web/' path element)
    err_msg = cfg.err_msg_supl.flag;
    else
    return url, date; -- return ArchiveURL and ArchiveDate
    end
    end
    end
    end
    -- if here, something not right so
    table.insert( z.message_tail, { utilities.set_message ( 'err_archive_url', {err_msg}, true ) } ); -- add error message and
    if utilities.is_set (Frame:preprocess('{{REVISIONID}}')) then
    return '', ''; -- return empty strings for ArchiveURL and ArchiveDate
    else
    return url, date; -- preview mode so return ArchiveURL and ArchiveDate
    end
    end
    --[[--------------------------< P L A C E _ C H E C K >--------------------------------------------------------


    -- check for extra |page=, |pages= or |at= parameters.
    check |place=, |publication-place=, |location= to see if these params include digits. This function added because
    if is_set(Page) then
    many editors misuse location to specify the in-source location (|page(s)= and |at= are supposed to do that)
    if is_set(Pages) or is_set(At) then
     
    Page = Page .. " " .. set_error('extra_pages'); -- add error message
    returns the original parameter value without modification; added maint cat when parameter value contains digits
    Pages = ''; -- unset the others
     
    At = '';
    ]]
    end
    extra_text_in_page_check (Page, NoPP); -- add this page to maint cat if |page= value begins with what looks like p. or pp.
    elseif is_set(Pages) then
    if is_set(At) then
    Pages = Pages .. " " .. set_error('extra_pages'); -- add error messages
    At = ''; -- unset
    end
    extra_text_in_page_check (Pages, NoPP); -- add this page to maint cat if |page= value begins with what looks like p. or pp.
    end


    -- both |publication-place= and |place= (|location=) allowed if different
    local function place_check (param_val)
    if not is_set(PublicationPlace) and is_set(Place) then
    if not utilities.is_set (param_val) then -- parameter empty or omitted
    PublicationPlace = Place; -- promote |place= (|location=) to |publication-place
    return param_val; -- return that empty state
    end
    end
    if PublicationPlace == Place then Place = ''; end -- don't need both if they are the same
    if mw.ustring.find (param_val, '%d') then -- not empty, are there digits in the parameter value
    utilities.set_message ('maint_location'); -- yep, add maint cat
    end
    --[[
    return param_val; -- and done
    Parameter remapping for cite encyclopedia:
    end
    When the citation has these parameters:
    |encyclopedia and |title then map |title to |article and |encyclopedia to |title
    |encyclopedia and |article then map |encyclopedia to |title
    |encyclopedia then map |encyclopedia to |title


    |trans_title maps to |trans_chapter when |title is re-mapped
    |url maps to |chapterurl when |title is remapped


    All other combinations of |encyclopedia, |title, and |article are not modified
    --[[--------------------------< I S _ G E N E R I C _ T I T L E >----------------------------------------------
     
    compares |title= value against list of known generic title patterns.  Returns true when pattern matches; nil else
     
    the k/v pairs in 'generic_titles' each contain two tables, one for English and one for another 'local' language
    Each of those tables contain another table that holds the string or pattern (whole title or title fragment) in
    index [1].  index [2] is a Boolean that tells string.find() or mw.ustring.find() to do plain-text search (true)
    or a pattern search (false).  The intent of all this complexity is to make these searches as fast as possible so
    that we don't run out of processing time on very large articles.


    ]]
    ]]


    local Encyclopedia = A['Encyclopedia'];
    local function is_generic_title (title)
     
    title = mw.ustring.lower(title); -- switch title to lower case
    if ( config.CitationClass == "encyclopaedia" ) or ( config.CitationClass == "citation" and is_set (Encyclopedia)) then -- test code for citation
    for _, generic_title in ipairs (cfg.special_case_translation['generic_titles']) do -- spin through the list of known generic title fragments
    if is_set(Periodical) then -- Periodical is set when |encyclopedia is set
    if title:find (generic_title['en'][1], 1, generic_title['en'][2]) then
    if is_set(Title) or is_set (ScriptTitle) then
    return true; -- found English generic title so done
    if not is_set(Chapter) then
    elseif generic_title['local'] then -- to keep work load down, generic_title['local'] should be nil except when there is a local version of the generic title
    Chapter = Title; -- |encyclopedia and |title are set so map |title to |article and |encyclopedia to |title
    if mw.ustring.find (title, generic_title['local'][1], 1, generic_title['local'][2]) then -- mw.ustring() because might not be Latin script
    ScriptChapter = ScriptTitle;
    return true; -- found local generic title so done
    TransChapter = TransTitle;
    ChapterURL = URL;
    if not is_set (ChapterURL) and is_set (TitleLink) then
    Chapter= '[[' .. TitleLink .. '|' .. Chapter .. ']]';
    end
    Title = Periodical;
    ChapterFormat = Format;
    Periodical = ''; -- redundant so unset
    TransTitle = '';
    URL = '';
    Format = '';
    TitleLink = '';
    ScriptTitle = '';
    end
    else -- |title not set
    Title = Periodical; -- |encyclopedia set and |article set or not set so map |encyclopedia to |title
    Periodical = ''; -- redundant so unset
    end
    end
    end
    end
    end
    end
    end


    -- Special case for cite techreport.
    if (config.CitationClass == "techreport") then -- special case for cite techreport
    if is_set(Issue) then -- cite techreport uses 'number', which other citations aliase to 'issue'
    if not is_set(ID) then -- can we use ID for the "number"?
    ID = Issue; -- yes, use it
    Issue = ""; -- unset Issue so that "number" isn't duplicated in the rendered citation or COinS metadata
    else -- can't use ID so emit error message
    ID = ID .. " " .. set_error('redundant_parameters', '<code>&#124;id=</code> and <code>&#124;number=</code>');
    end
    end
    end


    -- special case for cite interview
    --[[--------------------------< I S _ A R C H I V E D _ C O P Y >----------------------------------------------
    if (config.CitationClass == "interview") then
     
    if is_set(Program) then
    compares |title= to 'Archived copy' (placeholder added by bots that can't find proper title); if matches, return true; nil else
    ID = ' ' .. Program;
     
    end
    ]]
    if is_set(Callsign) then
     
    if is_set(ID) then
    local function is_archived_copy (title)
    ID = ID .. sepc .. ' ' .. Callsign;
    title = mw.ustring.lower(title); -- switch title to lower case
    else
    if title:find (cfg.special_case_translation.archived_copy.en) then -- if title is 'Archived copy'
    ID = ' ' .. Callsign;
    return true;
    end
    elseif cfg.special_case_translation.archived_copy['local'] then
    end
    if mw.ustring.find (title, cfg.special_case_translation.archived_copy['local']) then -- mw.ustring() because might not be Latin script
    if is_set(City) then
    return true;
    if is_set(ID) then
    ID = ID .. sepc .. ' ' .. City;
    else
    ID = ' ' .. City;
    end
    end
    end
    end
    end


    if is_set(Others) then
    --[[--------------------------< C I T A T I O N 0 >------------------------------------------------------------
    if is_set(TitleType) then
    Others = ' ' .. TitleType .. ' with ' .. Others;
    TitleType = '';
    else
    Others = ' ' .. 'Interview with ' .. Others;
    end
    else
    Others = '(Interview)';
    end
    end


    -- special case for cite mailing list
    This is the main function doing the majority of the citation formatting.
    if (config.CitationClass == "mailinglist") then
    Periodical = A ['MailingList'];
    end


    -- Account for the oddity that is {{cite conference}}, before generation of COinS data.
    ]]
    if 'conference' == config.CitationClass then
    if is_set(BookTitle) then
    Chapter = Title;
    -- ChapterLink = TitleLink; -- |chapterlink= is deprecated
    ChapterURL = URL;
    ChapterURLorigin = URLorigin;
    URLorigin = '';
    ChapterFormat = Format;
    TransChapter = TransTitle;
    Title = BookTitle;
    Format = '';
    -- TitleLink = '';
    TransTitle = '';
    URL = '';
    end
    elseif 'speech' ~= config.CitationClass then
    Conference = ''; -- not cite conference or cite speech so make sure this is empty string
    end


    -- cite map oddities
    local function citation0( config, args )
    local Cartography = "";
    --[[  
    local Scale = "";
    Load Input Parameters
    local Sheet = A['Sheet'] or '';
    The argument_wrapper facilitates the mapping of multiple aliases to single internal variable.
    local Sheets = A['Sheets'] or '';
    ]]
    if config.CitationClass == "map" then
    local A = argument_wrapper ( args );
    Chapter = A['Map'];
    local i
    ChapterURL = A['MapURL'];
    TransChapter = A['TransMap'];
    ChapterURLorigin = A:ORIGIN('MapURL');
    ChapterFormat = A['MapFormat'];
    Cartography = A['Cartography'];
    if is_set( Cartography ) then
    Cartography = sepc .. " " .. wrap_msg ('cartography', Cartography, use_lowercase);
    end
    Scale = A['Scale'];
    if is_set( Scale ) then
    Scale = sepc .. " " .. Scale;
    end
    end


    -- Account for the oddities that are {{cite episode}} and {{cite serial}}, before generation of COinS data.
    -- Pick out the relevant fields from the arguments. Different citation templates
    if 'episode' == config.CitationClass or 'serial' == config.CitationClass then
    -- define different field names for the same underlying things.
    local AirDate = A['AirDate'];
    local SeriesLink = A['SeriesLink'];
    local Network = A['Network'];
    local Station = A['Station'];
    local s, n = {}, {};


    -- do common parameters first
    local author_etal;
    if is_set(Network) then table.insert(n, Network); end
    local a = {}; -- authors list from |lastn= / |firstn= pairs or |vauthors=
    if is_set(Station) then table.insert(n, Station); end
    local Authors;
    ID = table.concat(n, sepc .. ' ');
    local NameListStyle = is_valid_parameter_value (A['NameListStyle'], A:ORIGIN('NameListStyle'), cfg.keywords_lists['name-list-style'], '');
    local Collaboration = A['Collaboration'];
    if not is_set (Date) then -- promote airdate or Began/Ended to date
     
    if is_set (AirDate) then
    do -- to limit scope of selected
    Date = AirDate;
    local selected = select_author_editor_source (A['Vauthors'], A['Authors'], args, 'AuthorList');
    if 1 == selected then
    a, author_etal = extract_names (args, 'AuthorList'); -- fetch author list from |authorn= / |lastn= / |firstn=, |author-linkn=, and |author-maskn=
    elseif 2 == selected then
    NameListStyle = 'vanc'; -- override whatever |name-list-style= might be
    a, author_etal = parse_vauthors_veditors (args, args.vauthors, 'AuthorList'); -- fetch author list from |vauthors=, |author-linkn=, and |author-maskn=
    elseif 3 == selected then
    Authors = A['Authors']; -- use content of |authors=
    if 'authors' == A:ORIGIN('Authors') then -- but add a maint cat if the parameter is |authors=
    utilities.set_message ('maint_authors'); -- because use of this parameter is discouraged; what to do about the aliases is a TODO:
    end
    end
    end
    end
    if utilities.is_set (Collaboration) then
    author_etal = true; -- so that |display-authors=etal not required
    end
    end


    if 'episode' == config.CitationClass then -- handle the oddities that are strictly {{cite episode}}
    local editor_etal;
    local Season = A['Season'];
    local e = {}; -- editors list from |editor-lastn= / |editor-firstn= pairs or |veditors=
    local SeriesNumber = A['SeriesNumber'];


    if is_set (Season) and is_set (SeriesNumber) then -- these are mutually exclusive so if both are set
    do -- to limit scope of selected
    table.insert( z.message_tail, { set_error( 'redundant_parameters', {wrap_style ('parameter', 'season') .. ' and ' .. wrap_style ('parameter', 'seriesno')}, true ) } ); -- add error message
    local selected = select_author_editor_source (A['Veditors'], nil, args, 'EditorList'); -- support for |editors= withdrawn
    SeriesNumber = ''; -- unset; prefer |season= over |seriesno=
    if 1 == selected then
    e, editor_etal = extract_names (args, 'EditorList'); -- fetch editor list from |editorn= / |editor-lastn= / |editor-firstn=, |editor-linkn=, and |editor-maskn=
    elseif 2 == selected then
    NameListStyle = 'vanc'; -- override whatever |name-list-style= might be
    e, editor_etal = parse_vauthors_veditors (args, args.veditors, 'EditorList'); -- fetch editor list from |veditors=, |editor-linkn=, and |editor-maskn=
    end
    end
    local Chapter = A['Chapter']; -- done here so that we have access to |contribution= from |chapter= aliases
    local Chapter_origin = A:ORIGIN ('Chapter');
    local Contribution; -- because contribution is required for contributor(s)
    if 'contribution' == Chapter_origin then
    Contribution = Chapter; -- get the name of the contribution
    end
    local c = {}; -- contributors list from |contributor-lastn= / contributor-firstn= pairs
    if utilities.in_array (config.CitationClass, {"book", "citation"}) and not utilities.is_set (A['Periodical']) then -- |contributor= and |contribution= only supported in book cites
    c = extract_names (args, 'ContributorList'); -- fetch contributor list from |contributorn= / |contributor-lastn=, -firstn=, -linkn=, -maskn=
    if 0 < #c then
    if not utilities.is_set (Contribution) then -- |contributor= requires |contribution=
    table.insert( z.message_tail, { utilities.set_message ( 'err_contributor_missing_required_param', 'contribution')}); -- add missing contribution error message
    c = {}; -- blank the contributors' table; it is used as a flag later
    end
    end
    -- assemble a table of parts concatenated later into Series
    if 0 == #a then -- |contributor= requires |author=
    if is_set(Season) then table.insert(s, wrap_msg ('season', Season, use_lowercase)); end
    table.insert( z.message_tail, { utilities.set_message ( 'err_contributor_missing_required_param', 'author')}); -- add missing author error message
    if is_set(SeriesNumber) then table.insert(s, wrap_msg ('series', SeriesNumber, use_lowercase)); end
    c = {}; -- blank the contributors' table; it is used as a flag later
    if is_set(Issue) then table.insert(s, wrap_msg ('episode', Issue, use_lowercase)); end
    Issue = ''; -- unset because this is not a unique parameter
    Chapter = Title; -- promote title parameters to chapter
    ScriptChapter = ScriptTitle;
    ChapterLink = TitleLink; -- alias episodelink
    TransChapter = TransTitle;
    ChapterURL = URL;
    ChapterURLorigin = A:ORIGIN('URL');
    Title = Series; -- promote series to title
    TitleLink = SeriesLink;
    Series = table.concat(s, sepc .. ' '); -- this is concatenation of season, seriesno, episode number
     
    if is_set (ChapterLink) and not is_set (ChapterURL) then -- link but not URL
    Chapter = '[[' .. ChapterLink .. '|' .. Chapter .. ']]'; -- ok to wikilink
    elseif is_set (ChapterLink) and is_set (ChapterURL) then -- if both are set, URL links episode;
    Series = '[[' .. ChapterLink .. '|' .. Series .. ']]'; -- series links with ChapterLink (episodelink -> TitleLink -> ChapterLink) ugly
    end
    end
    URL = ''; -- unset
    TransTitle = '';
    ScriptTitle = '';
    else -- now oddities that are cite serial
    Issue = ''; -- unset because this parameter no longer supported by the citation/core version of cite serial
    Chapter = A['Episode']; -- TODO: make |episode= available to cite episode someday?
    if is_set (Series) and is_set (SeriesLink) then
    Series = '[[' .. SeriesLink .. '|' .. Series .. ']]';
    end
    Series = wrap_style ('italic-title', Series); -- series is italicized
    end
    end
    -- end of {{cite episode}} stuff
    -- Account for the oddities that are {{cite arxiv}}, before generation of COinS data.
    if 'arxiv' == config.CitationClass then
    if not is_set (ID_list['ARXIV']) then -- |arxiv= or |eprint= required for cite arxiv
    table.insert( z.message_tail, { set_error( 'arxiv_missing', {}, true ) } ); -- add error message
    elseif is_set (Series) then -- series is an alias of version
    ID_list['ARXIV'] = ID_list['ARXIV'] .. Series; -- concatenate version onto the end of the arxiv identifier
    Series = ''; -- unset
    deprecated_parameter ('version'); -- deprecated parameter but only for cite arxiv
    end
    end
    else -- if not a book cite
    if first_set (AccessDate, At, Chapter, Format, Page, Pages, Periodical, PublisherName, URL, -- a crude list of parameters that are not supported by cite arxiv
    if utilities.select_one (args, cfg.aliases['ContributorList-Last'], 'err_redundant_parameters', 1 ) then -- are there contributor name list parameters?
    ID_list['ASIN'], ID_list['BIBCODE'], ID_list['DOI'], ID_list['ISBN'], ID_list['ISSN'],
    table.insert( z.message_tail, { utilities.set_message ( 'err_contributor_ignored')}); -- add contributor ignored error message
    ID_list['JFM'], ID_list['JSTOR'], ID_list['LCCN'], ID_list['MR'], ID_list['OCLC'], ID_list['OL'],
    ID_list['OSTI'], ID_list['PMC'], ID_list['PMID'], ID_list['RFC'], ID_list['SSRN'], ID_list['USENETID'], ID_list['ZBL']) then
    table.insert( z.message_tail, { set_error( 'arxiv_params_not_supported', {}, true ) } ); -- add error message
     
    AccessDate= ''; -- set these to empty string; not supported in cite arXiv
    PublisherName = ''; -- (if the article has been published, use cite journal, or other)
    Chapter = '';
    URL = '';
    Format = '';
    Page = ''; Pages = ''; At = '';
    end
    end
    Periodical = 'arXiv'; -- set to arXiv for COinS; after that, must be set to empty string
    Contribution = nil; -- unset
    end
    end


    -- handle type parameter for those CS1 citations that have default values
    local Title = A['Title'];
    local TitleLink = A['TitleLink'];


    if in_array(config.CitationClass, {"AV-media-notes", "DVD-notes", "mailinglist", "map", "podcast", "pressrelease", "report", "techreport", "thesis"}) then
    local auto_select = ''; -- default is auto
    TitleType = set_titletype (config.CitationClass, TitleType);
    local accept_link;
    if is_set(Degree) and "Thesis" == TitleType then -- special case for cite thesis
    TitleLink, accept_link = utilities.has_accept_as_written(TitleLink, true); -- test for accept-this-as-written markup
    TitleType = Degree .. " thesis";
    if (not accept_link) and utilities.in_array (TitleLink, {'none', 'pmc', 'doi'}) then -- check for special keywords
    end
    auto_select = TitleLink; -- remember selection for later
    TitleLink = ''; -- treat as if |title-link= would have been empty
    end
    end


    if is_set(TitleType) then -- if type parameter is specified
    TitleLink = link_title_ok (TitleLink, A:ORIGIN ('TitleLink'), Title, 'title'); -- check for wiki-markup in |title-link= or wiki-markup in |title= when |title-link= is set
    TitleType = " (" .. TitleType .. ")"; -- display it in parentheses
     
    local Section = ''; -- {{cite map}} only; preset to empty string for concatenation if not used
    if 'map' == config.CitationClass and 'section' == Chapter_origin then
    Section = A['Chapter']; -- get |section= from |chapter= alias list; |chapter= and the other aliases not supported in {{cite map}}
    Chapter = ''; -- unset for now; will be reset later from |map= if present
    end
    end


    -- legacy: promote concatenation of |month=, and |year= to Date if Date not set; or, promote PublicationDate to Date if neither Date nor Year are set.
    local Periodical = A['Periodical'];
    if not is_set (Date) then
    local Periodical_origin = '';
    Date = Year; -- promote Year to Date
    if utilities.is_set (Periodical) then
    Year = nil; -- make nil so Year as empty string isn't used for CITEREF
    Periodical_origin = A:ORIGIN('Periodical'); -- get the name of the periodical parameter
    if not is_set (Date) and is_set(PublicationDate) then -- use PublicationDate when |date= and |year= are not set
    local i;
    Date = PublicationDate; -- promote PublicationDate to Date
    Periodical, i = utilities.strip_apostrophe_markup (Periodical); -- strip apostrophe markup so that metadata isn't contaminated
    PublicationDate = ''; -- unset, no longer needed
    if i then -- non-zero when markup was stripped so emit an error message
    table.insert( z.message_tail, {utilities.set_message ('err_apostrophe_markup', {Periodical_origin}, true)});
    end
    end
    end
    end


    if PublicationDate == Date then PublicationDate = ''; end -- if PublicationDate is same as Date, don't display in rendered citation
    if 'mailinglist' == config.CitationClass then -- special case for {{cite mailing list}}
    if utilities.is_set (Periodical) and utilities.is_set (A ['MailingList']) then -- both set emit an error
    table.insert( z.message_tail, {utilities.set_message ('err_redundant_parameters', {utilities.wrap_style ('parameter', Periodical_origin) .. ' and ' .. utilities.wrap_style ('parameter', 'mailinglist')}, true )});
    end


    --[[
    Periodical = A ['MailingList']; -- error or no, set Periodical to |mailinglist= value because this template is {{cite mailing list}}
    Go test all of the date-holding parameters for valid MOS:DATE format and make sure that dates are real dates. This must be done before we do COinS because here is where
    Periodical_origin = A:ORIGIN('MailingList');
    we get the date used in the metadata.
    end


    Date validation supporting code is in Module:Citation/CS1/Date_validation
    local ScriptPeriodical = A['ScriptPeriodical'];
    ]]
    do -- create defined block to contain local variables error_message and mismatch
    local error_message = '';
    -- AirDate has been promoted to Date so not necessary to check it
    anchor_year, COinS_date, error_message = dates({['access-date']=AccessDate, ['archive-date']=ArchiveDate, ['date']=Date, ['doi-broken-date']=DoiBroken,
    ['embargo']=Embargo, ['lay-date']=LayDate, ['publication-date']=PublicationDate, ['year']=Year});


    if is_set (Year) and is_set (Date) then -- both |date= and |year= not normally needed;  
    -- web and news not tested for now because of
    local mismatch = year_date_check (Year, Date)
    -- Wikipedia:Administrators%27_noticeboard#Is_there_a_semi-automated_tool_that_could_fix_these_annoying_"Cite_Web"_errors?
    if 0 == mismatch then -- |year= does not match a year-value in |date=
    if not (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) then -- 'periodical' templates require periodical parameter
    if is_set (error_message) then -- if there is already an error message
    -- local p = {['journal'] = 'journal', ['magazine'] = 'magazine', ['news'] = 'newspaper', ['web'] = 'website'}; -- for error message
    error_message = error_message .. ', '; -- tack on this additional message
    local p = {['journal'] = 'journal', ['magazine'] = 'magazine'}; -- for error message
    end
    if p[config.CitationClass]  then
    error_message = error_message .. '&#124;year= / &#124;date= mismatch';
    table.insert( z.message_tail, {utilities.set_message ('err_missing_periodical', {config.CitationClass, p[config.CitationClass]}, true)});
    elseif 1 == mismatch then -- |year= matches year-value in |date=
    end
    add_maint_cat ('date_year');
    end
    local Volume;
    local ScriptPeriodical_origin = A:ORIGIN('ScriptPeriodical');
    if 'citation' == config.CitationClass then
    if utilities.is_set (Periodical) then
    if not utilities.in_array (Periodical_origin, {'website', 'mailinglist'}) then -- {{citation}} does not render volume for these 'periodicals'
    Volume = A['Volume']; -- but does for all other 'periodicals'
    end
    elseif utilities.is_set (ScriptPeriodical) then
    if 'script-website' ~= ScriptPeriodical_origin then -- {{citation}} does not render volume for |script-website=
    Volume = A['Volume']; -- but does for all other 'periodicals'
    end
    end
    else
    Volume = A['Volume']; -- and does for non-'periodical' cites
    end
    end
    elseif utilities.in_array (config.CitationClass, cfg.templates_using_volume) then -- render |volume= for cs1 according to the configuration settings
    Volume = A['Volume'];
    end
    extra_text_in_vol_iss_check (Volume, A:ORIGIN ('Volume'), 'v');


    if is_set(error_message) then
    local Issue;
    table.insert( z.message_tail, { set_error( 'bad_date', {error_message}, true ) } ); -- add this error message
    if 'citation' == config.CitationClass then
    if utilities.is_set (Periodical) and utilities.in_array (Periodical_origin, {'journal', 'magazine', 'newspaper', 'periodical', 'work'}) or -- {{citation}} renders issue for these 'periodicals'
    utilities.is_set (ScriptPeriodical) and utilities.in_array (ScriptPeriodical_origin, {'script-journal', 'script-magazine', 'script-newspaper', 'script-periodical', 'script-work'}) then -- and these 'script-periodicals'
    Issue = hyphen_to_dash (A['Issue']);
    end
    end
    end -- end of do
    elseif utilities.in_array (config.CitationClass, cfg.templates_using_issue) then -- conference & map books do not support issue; {{citation}} listed here because included in settings table
     
    if not (utilities.in_array (config.CitationClass, {'conference', 'map', 'citation'}) and not (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical))) then
    -- Account for the oddity that is {{cite journal}} with |pmc= set and |url= not set.  Do this after date check but before COInS.
    Issue = hyphen_to_dash (A['Issue']);
    -- Here we unset Embargo if PMC not embargoed (|embargo= not set in the citation) or if the embargo time has expired. Otherwise, holds embargo date
    Embargo = is_embargoed (Embargo); --
     
    if config.CitationClass == "journal" and not is_set(URL) and is_set(ID_list['PMC']) then
    if not is_set (Embargo) then -- if not embargoed or embargo has expired
    URL=cfg.id_handlers['PMC'].prefix .. ID_list['PMC']; -- set url to be the same as the PMC external link if not embargoed
    URLorigin = cfg.id_handlers['PMC'].parameters[1]; -- set URLorigin to parameter name for use in error message if citation is missing a |title=
    end
    end
    end
    end
    extra_text_in_vol_iss_check (Issue, A:ORIGIN ('Issue'), 'i');


    -- At this point fields may be nil if they weren't specified in the template use.  We can use that fact.
    local Page;
    -- Test if citation has no title
    local Pages;
    if not is_set(Title) and
    local At;
    not is_set(TransTitle) and
    if not utilities.in_array (config.CitationClass, cfg.templates_not_using_page) then
    not is_set(ScriptTitle) then
    Page = A['Page'];
    if 'episode' == config.CitationClass then -- special case for cite episode; is there a better way to do this?
    Pages = hyphen_to_dash (A['Pages']);
    table.insert( z.message_tail, { set_error( 'citation_missing_title', {'series'}, true ) } );
    At = A['At'];
    else
    table.insert( z.message_tail, { set_error( 'citation_missing_title', {'title'}, true ) } );
    end
    end
    end
    local Edition = A['Edition'];
    local PublicationPlace = place_check (A['PublicationPlace'], A:ORIGIN('PublicationPlace'));
    local Place = place_check (A['Place'], A:ORIGIN('Place'));
    if 'none' == Title and is_set(Periodical) and not (( config.CitationClass == "encyclopaedia" ) or ( config.CitationClass == "citation" and is_set (Encyclopedia))) then -- special case
    local PublisherName = A['PublisherName'];
    Title = ''; -- set title to empty string
    local PublisherName_origin = A:ORIGIN('PublisherName');
    add_maint_cat ('untitled');
    if utilities.is_set (PublisherName) then
    local i = 0;
    PublisherName, i = utilities.strip_apostrophe_markup (PublisherName); -- strip apostrophe markup so that metadata isn't contaminated; publisher is never italicized
    if i then -- non-zero when markup was stripped so emit an error message
    table.insert( z.message_tail, {utilities.set_message ('err_apostrophe_markup', {PublisherName_origin}, true)});
    end
    end
    end


    check_for_url ({['title']=Title, ['chapter']=Chapter, ['work']=Periodical}); -- adds error message when any of these parameters contain a URL
    local Newsgroup = A['Newsgroup']; -- TODO: strip apostrophe markup?
    local Newsgroup_origin = A:ORIGIN('Newsgroup');


    -- COinS metadata (see <http://ocoins.info/>) for automated parsing of citation information.
    if 'newsgroup' == config.CitationClass then
    -- handle the oddity that is cite encyclopedia and {{citation |encyclopedia=something}}. Here we presume that
    if utilities.is_set (PublisherName) then -- general use parameter |publisher= not allowed in cite newsgroup
    -- when Periodical, Title, and Chapter are all set, then Periodical is the book (encyclopedia) title, Title
    local error_text, error_state = utilities.set_message ('err_parameter_ignored', {PublisherName_origin}, true);
    -- is the article title, and Chapter is a section within the article. So, we remap
    if utilities.is_set (error_text) then
    table.insert( z.message_tail, {error_text, error_state} );
    end
    end
     
    PublisherName = nil; -- ensure that this parameter is unset for the time being; will be used again after COinS
    end
     
    local URL = A['URL']
    local UrlAccess = is_valid_parameter_value (A['UrlAccess'], A:ORIGIN('UrlAccess'), cfg.keywords_lists['url-access'], nil);
    local coins_chapter = Chapter; -- default assuming that remapping not required
    if not utilities.is_set (URL) and utilities.is_set (UrlAccess) then
    local coins_title = Title; -- et tu
    UrlAccess = nil;
    if 'encyclopaedia' == config.CitationClass or ('citation' == config.CitationClass and is_set (Encyclopedia)) then
    table.insert( z.message_tail, { utilities.set_message ( 'err_param_access_requires_param', {'url'}, true ) } );
    if is_set (Chapter) and is_set (Title) and is_set (Periodical) then -- if all are used then
    coins_chapter = Title; -- remap
    coins_title = Periodical;
    end
    end
    end
    -- this is the function call to COinS()
    local ChapterURL = A['ChapterURL'];
    local OCinSoutput = COinS({
    local ChapterUrlAccess = is_valid_parameter_value (A['ChapterUrlAccess'], A:ORIGIN('ChapterUrlAccess'), cfg.keywords_lists['url-access'], nil);
    ['Periodical'] = Periodical,
    if not utilities.is_set (ChapterURL) and utilities.is_set (ChapterUrlAccess) then
    ['Chapter'] = make_coins_title (coins_chapter, ScriptChapter), -- Chapter and ScriptChapter stripped of bold / italic wikimarkup
    ChapterUrlAccess = nil;
    ['Title'] = make_coins_title (coins_title, ScriptTitle), -- Title and ScriptTitle stripped of bold / italic wikimarkup
    table.insert( z.message_tail, { utilities.set_message ( 'err_param_access_requires_param', {A:ORIGIN('ChapterUrlAccess'):gsub ('%-access', '')}, true ) } );
    ['PublicationPlace'] = PublicationPlace,
    ['Date'] = first_set(COinS_date, Date), -- COinS_date has correctly formatted date if Date is valid; any reason to keep Date here?  Should we be including invalid dates in metadata?
    ['Series'] = Series,
    ['Volume'] = Volume,
    ['Issue'] = Issue,
    ['Pages'] = get_coins_pages (first_set(Sheet, Sheets, Page, Pages, At)), -- pages stripped of external links
    ['Edition'] = Edition,
    ['PublisherName'] = PublisherName,
    ['URL'] = first_set( URL, ChapterURL ),
    ['Authors'] = a,
    ['ID_list'] = ID_list,
    ['RawPage'] = this_page.prefixedText,
    }, config.CitationClass);
     
    -- Account for the oddities that are {{cite arxiv}}, AFTER generation of COinS data.
    if 'arxiv' == config.CitationClass then -- we have set rft.jtitle in COinS to arXiv, now unset so it isn't displayed
    Periodical = ''; -- periodical not allowed in cite arxiv; if article has been published, use cite journal
    end
    end


    -- special case for cite newsgroup.  Do this after COinS because we are modifying Publishername to include some static text
    local MapUrlAccess = is_valid_parameter_value (A['MapUrlAccess'], A:ORIGIN('MapUrlAccess'), cfg.keywords_lists['url-access'], nil);
    if 'newsgroup' == config.CitationClass then
    if not utilities.is_set (A['MapURL']) and utilities.is_set (MapUrlAccess) then
    if is_set (PublisherName) then
    MapUrlAccess = nil;
    PublisherName = '[[Usenet newsgroup|Newsgroup]]:&nbsp;' .. external_link( 'news:' .. PublisherName, PublisherName );
    table.insert( z.message_tail, { utilities.set_message ( 'err_param_access_requires_param', {'map-url'}, true ) } );
    end
    end
    end


    local this_page = mw.title.getCurrentTitle(); -- also used for COinS and for language
    local no_tracking_cats = is_valid_parameter_value (A['NoTracking'], A:ORIGIN('NoTracking'), cfg.keywords_lists['yes_true_y'], nil);


     
    -- check this page to see if it is in one of the namespaces that cs1 is not supposed to add to the error categories
    -- Now perform various field substitutions.
    if not utilities.is_set (no_tracking_cats) then -- ignore if we are already not going to categorize this page
    -- We also add leading spaces and surrounding markup and punctuation to the
    if utilities.in_array (this_page.nsText, cfg.uncategorized_namespaces) then
    -- various parts of the citation, but only when they are non-nil.
    no_tracking_cats = "true"; -- set no_tracking_cats
    local EditorCount; -- used only for choosing {ed.) or (eds.) annotation at end of editor name-list
    end
    do
    for _, v in ipairs (cfg.uncategorized_subpages) do -- cycle through page name patterns
    local last_first_list;
    if this_page.text:match (v) then -- test page name against each pattern
    local maximum;
    no_tracking_cats = "true"; -- set no_tracking_cats
    local control = {
    break; -- bail out if one is found
    format = NameListFormat, -- empty string or 'vanc'
    maximum = nil, -- as if display-authors or display-editors not set
    lastauthoramp = LastAuthorAmp,
    page_name = this_page.text -- get current page name so that we don't wikilink to it via editorlinkn
    };
     
    do -- do editor name list first because coauthors can modify control table
    maximum , editor_etal = get_display_authors_editors (A['DisplayEditors'], #e, 'editors', editor_etal);
    -- Preserve old-style implicit et al.
    if not is_set(maximum) and #e == 4 then  
    maximum = 3;
    table.insert( z.message_tail, { set_error('implict_etal_editor', {}, true) } );
    end
    end
    end
    end
    -- check for extra |page=, |pages= or |at= parameters. (also sheet and sheets while we're at it)
    utilities.select_one (args, {'page', 'p', 'pp', 'pages', 'at', 'sheet', 'sheets'}, 'err_redundant_parameters'); -- this is a dummy call simply to get the error message and category


    control.maximum = maximum;
    local coins_pages;
    last_first_list, EditorCount = list_people(control, e, editor_etal);
    Page, Pages, At, coins_pages = insource_loc_get (Page, A:ORIGIN('Page'), Pages, A:ORIGIN('Pages'), At);


    if is_set (Editors) then
    local NoPP = is_valid_parameter_value (A['NoPP'], A:ORIGIN('NoPP'), cfg.keywords_lists['yes_true_y'], nil);
    if editor_etal then
    Editors = Editors .. ' ' .. cfg.messages['et al']; -- add et al. to editors parameter beause |display-editors=etal
    EditorCount = 2; -- with et al., |editors= is multiple names; spoof to display (eds.) annotation
    else
    EditorCount = 2; -- we don't know but assume |editors= is multiple names; spoof to display (eds.) annotation
    end
    else
    Editors = last_first_list; -- either an author name list or an empty string
    end


    if 1 == EditorCount and (true == editor_etal or 1 < #e) then -- only one editor displayed but includes etal then  
    if utilities.is_set (PublicationPlace) and utilities.is_set (Place) then -- both |publication-place= and |place= (|location=) allowed if different
    EditorCount = 2; -- spoof to display (eds.) annotation
    utilities.add_prop_cat ('location test'); -- add property cat to evaluate how often PublicationPlace and Place are used together
    end
    if PublicationPlace == Place then
    Place = ''; -- unset; don't need both if they are the same
    end
    end
    do -- now do translators
    elseif not utilities.is_set (PublicationPlace) and utilities.is_set (Place) then -- when only |place= (|location=) is set ...
    control.maximum = #t; -- number of translators
    PublicationPlace = Place; -- promote |place= (|location=) to |publication-place
    Translators = list_people(control, t, false); -- et al not currently supported
    end
    end
    do -- now do authors
    control.maximum , author_etal = get_display_authors_editors (A['DisplayAuthors'], #a, 'authors', author_etal);


    if is_set(Coauthors) then -- if the coauthor field is also used, prevent ampersand and et al. formatting.
    if PublicationPlace == Place then Place = ''; end -- don't need both if they are the same
    control.lastauthoramp = nil;
    control.maximum = #a + 1;
    local URL_origin = A:ORIGIN('URL'); -- get name of parameter that holds URL
    end
    local ChapterURL_origin = A:ORIGIN('ChapterURL'); -- get name of parameter that holds ChapterURL
    local ScriptChapter = A['ScriptChapter'];
    last_first_list = list_people(control, a, author_etal);
    local ScriptChapter_origin = A:ORIGIN ('ScriptChapter');
    local Format = A['Format'];
    local ChapterFormat = A['ChapterFormat'];
    local TransChapter = A['TransChapter'];
    local TransChapter_origin = A:ORIGIN ('TransChapter');
    local TransTitle = A['TransTitle'];
    local ScriptTitle = A['ScriptTitle'];
    --[[
    Parameter remapping for cite encyclopedia:
    When the citation has these parameters:
    |encyclopedia= and |title= then map |title= to |article= and |encyclopedia= to |title=
    |encyclopedia= and |article= then map |encyclopedia= to |title=


    if is_set (Authors) then
    |trans-title= maps to |trans-chapter= when |title= is re-mapped
    Authors, author_etal = name_has_etal (Authors, author_etal, false); -- find and remove variations on et al.
    |url= maps to |chapter-url= when |title= is remapped
    if author_etal then
    Authors = Authors .. ' ' .. cfg.messages['et al']; -- add et al. to authors parameter
    All other combinations of |encyclopedia=, |title=, and |article= are not modified
    end
    else
    ]]
    Authors = last_first_list; -- either an author name list or an empty string
    end


    end -- end of do
    local Encyclopedia = A['Encyclopedia']; -- used as a flag by this module and by ~/COinS


    if not is_set(Authors) and is_set(Coauthors) then -- coauthors aren't displayed if one of authors=, authorn=, or lastn= isn't specified
    if utilities.is_set (Encyclopedia) then -- emit error message when Encyclopedia set but template is other than {{cite encyclopedia}} or {{citation}}
    table.insert( z.message_tail, { set_error('coauthors_missing_author', {}, true) } ); -- emit error message
    if 'encyclopaedia' ~= config.CitationClass and 'citation' ~= config.CitationClass then
    table.insert (z.message_tail, {utilities.set_message ('err_parameter_ignored', {A:ORIGIN ('Encyclopedia')}, true)});
    Encyclopedia = nil; -- unset because not supported by this template
    end
    end
    end
    end


     
    if ('encyclopaedia' == config.CitationClass) or ('citation' == config.CitationClass and utilities.is_set (Encyclopedia)) then
     
    if utilities.is_set (Periodical) and utilities.is_set (Encyclopedia) then -- when both set emit an error
    --[[
    table.insert (z.message_tail, {utilities.set_message ('err_redundant_parameters', {utilities.wrap_style ('parameter', A:ORIGIN ('Encyclopedia')) .. ' and ' .. utilities.wrap_style ('parameter', Periodical_origin)}, true )});
    do -- do-block to limit scope of last_first_list
    local last_first_list;
    local maximum = A['DisplayAuthors'];
     
    maximum , author_etal = get_display_authors_editors (maximum, #a, 'authors', author_etal);
     
    local control = {
    format = NameListFormat, -- empty string or 'vanc'
    maximum = maximum,
    lastauthoramp = LastAuthorAmp,
    page_name = this_page.text -- get current page name so that we don't wikilink to it via authorlinkn
    };
    if is_set(Coauthors) then -- if the coauthor field is also used, prevent ampersand and et al. formatting.
    control.lastauthoramp = nil;
    control.maximum = #a + 1;
    end
    end
    last_first_list = list_people(control, a, author_etal);


    if is_set (Authors) then
    if utilities.is_set (Encyclopedia) then
    Authors, author_etal = name_has_etal (Authors, author_etal, false); -- find and remove variations on et al.
    Periodical = Encyclopedia; -- error or no, set Periodical to Encyclopedia; allow periodical without encyclopedia
    if author_etal then
    Periodical_origin = A:ORIGIN ('Encyclopedia');
    Authors = Authors .. ' ' .. cfg.messages['et al']; -- add et al. to authors parameter
    end
    else
    Authors = last_first_list; -- either an author name list or an empty string
    end
    end


    end -- end of do
    if utilities.is_set (Periodical) then -- Periodical is set when |encyclopedia= is set
    if utilities.is_set (Title) or utilities.is_set (ScriptTitle) then
    if not utilities.is_set (Chapter) then
    Chapter = Title; -- |encyclopedia= and |title= are set so map |title= to |article= and |encyclopedia= to |title=
    ScriptChapter = ScriptTitle;
    ScriptChapter_origin = A:ORIGIN('ScriptTitle')
    TransChapter = TransTitle;
    ChapterURL = URL;
    ChapterURL_origin = URL_origin;


    if not is_set(Authors) and is_set(Coauthors) then -- coauthors aren't displayed if one of authors=, authorn=, or lastn= isn't specified
    ChapterUrlAccess = UrlAccess;
    table.insert( z.message_tail, { set_error('coauthors_missing_author', {}, true) } ); -- emit error message
    end


    local EditorCount; -- used only for choosing {ed.) or (eds.) annotation at end of editor name-list
    if not utilities.is_set (ChapterURL) and utilities.is_set (TitleLink) then
    do
    Chapter = utilities.make_wikilink (TitleLink, Chapter);
    local last_first_list;
    end
    local maximum = A['DisplayEditors'];
    Title = Periodical;
     
    ChapterFormat = Format;
    maximum , editor_etal = get_display_authors_editors (maximum, #e, 'editors', editor_etal);
    Periodical = ''; -- redundant so unset
    -- Preserve old-style implicit et al.
    TransTitle = '';
    if not is_set(maximum) and #e == 4 then
    URL = '';
    maximum = 3;
    Format = '';
    table.insert( z.message_tail, { set_error('implict_etal_editor', {}, true) } );
    TitleLink = '';
    ScriptTitle = '';
    end
    elseif utilities.is_set (Chapter) then -- |title= not set
    Title = Periodical; -- |encyclopedia= set and |article= set so map |encyclopedia= to |title=
    Periodical = ''; -- redundant so unset
    end
    end
    end
    end


    local control = {
    -- special case for cite techreport.
    format = NameListFormat, -- empty string or 'vanc'
    local ID = A['ID'];
    maximum = maximum,
    if (config.CitationClass == "techreport") then -- special case for cite techreport
    lastauthoramp = LastAuthorAmp,
    if utilities.is_set (A['Number']) then -- cite techreport uses 'number', which other citations alias to 'issue'
    page_name = this_page.text -- get current page name so that we don't wikilink to it via editorlinkn
    if not utilities.is_set (ID) then -- can we use ID for the "number"?
    };
    ID = A['Number']; -- yes, use it
     
    else -- ID has a value so emit error message
    last_first_list, EditorCount = list_people(control, e, editor_etal);
    table.insert( z.message_tail, { utilities.set_message ('err_redundant_parameters', {utilities.wrap_style ('parameter', 'id') .. ' and ' .. utilities.wrap_style ('parameter', 'number')}, true )});
     
    if is_set (Editors) then
    if editor_etal then
    Editors = Editors .. ' ' .. cfg.messages['et al']; -- add et al. to editors parameter beause |display-editors=etal
    EditorCount = 2; -- with et al., |editors= is multiple names; spoof to display (eds.) annotation
    else
    EditorCount = 2; -- we don't know but assume |editors= is multiple names; spoof to display (eds.) annotation
    end
    end
    else
    end
    Editors = last_first_list; -- either an author name list or an empty string
    end
     
    if 1 == EditorCount and (true == editor_etal or 1 < #e) then -- only one editor displayed but includes etal then
    EditorCount = 2; -- spoof to display (eds.) annotation
    end
    end
    end
    ]]


    -- apply |[xx-]format= styling; at the end, these parameters hold correctly styled format annotation,
    -- Account for the oddity that is {{cite conference}}, before generation of COinS data.
    -- an error message if the associated url is not set, or an empty string for concatenation
    local ChapterLink -- = A['ChapterLink']; -- deprecated as a parameter but still used internally by cite episode
    ArchiveFormat = style_format (ArchiveFormat, ArchiveURL, 'archive-format', 'archive-url');
    local Conference = A['Conference'];
    ChapterFormat = style_format (ChapterFormat, ChapterURL, 'chapter-format', 'chapter-url');
    local BookTitle = A['BookTitle'];
    ConferenceFormat = style_format (ConferenceFormat, ConferenceURL, 'conference-format', 'conference-url');
    local TransTitle_origin = A:ORIGIN ('TransTitle');
    Format = style_format (Format, URL, 'format', 'url');
    if 'conference' == config.CitationClass then
    LayFormat = style_format (LayFormat, LayURL, 'lay-format', 'lay-url');
    if utilities.is_set (BookTitle) then
    TranscriptFormat = style_format (TranscriptFormat, TranscriptURL, 'transcript-format', 'transcripturl');
    Chapter = Title;
     
    Chapter_origin = 'title';
    if not is_set(URL) then --and
    -- ChapterLink = TitleLink; -- |chapter-link= is deprecated
    -- not is_set(ArchiveURL) then --and -- prevents format_missing_url error from registering
    ChapterURL = URL;
    -- not is_set(ConferenceURL) and -- TODO: keep this here? conference as part of cite web or cite podcast?
    ChapterUrlAccess = UrlAccess;
    -- not is_set(TranscriptURL) then -- TODO: remove? |transcript-url= and |transcript= has separate test
    ChapterURL_origin = URL_origin;
    URL_origin = '';
    -- Test if cite web or cite podcast |url= is missing or empty
    ChapterFormat = Format;
    if in_array(config.CitationClass, {"web","podcast", "mailinglist"}) then
    TransChapter = TransTitle;
    table.insert( z.message_tail, { set_error( 'cite_web_url', {}, true ) } );
    TransChapter_origin = TransTitle_origin;
    end
    Title = BookTitle;
    Format = '';
    -- Test if accessdate is given without giving a URL
    -- TitleLink = '';
    if is_set(AccessDate) and not is_set(ChapterURL)then -- ChapterURL may be set when the others are not set; TODO: move this to a separate test?
    TransTitle = '';
    table.insert( z.message_tail, { set_error( 'accessdate_missing_url', {}, true ) } );
    URL = '';
    AccessDate = '';
    end
    end
    elseif 'speech' ~= config.CitationClass then
    Conference = ''; -- not cite conference or cite speech so make sure this is empty string
    end
    end
     
    local OriginalURL, OriginalFormat; -- TODO: swap chapter and title here so that archive applies to most specific if both are set?
    -- CS1/2 mode
    DeadURL = DeadURL:lower(); -- used later when assembling archived text
    local Mode = is_valid_parameter_value (A['Mode'], A:ORIGIN('Mode'), cfg.keywords_lists['mode'], '');
    if is_set( ArchiveURL ) then
    -- separator character and postscript
    if is_set (URL) then
    local sepc, PostScript = set_style (Mode:lower(), A['PostScript'], config.CitationClass);
    OriginalURL = URL; -- save copy of original source URL
    -- controls capitalization of certain static text
    OriginalFormat = Format; -- and original |format=
    local use_lowercase = ( sepc == ',' );
    if 'no' ~= DeadURL then -- if URL set then archive-url applies to it
    URL = ArchiveURL -- swap-in the archive's url
    -- cite map oddities
    URLorigin = A:ORIGIN('ArchiveURL') -- name of archive url parameter for error messages
    local Cartography = "";
    Format = ArchiveFormat or ''; -- swap in archive's format
    local Scale = "";
    end
    local Sheet = A['Sheet'] or '';
    elseif is_set (ChapterURL) then -- URL not set so if chapter-url is set apply archive url to it
    local Sheets = A['Sheets'] or '';
    OriginalURL = ChapterURL; -- save copy of source chapter's url for archive text
    if config.CitationClass == "map" then
    OriginalFormat = ChapterFormat; -- and original |format=
    if utilities.is_set (Chapter) then
    if 'no' ~= DeadURL then
    table.insert( z.message_tail, { utilities.set_message ( 'err_redundant_parameters', {utilities.wrap_style ('parameter', 'map') .. ' and ' .. utilities.wrap_style ('parameter', Chapter_origin)}, true ) } ); -- add error message
    ChapterURL = ArchiveURL -- swap-in the archive's url
    URLorigin = A:ORIGIN('ArchiveURL') -- name of archive url parameter for error messages
    ChapterFormat = ArchiveFormat or ''; -- swap in archive's format
    end
    end
    end
    end
    Chapter = A['Map'];
    Chapter_origin = A:ORIGIN('Map');
    ChapterURL = A['MapURL'];
    ChapterURL_origin = A:ORIGIN('MapURL');
    TransChapter = A['TransMap'];
    ScriptChapter = A['ScriptMap']
    ScriptChapter_origin = A:ORIGIN('ScriptMap')
     
    ChapterUrlAccess = MapUrlAccess;
    ChapterFormat = A['MapFormat'];


    if in_array(config.CitationClass, {"web","news","journal","pressrelease","podcast", "newsgroup", 'arxiv'}) or
    Cartography = A['Cartography'];
    ('citation' == config.CitationClass and is_set (Periodical) and not is_set (Encyclopedia)) then
    if utilities.is_set ( Cartography ) then
    if is_set (Chapter) or is_set (TransChapter) or is_set (ChapterURL) or is_set (ScriptChapter) then -- chapter parameters not supported for these citation types
    Cartography = sepc .. " " .. wrap_msg ('cartography', Cartography, use_lowercase);
    table.insert( z.message_tail, { set_error( 'chapter_ignored', {A:ORIGIN ('Chapter')}, true ) } ); -- add error message
    end
    Chapter = ''; -- set them to empty string to be safe with concatenation
    Scale = A['Scale'];
    TransChapter = '';
    if utilities.is_set ( Scale ) then
    ChapterURL = '';
    Scale = sepc .. " " .. Scale;
    ScriptChapter = '';
    end
    else -- otherwise, format chapter / article title
    Chapter = format_chapter_title (ScriptChapter, Chapter, TransChapter, ChapterURL, ChapterURLorigin);
    if is_set (Chapter) then
    if 'map' == config.CitationClass and is_set (TitleType) then
    Chapter = Chapter .. ' ' .. TitleType;
    end
    Chapter = Chapter .. ChapterFormat .. sepc .. ' ';
    end
    end
    end
    end


    -- Format main title.
    -- Account for the oddities that are {{cite episode}} and {{cite serial}}, before generation of COinS data.
    if is_set(TitleLink) and is_set(Title) then
    local Series = A['Series'];
    Title = "[[" .. TitleLink .. "|" .. Title .. "]]"
    if 'episode' == config.CitationClass or 'serial' == config.CitationClass then
    end
    local SeriesLink = A['SeriesLink'];
     
    SeriesLink = link_title_ok (SeriesLink, A:ORIGIN ('SeriesLink'), Series, 'series'); -- check for wiki-markup in |series-link= or wiki-markup in |series= when |series-link= is set


    if in_array(config.CitationClass, {"web","news","journal","pressrelease","podcast", "newsgroup", "mailinglist", 'arxiv'}) or
    local Network = A['Network'];
    ('citation' == config.CitationClass and is_set (Periodical) and not is_set (Encyclopedia)) or
    local Station = A['Station'];
    ('map' == config.CitationClass and is_set (Periodical)) then -- special case for cite map when the map is in a periodical treat as an article
    local s, n = {}, {};
    Title = kern_quotes (Title); -- if necessary, separate title's leading and trailing quote marks from Module provided quote marks
    -- do common parameters first
    Title = wrap_style ('quoted-title', Title);
    if utilities.is_set (Network) then table.insert(n, Network); end
    if utilities.is_set (Station) then table.insert(n, Station); end
    Title = script_concatenate (Title, ScriptTitle); -- <bdi> tags, lang atribute, categorization, etc; must be done after title is wrapped
    ID = table.concat(n, sepc .. ' ');
    TransTitle= wrap_style ('trans-quoted-title', TransTitle );
    elseif 'report' == config.CitationClass then -- no styling for cite report
    if 'episode' == config.CitationClass then -- handle the oddities that are strictly {{cite episode}}
    Title = script_concatenate (Title, ScriptTitle); -- <bdi> tags, lang atribute, categorization, etc; must be done after title is wrapped
    local Season = A['Season'];
    TransTitle= wrap_style ('trans-quoted-title', TransTitle ); -- for cite report, use this form for trans-title
    local SeriesNumber = A['SeriesNumber'];
    else
    Title = wrap_style ('italic-title', Title);
    Title = script_concatenate (Title, ScriptTitle); -- <bdi> tags, lang atribute, categorization, etc; must be done after title is wrapped
    TransTitle = wrap_style ('trans-italic-title', TransTitle);
    end


    TransError = "";
    if utilities.is_set (Season) and utilities.is_set (SeriesNumber) then -- these are mutually exclusive so if both are set
    if is_set(TransTitle) then
    table.insert( z.message_tail, { utilities.set_message ( 'err_redundant_parameters', {utilities.wrap_style ('parameter', 'season') .. ' and ' .. utilities.wrap_style ('parameter', 'seriesno')}, true ) } ); -- add error message
    if is_set(Title) then
    SeriesNumber = ''; -- unset; prefer |season= over |seriesno=
    TransTitle = " " .. TransTitle;
    end
    else
    -- assemble a table of parts concatenated later into Series
    TransError = " " .. set_error( 'trans_missing_title', {'title'} );
    if utilities.is_set (Season) then table.insert(s, wrap_msg ('season', Season, use_lowercase)); end
    end
    if utilities.is_set (SeriesNumber) then table.insert(s, wrap_msg ('seriesnum', SeriesNumber, use_lowercase)); end
    end
    if utilities.is_set (Issue) then table.insert(s, wrap_msg ('episode', Issue, use_lowercase)); end
    Issue = ''; -- unset because this is not a unique parameter
    Title = Title .. TransTitle;
    Chapter = Title; -- promote title parameters to chapter
    ScriptChapter = ScriptTitle;
    if is_set(Title) then
    ScriptChapter_origin = A:ORIGIN('ScriptTitle');
    if not is_set(TitleLink) and is_set(URL) then  
    ChapterLink = TitleLink; -- alias |episode-link=
    Title = external_link( URL, Title ) .. TransError .. Format;
    TransChapter = TransTitle;
    URL = "";
    ChapterURL = URL;
    Format = "";
    ChapterUrlAccess = UrlAccess;
    else
    ChapterURL_origin = URL_origin;
    Title = Title .. TransError;
    Title = Series; -- promote series to title
    TitleLink = SeriesLink;
    Series = table.concat(s, sepc .. ' '); -- this is concatenation of season, seriesno, episode number
     
    if utilities.is_set (ChapterLink) and not utilities.is_set (ChapterURL) then -- link but not URL
    Chapter = utilities.make_wikilink (ChapterLink, Chapter);
    elseif utilities.is_set (ChapterLink) and utilities.is_set (ChapterURL) then -- if both are set, URL links episode;
    Series = utilities.make_wikilink (ChapterLink, Series);
    end
    URL = ''; -- unset
    TransTitle = '';
    ScriptTitle = '';
    else -- now oddities that are cite serial
    Issue = ''; -- unset because this parameter no longer supported by the citation/core version of cite serial
    Chapter = A['Episode']; -- TODO: make |episode= available to cite episode someday?
    if utilities.is_set (Series) and utilities.is_set (SeriesLink) then
    Series = utilities.make_wikilink (SeriesLink, Series);
    end
    Series = utilities.wrap_style ('italic-title', Series); -- series is italicized
    end
    end
    -- end of {{cite episode}} stuff
     
    -- handle type parameter for those CS1 citations that have default values
    local TitleType = A['TitleType'];
    local Degree = A['Degree'];
    if utilities.in_array (config.CitationClass, {"AV-media-notes", "interview", "mailinglist", "map", "podcast", "pressrelease", "report", "techreport", "thesis"}) then
    TitleType = set_titletype (config.CitationClass, TitleType);
    if utilities.is_set (Degree) and "Thesis" == TitleType then -- special case for cite thesis
    TitleType = Degree .. ' ' .. cfg.title_types ['thesis']:lower();
    end
    end
    end
    end


    if is_set(Place) then
    if utilities.is_set (TitleType) then -- if type parameter is specified
    Place = " " .. wrap_msg ('written', Place, use_lowercase) .. sepc .. " ";
    TitleType = utilities.substitute ( cfg.messages['type'], TitleType); -- display it in parentheses
    -- TODO: Hack on TitleType to fix bunched parentheses problem
    end
    end


    if is_set (Conference) then
    -- legacy: promote PublicationDate to Date if neither Date nor Year are set.
    if is_set (ConferenceURL) then
    local Date = A['Date'];
    Conference = external_link( ConferenceURL, Conference );
    local Date_origin; -- to hold the name of parameter promoted to Date; required for date error messaging
    end
    local PublicationDate = A['PublicationDate'];
    Conference = sepc .. " " .. Conference .. ConferenceFormat;
    local Year = A['Year'];
    elseif is_set(ConferenceURL) then
    Conference = sepc .. " " .. external_link( ConferenceURL, nil, ConferenceURLorigin );
    end


    if not is_set(Position) then
    if not utilities.is_set (Date) then
    local Minutes = A['Minutes'];
    Date = Year; -- promote Year to Date
    if is_set(Minutes) then
    Year = nil; -- make nil so Year as empty string isn't used for CITEREF
    Position = " " .. Minutes .. " " .. cfg.messages['minutes'];
    if not utilities.is_set (Date) and utilities.is_set (PublicationDate) then -- use PublicationDate when |date= and |year= are not set
    else
    Date = PublicationDate; -- promote PublicationDate to Date
    local Time = A['Time'];
    PublicationDate = ''; -- unset, no longer needed
    if is_set(Time) then
    Date_origin = A:ORIGIN('PublicationDate'); -- save the name of the promoted parameter
    local TimeCaption = A['TimeCaption']
    else
    if not is_set(TimeCaption) then
    Date_origin = A:ORIGIN('Year'); -- save the name of the promoted parameter
    TimeCaption = cfg.messages['event'];
    if sepc ~= '.' then
    TimeCaption = TimeCaption:lower();
    end
    end
    Position = " " .. TimeCaption .. " " .. Time;
    end
    end
    end
    else
    else
    Position = " " .. Position;
    Date_origin = A:ORIGIN('Date'); -- not a promotion; name required for error messaging
    At = '';
    end
    end
    if PublicationDate == Date then PublicationDate = ''; end -- if PublicationDate is same as Date, don't display in rendered citation
    --[[
    Go test all of the date-holding parameters for valid MOS:DATE format and make sure that dates are real dates. This must be done before we do COinS because here is where
    we get the date used in the metadata.
    if not is_set(Page) then
    Date validation supporting code is in Module:Citation/CS1/Date_validation
    if is_set(Pages) then
    ]]
    if is_set(Periodical) and
     
    not in_array(config.CitationClass, {"encyclopaedia","web","book","news","podcast"}) then
    local DF = is_valid_parameter_value (A['DF'], A:ORIGIN('DF'), cfg.keywords_lists['df'], '');
    Pages = ": " .. Pages;
    if not utilities.is_set (DF) then
    elseif tonumber(Pages) ~= nil then
    DF = cfg.global_df; -- local |df= if present overrides global df set by {{use xxx date}} template
    Pages = sepc .." " .. PPrefix .. Pages;
    else
    Pages = sepc .." " .. PPPrefix .. Pages;
    end
    end
    else
    if is_set(Periodical) and
    not in_array(config.CitationClass, {"encyclopaedia","web","book","news","podcast"}) then
    Page = ": " .. Page;
    else
    Page = sepc .." " .. PPrefix .. Page;
    end
    end
    end


    if 'map' == config.CitationClass then -- cite map oddity done after COinS call (and with other in-source locators)
    local ArchiveURL;
    if is_set (Sheet) or is_set (Sheets) then
    local ArchiveDate;
    local err_msg1 = 'sheet=, &#124;sheets'; -- default error message in case any of page pages or at are set
    local ArchiveFormat = A['ArchiveFormat'];
    local err_msg2;
     
    if is_set (Page) or is_set (Pages) or is_set (At) then -- are any set?
    ArchiveURL, ArchiveDate = archive_url_check (A['ArchiveURL'], A['ArchiveDate'])
    err_msg2 = 'page=, &#124;pages=, &#124;at'; -- a generic error message
    ArchiveFormat = style_format (ArchiveFormat, ArchiveURL, 'archive-format', 'archive-url');
    Page = ''; Pages = ''; At = '';
    elseif is_set (Sheet) and is_set (Sheets) then -- if both are set make error message
    ArchiveURL, ArchiveDate = is_unique_archive_url (ArchiveURL, URL, ChapterURL, A:ORIGIN('ArchiveURL'), ArchiveDate); -- add error message when URL or ChapterURL == ArchiveURL
    err_msg1 = 'sheet';
     
    err_msg2 = 'sheets';
    end
    local AccessDate = A['AccessDate'];
    if is_set (err_msg2) then
    local LayDate = A['LayDate'];
    table.insert( z.message_tail, { set_error( 'redundant_parameters', {wrap_style ('parameter', err_msg1) .. ' and ' .. wrap_style ('parameter', err_msg2)}, true ) } ); -- add error message
    local COinS_date = {}; -- holds date info extracted from |date= for the COinS metadata by Module:Date verification
    end
    local DoiBroken = A['DoiBroken'];
    if not is_set (Sheet) then -- do sheet static text and formatting; Sheet has priority over Sheets if both provided
    local Embargo = A['Embargo'];
    if is_set (Sheets) then
    local anchor_year; -- used in the CITEREF identifier
    if is_set (Periodical) then
    do -- create defined block to contain local variables error_message, date_parameters_list, mismatch
    Sheet = ": Sheets " .. Sheets; -- because Sheet has priority, no need to support both later on
    local error_message = '';
    else
    -- AirDate has been promoted to Date so not necessary to check it
    Sheet = sepc .. " Sheets " .. Sheets;
    local date_parameters_list = {
    end
    ['access-date'] = {val = AccessDate, name = A:ORIGIN ('AccessDate')},
    end
    ['archive-date'] = {val = ArchiveDate, name = A:ORIGIN ('ArchiveDate')},
    else
    ['date'] = {val = Date, name = Date_origin},
    if is_set (Periodical) then
    ['doi-broken-date'] = {val = DoiBroken, name = A:ORIGIN ('DoiBroken')},
    Sheet = ": Sheet " .. Sheet;
    ['pmc-embargo-date'] = {val = Embargo, name = A:ORIGIN ('Embargo')},
    else
    ['lay-date'] = {val = LayDate, name = A:ORIGIN ('LayDate')},
    Sheet = sepc .. " Sheet " .. Sheet;
    ['publication-date'] = {val = PublicationDate, name = A:ORIGIN ('PublicationDate')},
    end
    ['year'] = {val = Year, name = A:ORIGIN ('Year')},
    end
    };
     
    local error_list = {};
    anchor_year, Embargo = validation.dates(date_parameters_list, COinS_date, error_list);
     
    -- start temporary Julian / Gregorian calendar uncertainty categorization
    if COinS_date.inter_cal_cat then
    utilities.add_prop_cat ('jul_greg_uncertainty');
    end
    end
    end
    -- end temporary Julian / Gregorian calendar uncertainty categorization


    At = is_set(At) and (sepc .. " " .. At) or "";
    if utilities.is_set (Year) and utilities.is_set (Date) then -- both |date= and |year= not normally needed;  
    Position = is_set(Position) and (sepc .. " " .. Position) or "";
    validation.year_date_check (Year, A:ORIGIN ('Year'), Date, A:ORIGIN ('Date'), error_list);
    if config.CitationClass == 'map' then
    end
    local Section = A['Section'];
    local Sections = A['Sections'];
    local Inset = A['Inset'];
    if is_set( Inset ) then
    if 0 == #error_list then -- error free dates only; 0 when error_list is empty
    Inset = sepc .. " " .. wrap_msg ('inset', Inset, use_lowercase);
    local modified = false; -- flag
    end
    if validation.edtf_transform (date_parameters_list) then -- edtf dates to MOS compliant format
    modified = true;
    end


    if is_set( Sections ) then
    if utilities.is_set (DF) then -- if we need to reformat dates
    Section = sepc .. " " .. wrap_msg ('sections', Sections, use_lowercase);
    modified = validation.reformat_dates (date_parameters_list, DF); -- reformat to DF format, use long month names if appropriate
    elseif is_set( Section ) then
    end
    Section = sepc .. " " .. wrap_msg ('section', Section, use_lowercase);
     
    if true == validation.date_hyphen_to_dash (date_parameters_list) then -- convert hyphens to dashes where appropriate
    modified = true;
    utilities.set_message ('maint_date_format'); -- hyphens were converted so add maint category
    end
    -- for those wikis that can and want to have English date names translated to the local language,
    -- uncomment the next three lines.  Not supported by en.wiki (for obvious reasons)
    -- set validation.date_name_xlate() second argument to true to translate English digits to local digits (will translate ymd dates)
    -- if validation.date_name_xlate (date_parameters_list, false) then
    -- modified = true;
    -- end
     
    if modified then -- if the date_parameters_list values were modified
    AccessDate = date_parameters_list['access-date'].val; -- overwrite date holding parameters with modified values
    ArchiveDate = date_parameters_list['archive-date'].val;
    Date = date_parameters_list['date'].val;
    DoiBroken = date_parameters_list['doi-broken-date'].val;
    LayDate = date_parameters_list['lay-date'].val;
    PublicationDate = date_parameters_list['publication-date'].val;
    end
    else
    table.insert (z.message_tail, {utilities.set_message ('err_bad_date', {utilities.make_sep_list (#error_list, error_list)}, true)}); -- add this error message
    end
    end
    At = At .. Inset .. Section;
    end -- end of do
    end


    if is_set (Language) then
    local ID_list = {}; -- sequence table of rendered identifiers
    Language = language_parameter (Language); -- format, categories, name from ISO639-1, etc
    local ID_list_coins = {}; -- table of identifiers and their values from args; key is same as cfg.id_handlers's key
    else
    local Class = A['Class']; -- arxiv class identifier
    Language=""; -- language not specified so make sure this is an empty string;
    end
    local ID_support = {
    {A['ASINTLD'], 'ASIN', 'err_asintld_missing_asin', A:ORIGIN ('ASINTLD')},
    {DoiBroken, 'DOI', 'err_doibroken_missing_doi', A:ORIGIN ('DoiBroken')},
    {Embargo, 'PMC', 'err_embargo_missing_pmc', A:ORIGIN ('Embargo')},
    }


    Others = is_set(Others) and (sepc .. " " .. Others) or "";
    ID_list, ID_list_coins = identifiers.identifier_lists_get (args, {DoiBroken = DoiBroken, ASINTLD = A['ASINTLD'], Embargo = Embargo, Class = Class}, ID_support);
    if is_set (Translators) then
    Others = sepc .. ' Translated by ' .. Translators .. Others;  
    end


    TitleNote = is_set(TitleNote) and (sepc .. " " .. TitleNote) or "";
    -- Account for the oddities that are {{cite arxiv}}, {{cite biorxiv}}, {{cite citeseerx}}, {{cite ssrn}}, before generation of COinS data.
    if is_set (Edition) then
    if utilities.in_array (config.CitationClass, whitelist.preprint_template_list) then
    if Edition:match ('%f[%a][Ee]d%.?$') or Edition:match ('%f[%a][Ee]dition$') then
    if not utilities.is_set (ID_list_coins[config.CitationClass:upper()]) then -- |arxiv= or |eprint= required for cite arxiv; |biorxiv= & |citeseerx= required for their templates
    add_maint_cat ('extra_text', 'edition');
    table.insert (z.message_tail, {utilities.set_message ('err_' .. config.CitationClass .. '_missing', {}, true)}); -- add error message
    end
    end
    Edition = " " .. wrap_msg ('edition', Edition);
     
    else
    Periodical = ({['arxiv'] = 'arXiv', ['biorxiv'] = 'bioRxiv', ['citeseerx'] = 'CiteSeerX', ['ssrn'] = 'Social Science Research Network'})[config.CitationClass];
    Edition = '';
    end
    end
    Issue = is_set(Issue) and (" (" .. Issue .. ")") or "";
    Series = is_set(Series) and (sepc .. " " .. Series) or "";
    OrigYear = is_set(OrigYear) and (" [" .. OrigYear .. "]") or "";
    Agency = is_set(Agency) and (sepc .. " " .. Agency) or "";


    if is_set(Volume) then
    -- Link the title of the work if no |url= was provided, but we have a |pmc= or a |doi= with |doi-access=free
    if ( mw.ustring.len(Volume) > 4 )
     
      then Volume = sepc .." " .. Volume;
    if config.CitationClass == "journal" and not utilities.is_set (URL) and not utilities.is_set (TitleLink) and not utilities.in_array (cfg.keywords_xlate[Title], {'off', 'none'}) then -- TODO: remove 'none' once existing citations have been switched to 'off', so 'none' can be used as token for "no title" instead
      else Volume = " <b>" .. hyphen_to_dash(Volume) .. "</b>";
    if 'none' ~= cfg.keywords_xlate[auto_select] then -- if auto-linking not disabled
    if identifiers.auto_link_urls[auto_select] then -- manual selection
    URL = identifiers.auto_link_urls[auto_select]; -- set URL to be the same as identifier's external link
    URL_origin = cfg.id_handlers[auto_select:upper()].parameters[1]; -- set URL_origin to parameter name for use in error message if citation is missing a |title=
    elseif identifiers.auto_link_urls['pmc'] then -- auto-select PMC
    URL = identifiers.auto_link_urls['pmc']; -- set URL to be the same as the PMC external link if not embargoed
    URL_origin = cfg.id_handlers['PMC'].parameters[1]; -- set URL_origin to parameter name for use in error message if citation is missing a |title=
    elseif identifiers.auto_link_urls['doi'] then -- auto-select DOI
    URL = identifiers.auto_link_urls['doi'];
    URL_origin = cfg.id_handlers['DOI'].parameters[1];
    end
    end
     
    if utilities.is_set (URL) and utilities.is_set (AccessDate) then -- access date requires |url=; identifier-created URL is not |url=
    table.insert( z.message_tail, { utilities.set_message ( 'err_accessdate_missing_url', {}, true ) } ); -- add an error message
    AccessDate = ''; -- unset
    end
    end
    end
    end


    ------------------------------------ totally unrelated data
    -- At this point fields may be nil if they weren't specified in the template use.  We can use that fact.
    if is_set(Via) then
    -- Test if citation has no title
    Via = " " .. wrap_msg ('via', Via);
    if not utilities.is_set (Title) and not utilities.is_set (TransTitle) and not utilities.is_set (ScriptTitle) then -- has special case for cite episode
    table.insert( z.message_tail, { utilities.set_message ( 'err_citation_missing_title', {'episode' == config.CitationClass and 'series' or 'title'}, true ) } );
    end
    end


    --[[
    if utilities.in_array (cfg.keywords_xlate[Title], {'off', 'none'}) and
    Subscription implies paywall; Registration does not. If both are used in a citation, the subscription required link
    utilities.in_array (config.CitationClass, {'journal', 'citation'}) and
    note is displayed. There are no error messages for this condition.
    (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and
     
    ('journal' == Periodical_origin or 'script-journal' == ScriptPeriodical_origin) then -- special case for journal cites
    ]]
    Title = ''; -- set title to empty string
    if is_set (SubscriptionRequired) then
    utilities.set_message ('maint_untitled'); -- add maint cat
    SubscriptionRequired = sepc .. " " .. cfg.messages['subscription']; -- subscription required message
    elseif is_set (RegistrationRequired) then
    SubscriptionRequired = sepc .. " " .. cfg.messages['registration']; -- registration required message
    else
    SubscriptionRequired = ''; -- either or both might be set to something other than yes true y
    end
    end


    if is_set(AccessDate) then
    check_for_url ({ -- add error message when any of these parameters hold a URL
    local retrv_text = " " .. cfg.messages['retrieved']
    ['title'] = Title,
    [A:ORIGIN('Chapter')] = Chapter,
    [Periodical_origin] = Periodical,
    [PublisherName_origin] = PublisherName
    });


    AccessDate = nowrap_date (AccessDate); -- wrap in nowrap span if date in appropriate format
    -- COinS metadata (see <http://ocoins.info/>) for automated parsing of citation information.
    if (sepc ~= ".") then retrv_text = retrv_text:lower() end -- if 'citation', lower case
    -- handle the oddity that is cite encyclopedia and {{citation |encyclopedia=something}}. Here we presume that
    AccessDate = substitute (retrv_text, AccessDate); -- add retrieved text
    -- when Periodical, Title, and Chapter are all set, then Periodical is the book (encyclopedia) title, Title
    -- neither of these work; don't know why; it seems that substitute() isn't being called
    -- is the article title, and Chapter is a section within the article. So, we remap
    AccessDate = substitute (cfg.presentation['accessdate'], {sepc, AccessDate}); -- allow editors to hide accessdates
    end
    if is_set(ID) then ID = sepc .." ".. ID; end
    local coins_chapter = Chapter; -- default assuming that remapping not required
      if "thesis" == config.CitationClass and is_set(Docket) then
    local coins_title = Title; -- et tu
    ID = sepc .." Docket ".. Docket .. ID;
    if 'encyclopaedia' == config.CitationClass or ('citation' == config.CitationClass and utilities.is_set (Encyclopedia)) then
    if utilities.is_set (Chapter) and utilities.is_set (Title) and utilities.is_set (Periodical) then -- if all are used then
    coins_chapter = Title; -- remap
    coins_title = Periodical;
    end
    end
    end
      if "report" == config.CitationClass and is_set(Docket) then -- for cite report when |docket= is set
    local coins_author = a; -- default for coins rft.au
    ID = sepc .. ' ' .. Docket; -- overwrite ID even if |id= is set
    if 0 < #c then -- but if contributor list
    coins_author = c; -- use that instead
    end
    end
    local QuotePage = A['QuotePage'];
    local QuotePages = hyphen_to_dash (A['QuotePages']);


    ID_list = build_id_list( ID_list, {DoiBroken = DoiBroken, ASINTLD = ASINTLD, IgnoreISBN = IgnoreISBN, Embargo=Embargo, Class = Class} );
    -- this is the function call to COinS()
    local OCinSoutput = metadata.COinS({
    ['Periodical'] = utilities.strip_apostrophe_markup (Periodical), -- no markup in the metadata
    ['Encyclopedia'] = Encyclopedia, -- just a flag; content ignored by ~/COinS
    ['Chapter'] = metadata.make_coins_title (coins_chapter, ScriptChapter), -- Chapter and ScriptChapter stripped of bold / italic wiki-markup
    ['Degree'] = Degree; -- cite thesis only
    ['Title'] = metadata.make_coins_title (coins_title, ScriptTitle), -- Title and ScriptTitle stripped of bold / italic wiki-markup
    ['PublicationPlace'] = PublicationPlace,
    ['Date'] = COinS_date.rftdate, -- COinS_date has correctly formatted date if Date is valid;
    ['Season'] = COinS_date.rftssn,
    ['Quarter'] = COinS_date.rftquarter,
    ['Chron'] = COinS_date.rftchron or (not COinS_date.rftdate and Date) or '', -- chron but if not set and invalid date format use Date; keep this last bit?
    ['Series'] = Series,
    ['Volume'] = Volume,
    ['Issue'] = Issue,
    ['Pages'] = coins_pages or metadata.get_coins_pages (first_set ({Sheet, Sheets, Page, Pages, At, QuotePage, QuotePages}, 7)), -- pages stripped of external links
    ['Edition'] = Edition,
    ['PublisherName'] = PublisherName or Newsgroup, -- any apostrophe markup already removed from PublisherName
    ['URL'] = first_set ({ChapterURL, URL}, 2),
    ['Authors'] = coins_author,
    ['ID_list'] = ID_list_coins,
    ['RawPage'] = this_page.prefixedText,
    }, config.CitationClass);


    if is_set(URL) then
    -- Account for the oddities that are {{cite arxiv}}, {{cite biorxiv}}, {{cite citeseerx}}, and {{cite ssrn}} AFTER generation of COinS data.
    URL = " " .. external_link( URL, nil, URLorigin );
    if utilities.in_array (config.CitationClass, whitelist.preprint_template_list) then -- we have set rft.jtitle in COinS to arXiv, bioRxiv, CiteSeerX, or ssrn now unset so it isn't displayed
    Periodical = ''; -- periodical not allowed in these templates; if article has been published, use cite journal
    end
    end


    if is_set(Quote) then
    -- special case for cite newsgroup.  Do this after COinS because we are modifying Publishername to include some static text
    if Quote:sub(1,1) == '"' and Quote:sub(-1,-1) == '"' then
    if 'newsgroup' == config.CitationClass and utilities.is_set (Newsgroup) then
    Quote = Quote:sub(2,-2);
    PublisherName = utilities.substitute (cfg.messages['newsgroup'], external_link( 'news:' .. Newsgroup, Newsgroup, Newsgroup_origin, nil ));
    end
    Quote = sepc .." " .. wrap_style ('quoted-text', Quote ); -- wrap in <q>...</q> tags
    PostScript = ""; -- CS1 does not supply terminal punctuation when |quote= is set
    end
    end
    local Editors;
    local EditorCount; -- used only for choosing {ed.) or (eds.) annotation at end of editor name-list
    local Contributors; -- assembled contributors name list
    local contributor_etal;
    local Translators; -- assembled translators name list
    local translator_etal;
    local t = {}; -- translators list from |translator-lastn= / translator-firstn= pairs
    t = extract_names (args, 'TranslatorList'); -- fetch translator list from |translatorn= / |translator-lastn=, -firstn=, -linkn=, -maskn=
    local Interviewers;
    local interviewers_list = {};
    interviewers_list = extract_names (args, 'InterviewerList'); -- process preferred interviewers parameters
    local interviewer_etal;
    local Archived
    -- Now perform various field substitutions.
    if is_set(ArchiveURL) then
    -- We also add leading spaces and surrounding markup and punctuation to the
    if not is_set(ArchiveDate) then
    -- various parts of the citation, but only when they are non-nil.
    ArchiveDate = set_error('archive_missing_date');
    do
    local last_first_list;
    local control = {
    format = NameListStyle, -- empty string or 'vanc'
    maximum = nil, -- as if display-authors or display-editors not set
    mode = Mode
    };
     
    do -- do editor name list first because the now unsupported coauthors used to modify control table
    control.maximum , editor_etal = get_display_names (A['DisplayEditors'], #e, 'editors', editor_etal, A:ORIGIN ('DisplayEditors'));
    Editors, EditorCount = list_people (control, e, editor_etal);
     
    if 1 == EditorCount and (true == editor_etal or 1 < #e) then -- only one editor displayed but includes etal then
    EditorCount = 2; -- spoof to display (eds.) annotation
    end
    end
    do -- now do interviewers
    control.maximum, interviewer_etal = get_display_names (A['DisplayInterviewers'], #interviewers_list, 'interviewers', interviewer_etal, A:ORIGIN ('DisplayInterviewers'));
    Interviewers = list_people (control, interviewers_list, interviewer_etal);
    end
    end
    if "no" == DeadURL then
    do -- now do translators
    local arch_text = cfg.messages['archived'];
    control.maximum, translator_etal = get_display_names (A['DisplayTranslators'], #t, 'translators', translator_etal, A:ORIGIN ('DisplayTranslators'));
    if sepc ~= "." then arch_text = arch_text:lower() end
    Translators = list_people (control, t, translator_etal);
    Archived = sepc .. " " .. substitute( cfg.messages['archived-not-dead'],
    end
    { external_link( ArchiveURL, arch_text ) .. ArchiveFormat, ArchiveDate } );
    do -- now do contributors
    if not is_set(OriginalURL) then
    control.maximum, contributor_etal = get_display_names (A['DisplayContributors'], #c, 'contributors', contributor_etal, A:ORIGIN ('DisplayContributors'));
    Archived = Archived .. " " .. set_error('archive_missing_url');  
    Contributors = list_people (control, c, contributor_etal);
    end
    do -- now do authors
    control.maximum, author_etal = get_display_names (A['DisplayAuthors'], #a, 'authors', author_etal, A:ORIGIN ('DisplayAuthors'));
     
    last_first_list = list_people (control, a, author_etal);
     
    if utilities.is_set (Authors) then
    Authors, author_etal = name_has_etal (Authors, author_etal, false, 'authors'); -- find and remove variations on et al.
    if author_etal then
    Authors = Authors .. ' ' .. cfg.messages['et al']; -- add et al. to authors parameter
    end
    else
    Authors = last_first_list; -- either an author name list or an empty string
    end
    end
    elseif is_set(OriginalURL) then -- DeadURL is empty, 'yes', 'true', 'y', 'unfit', 'usurped'
    end -- end of do
    local arch_text = cfg.messages['archived-dead'];
    if sepc ~= "." then arch_text = arch_text:lower() end
    if utilities.is_set (Authors) and utilities.is_set (Collaboration) then
    -- if 'usurped' == DeadURL then -- when original has unsuitable content do not link
    Authors = Authors .. ' (' .. Collaboration .. ')'; -- add collaboration after et al.
    if in_array (DeadURL, {'unfit', 'usurped'}) then
    Archived = sepc .. " " .. 'Archived from the original on ' .. ArchiveDate; -- format already styled
    else -- DeadURL is empty, 'yes', 'true', or 'y'
    Archived = sepc .. " " .. substitute( arch_text,
    { external_link( OriginalURL, cfg.messages['original'] ) .. OriginalFormat, ArchiveDate } ); -- format already styled
    end
    else
    local arch_text = cfg.messages['archived-missing'];
    if sepc ~= "." then arch_text = arch_text:lower() end
    Archived = sepc .. " " .. substitute( arch_text,
    { set_error('archive_missing_url'), ArchiveDate } );
    end
    end
    elseif is_set (ArchiveFormat) then
     
    Archived = ArchiveFormat; -- if set and ArchiveURL not set ArchiveFormat has error message
    else
    Archived = ""
    end
    end
     
    local Lay = '';
    local ConferenceFormat = A['ConferenceFormat'];
    if is_set(LayURL) then
    local ConferenceURL = A['ConferenceURL'];
    if is_set(LayDate) then LayDate = " (" .. LayDate .. ")" end
    ConferenceFormat = style_format (ConferenceFormat, ConferenceURL, 'conference-format', 'conference-url');
    if is_set(LaySource) then
    Format = style_format (Format, URL, 'format', 'url');
    LaySource = " &ndash; ''" .. safe_for_italics(LaySource) .. "''";
     
    else
    -- special case for chapter format so no error message or cat when chapter not supported
    LaySource = "";
    if not (utilities.in_array (config.CitationClass, {'web', 'news', 'journal', 'magazine', 'pressrelease', 'podcast', 'newsgroup', 'arxiv', 'biorxiv', 'citeseerx', 'ssrn'}) or
    end
    ('citation' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and not utilities.is_set (Encyclopedia))) then
    if sepc == '.' then
    ChapterFormat = style_format (ChapterFormat, ChapterURL, 'chapter-format', 'chapter-url');
    Lay = sepc .. " " .. external_link( LayURL, cfg.messages['lay summary'] ) .. LayFormat .. LaySource .. LayDate
    else
    Lay = sepc .. " " .. external_link( LayURL, cfg.messages['lay summary']:lower() ) .. LayFormat .. LaySource .. LayDate
    end
    elseif is_set (LayFormat) then -- Test if |lay-format= is given without giving a |lay-url=
    Lay = sepc .. LayFormat; -- if set and LayURL not set, then LayFormat has error message
    end
    end


    if is_set(Transcript) then
    if not utilities.is_set (URL) then
    if is_set(TranscriptURL) then
    if utilities.in_array (config.CitationClass, {"web", "podcast", "mailinglist"}) or -- |url= required for cite web, cite podcast, and cite mailinglist
    Transcript = external_link( TranscriptURL, Transcript );
    ('citation' == config.CitationClass and ('website' == Periodical_origin or 'script-website' == ScriptPeriodical_origin)) then -- and required for {{citation}} with |website= or |script-website=
    table.insert( z.message_tail, { utilities.set_message ( 'err_cite_web_url', {}, true ) } );
    end
    -- do we have |accessdate= without either |url= or |chapter-url=?
    if utilities.is_set (AccessDate) and not utilities.is_set (ChapterURL) then -- ChapterURL may be set when URL is not set;
    table.insert( z.message_tail, { utilities.set_message ( 'err_accessdate_missing_url', {}, true ) } );
    AccessDate = '';
    end
    end
    Transcript = sepc .. ' ' .. Transcript .. TranscriptFormat;
    elseif is_set(TranscriptURL) then
    Transcript = external_link( TranscriptURL, nil, TranscriptURLorigin );
    end
    end


    local Publisher;
    local UrlStatus = is_valid_parameter_value (A['UrlStatus'], A:ORIGIN('UrlStatus'), cfg.keywords_lists['url-status'], '');
    if is_set(Periodical) and
    local OriginalURL
    not in_array(config.CitationClass, {"encyclopaedia","web","pressrelease","podcast"}) then
    local OriginalURL_origin
    if is_set(PublisherName) then
    local OriginalFormat
    if is_set(PublicationPlace) then
    local OriginalAccess;
    Publisher = PublicationPlace .. ": " .. PublisherName;
    UrlStatus = UrlStatus:lower(); -- used later when assembling archived text
    else
    if utilities.is_set ( ArchiveURL ) then
    Publisher = PublisherName;
    if utilities.is_set (ChapterURL) then -- if chapter-url= is set apply archive url to it
    OriginalURL = ChapterURL; -- save copy of source chapter's url for archive text
    OriginalURL_origin = ChapterURL_origin; -- name of |chapter-url= parameter for error messages
    OriginalFormat = ChapterFormat; -- and original |chapter-format=
     
    if 'live' ~= UrlStatus then
    ChapterURL = ArchiveURL -- swap-in the archive's URL
    ChapterURL_origin = A:ORIGIN('ArchiveURL') -- name of |archive-url= parameter for error messages
    ChapterFormat = ArchiveFormat or ''; -- swap in archive's format
    ChapterUrlAccess = nil; -- restricted access levels do not make sense for archived URLs
    end
    end
    elseif is_set(PublicationPlace) then
    elseif utilities.is_set (URL) then
    Publisher= PublicationPlace;
    OriginalURL = URL; -- save copy of original source URL
    else
    OriginalURL_origin = URL_origin; -- name of URL parameter for error messages
    Publisher = "";
    OriginalFormat = Format; -- and original |format=
    end
    OriginalAccess = UrlAccess;
    if is_set(PublicationDate) then
     
    if is_set(Publisher) then
    if 'live' ~= UrlStatus then -- if URL set then |archive-url= applies to it
    Publisher = Publisher .. ", " .. wrap_msg ('published', PublicationDate);
    URL = ArchiveURL -- swap-in the archive's URL
    else
    URL_origin = A:ORIGIN('ArchiveURL') -- name of archive URL parameter for error messages
    Publisher = PublicationDate;
    Format = ArchiveFormat or ''; -- swap in archive's format
    UrlAccess = nil; -- restricted access levels do not make sense for archived URLs
    end
    end
    end
     
    if utilities.in_array (config.CitationClass, {'web', 'news', 'journal', 'magazine', 'pressrelease', 'podcast', 'newsgroup', 'arxiv', 'biorxiv', 'citeseerx', 'ssrn'}) or -- if any of the 'periodical' cites except encyclopedia
    ('citation' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and not utilities.is_set (Encyclopedia)) then
    local chap_param;
    if utilities.is_set (Chapter) then -- get a parameter name from one of these chapter related meta-parameters
    chap_param = A:ORIGIN ('Chapter')
    elseif utilities.is_set (TransChapter) then
    chap_param = A:ORIGIN ('TransChapter')
    elseif utilities.is_set (ChapterURL) then
    chap_param = A:ORIGIN ('ChapterURL')
    elseif utilities.is_set (ScriptChapter) then
    chap_param = ScriptChapter_origin;
    else utilities.is_set (ChapterFormat)
    chap_param = A:ORIGIN ('ChapterFormat')
    end
     
    if utilities.is_set (chap_param) then -- if we found one
    table.insert( z.message_tail, { utilities.set_message ( 'err_chapter_ignored', {chap_param}, true ) } ); -- add error message
    Chapter = ''; -- and set them to empty string to be safe with concatenation
    TransChapter = '';
    ChapterURL = '';
    ScriptChapter = '';
    ChapterFormat = '';
    end
    else -- otherwise, format chapter / article title
    local no_quotes = false; -- default assume that we will be quoting the chapter parameter value
    if utilities.is_set (Contribution) and 0 < #c then -- if this is a contribution with contributor(s)
    if utilities.in_array (Contribution:lower(), cfg.keywords_lists.contribution) then -- and a generic contribution title
    no_quotes = true; -- then render it unquoted
    end
    end
    end
    end
    if is_set(Publisher) then
     
    Publisher = " (" .. Publisher .. ")";
    Chapter = format_chapter_title (ScriptChapter, ScriptChapter_origin, Chapter, Chapter_origin, TransChapter, TransChapter_origin, ChapterURL, ChapterURL_origin, no_quotes, ChapterUrlAccess); -- Contribution is also in Chapter
    if utilities.is_set (Chapter) then
    Chapter = Chapter .. ChapterFormat ;
    if 'map' == config.CitationClass and utilities.is_set (TitleType) then
    Chapter = Chapter .. ' ' .. TitleType; -- map annotation here; not after title
    end
    Chapter = Chapter .. sepc .. ' ';
    elseif utilities.is_set (ChapterFormat) then -- |chapter= not set but |chapter-format= is so ...
    Chapter = ChapterFormat .. sepc .. ' '; -- ... ChapterFormat has error message, we want to see it
    end
    end
    else
    end
    if is_set(PublicationDate) then
     
    PublicationDate = " (" .. wrap_msg ('published', PublicationDate) .. ")";
    -- Format main title
    local plain_title = false;
    local accept_title;
    Title, accept_title = utilities.has_accept_as_written (Title, true); -- remove accept-this-as-written markup when it wraps all of <Title>
    if accept_title and ('' == Title) then -- only support forced empty for now "(())"
    Title = cfg.messages['notitle']; -- replace by predefined "No title" message
    -- TODO: utilities.set_message ( 'err_redundant_parameters', ...); -- issue proper error message instead of muting
    ScriptTitle = ''; -- just mute for now
    TransTitle = ''; -- just mute for now
    plain_title = true; -- suppress text decoration for descriptive title
    utilities.set_message ('maint_untitled'); -- add maint cat
    end
     
    if not accept_title then -- <Title> not wrapped in accept-as-written markup
    if '...' == Title:sub (-3) then -- if ellipsis is the last three characters of |title=
    Title = Title:gsub ('(%.%.%.)%.+$', '%1'); -- limit the number of dots to three
    elseif not mw.ustring.find (Title, '%.%s*%a%.$') and -- end of title is not a 'dot-(optional space-)letter-dot' initialism ...
    not mw.ustring.find (Title, '%s+%a%.$') then -- ...and not a 'space-letter-dot' initial (''Allium canadense'' L.)
    Title = mw.ustring.gsub(Title, '%' .. sepc .. '$', ''); -- remove any trailing separator character; sepc and ms.ustring() here for languages that use multibyte separator characters
    end
    end
    if is_set(PublisherName) then
     
    if is_set(PublicationPlace) then
    if utilities.is_set (ArchiveURL) and is_archived_copy (Title) then
    Publisher = sepc .. " " .. PublicationPlace .. ": " .. PublisherName .. PublicationDate;
    utilities.set_message ('maint_archived_copy'); -- add maintenance category before we modify the content of Title
    else
    Publisher = sepc .. " " .. PublisherName .. PublicationDate; 
    end
    elseif is_set(PublicationPlace) then
    Publisher= sepc .. " " .. PublicationPlace .. PublicationDate;
    else
    Publisher = PublicationDate;
    end
    end
    end
     
    if is_generic_title (Title) then
    -- Several of the above rely upon detecting this as nil, so do it last.
    table.insert (z.message_tail, {utilities.set_message ( 'err_generic_title', {}, true ) } ); -- set an error message
    if is_set(Periodical) then
    if is_set(Title) or is_set(TitleNote) then  
    Periodical = sepc .. " " .. wrap_style ('italic-title', Periodical)  
    else
    Periodical = wrap_style ('italic-title', Periodical)
    end
    end
    end
    end


    --[[
    if (not plain_title) and (utilities.in_array (config.CitationClass, {'web', 'news', 'journal', 'magazine', 'pressrelease', 'podcast', 'newsgroup', 'mailinglist', 'interview', 'arxiv', 'biorxiv', 'citeseerx', 'ssrn'}) or
    Handle the oddity that is cite speech. This code overrides whatever may be the value assigned to TitleNote (through |department=) and forces it to be " (Speech)" so that
    ('citation' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and not utilities.is_set (Encyclopedia)) or
    the annotation directly follows the |title= parameter value in the citation rather than the |event= parameter value (if provided).
    ('map' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)))) then -- special case for cite map when the map is in a periodical treat as an article
    ]]
    Title = kern_quotes (Title); -- if necessary, separate title's leading and trailing quote marks from module provided quote marks
    if "speech" == config.CitationClass then -- cite speech only
    Title = utilities.wrap_style ('quoted-title', Title);
    TitleNote = " (Speech)"; -- annotate the citation
    Title = script_concatenate (Title, ScriptTitle, 'script-title'); -- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped
    if is_set (Periodical) then -- if Periodical, perhaps because of an included |website= or |journal= parameter
    TransTitle = utilities.wrap_style ('trans-quoted-title', TransTitle );
    if is_set (Conference) then -- and if |event= is set
    elseif plain_title or ('report' == config.CitationClass) then -- no styling for cite report and descriptive titles (otherwise same as above)
    Conference = Conference .. sepc .. " "; -- then add appropriate punctuation to the end of the Conference variable before rendering
    Title = script_concatenate (Title, ScriptTitle, 'script-title'); -- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped
    end
    TransTitle = utilities.wrap_style ('trans-quoted-title', TransTitle ); -- for cite report, use this form for trans-title
    end
    else
    Title = utilities.wrap_style ('italic-title', Title);
    Title = script_concatenate (Title, ScriptTitle, 'script-title'); -- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped
    TransTitle = utilities.wrap_style ('trans-italic-title', TransTitle);
    end
    end


    -- Piece all bits together at last. Here, all should be non-nil.
    local TransError = "";
    -- We build things this way because it is more efficient in LUA
    if utilities.is_set (TransTitle) then
    -- not to keep reassigning to the same string variable over and over.
    if utilities.is_set (Title) then
    TransTitle = " " .. TransTitle;
    else
    TransError = " " .. utilities.set_message ( 'err_trans_missing_title', {'title'} );
    end
    end


    local tcommon
    if utilities.is_set (Title) then -- TODO: is this the right place to be making Wikisource URLs?
    if in_array(config.CitationClass, {"journal","citation"}) and is_set(Periodical) then
    if utilities.is_set (TitleLink) and utilities.is_set (URL) then
    if is_set(Others) then Others = Others .. sepc .. " " end
    table.insert( z.message_tail, { utilities.set_message ( 'err_wikilink_in_url', {}, true ) } ); -- set an error message because we can't have both
    tcommon = safe_join( {Others, Title, TitleNote, Conference, Periodical, Format, TitleType, Series,
    TitleLink = ''; -- unset
    Language, Edition, Publisher, Agency, Volume, Issue}, sepc );
    elseif 'map' == config.CitationClass then -- special cases for cite map
    if is_set (Chapter) then -- map in a book; TitleType is part of Chapter
    tcommon = safe_join( {Title, Format, Edition, Scale, Series, Language, Cartography, Others, Publisher, Volume}, sepc );
    elseif is_set (Periodical) then -- map in a periodical
    tcommon = safe_join( {Title, TitleType, Format, Periodical, Scale, Series, Language, Cartography, Others, Publisher, Volume, Issue}, sepc );
    else -- a sheet or stand-alone map
    tcommon = safe_join( {Title, TitleType, Format, Edition, Scale, Series, Language, Cartography, Others, Publisher}, sepc );
    end
    end
    elseif 'episode' == config.CitationClass then -- special case for cite episode
    tcommon = safe_join( {Title, TitleNote, TitleType, Series, Transcript, Language, Edition, Publisher}, sepc );
    else -- all other CS1 templates
    tcommon = safe_join( {Title, TitleNote, Conference, Periodical, Format, TitleType, Series, Language,
    Volume, Issue, Others, Edition, Publisher, Agency}, sepc );
    end
    if #ID_list > 0 then
    if not utilities.is_set (TitleLink) and utilities.is_set (URL) then
    ID_list = safe_join( { sepc .. " ", table.concat( ID_list, sepc .. " " ), ID }, sepc );
    Title = external_link (URL, Title, URL_origin, UrlAccess) .. TransTitle .. TransError .. Format;
    URL = ''; -- unset these because no longer needed
    Format = "";
    elseif utilities.is_set (TitleLink) and not utilities.is_set (URL) then
    local ws_url;
    ws_url = wikisource_url_make (TitleLink); -- ignore ws_label return; not used here
    if ws_url then
    Title = external_link (ws_url, Title .. '&nbsp;', 'ws link in title-link'); -- space char after Title to move icon away from italic text; TODO: a better way to do this?
    Title = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], TitleLink, Title});
    Title = Title .. TransTitle .. TransError;
    else
    Title = utilities.make_wikilink (TitleLink, Title) .. TransTitle .. TransError;
    end
    else
    local ws_url, ws_label, L; -- Title has italic or quote markup by the time we get here which causes is_wikilink() to return 0 (not a wikilink)
    ws_url, ws_label, L = wikisource_url_make (Title:gsub('^[\'"]*(.-)[\'"]*$', '%1')); -- make ws URL from |title= interwiki link (strip italic or quote markup); link portion L becomes tooltip label
    if ws_url then
    Title = Title:gsub ('%b[]', ws_label); -- replace interwiki link with ws_label to retain markup
    Title = external_link (ws_url, Title .. '&nbsp;', 'ws link in title'); -- space char after Title to move icon away from italic text; TODO: a better way to do this?
    Title = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, Title});
    Title = Title .. TransTitle .. TransError;
    else
    Title = Title .. TransTitle .. TransError;
    end
    end
    else
    else
    ID_list = ID;
    Title = TransTitle .. TransError;
    end
    end
     
    local idcommon = safe_join( { ID_list, URL, Archived, AccessDate, Via, SubscriptionRequired, Lay, Quote }, sepc );
    if utilities.is_set (Place) then
    local text;
    Place = " " .. wrap_msg ('written', Place, use_lowercase) .. sepc .. " ";
    local pgtext = Position .. Sheet .. Page .. Pages .. At;
    end
     
    if is_set(Authors) then
    local ConferenceURL_origin = A:ORIGIN('ConferenceURL'); -- get name of parameter that holds ConferenceURL
    if is_set(Coauthors) then
    if utilities.is_set (Conference) then
    local sep = '; ';
    if utilities.is_set (ConferenceURL) then
    if 'vanc' == NameListFormat then
    Conference = external_link( ConferenceURL, Conference, ConferenceURL_origin, nil );
    sep = ', ';
    end
    Conference = sepc .. " " .. Conference .. ConferenceFormat;
    elseif utilities.is_set (ConferenceURL) then
    Conference = sepc .. " " .. external_link( ConferenceURL, nil, ConferenceURL_origin, nil );
    end
     
    local Position = '';
    if not utilities.is_set (Position) then
    local Minutes = A['Minutes'];
    local Time = A['Time'];
     
    if utilities.is_set (Minutes) then
    if utilities.is_set (Time) then
    table.insert( z.message_tail, { utilities.set_message ( 'err_redundant_parameters', {utilities.wrap_style ('parameter', 'minutes') .. ' and ' .. utilities.wrap_style ('parameter', 'time')}, true ) } );
    end
    end
    Authors = Authors .. sep .. Coauthors;
    Position = " " .. Minutes .. " " .. cfg.messages['minutes'];
    end
    if is_set(Date) then
    Date = " ("..Date..")" .. OrigYear .. sepc .. " "
    elseif string.sub(Authors,-1,-1) == sepc then
    Authors = Authors .. " "
    else
    else
    Authors = Authors .. sepc .. " "
    if utilities.is_set (Time) then
    end
    local TimeCaption = A['TimeCaption']
    if is_set(Editors) then
    if not utilities.is_set (TimeCaption) then
    local in_text = " ";
    TimeCaption = cfg.messages['event'];
    local post_text = "";
    if sepc ~= '.' then
    if is_set(Chapter) then
    TimeCaption = TimeCaption:lower();
    in_text = in_text .. cfg.messages['in'] .. " "
    end
    else
    if EditorCount <= 1 then
    post_text = ", " .. cfg.messages['editor'];
    else
    post_text = ", " .. cfg.messages['editors'];
    end
    end
    end
    Position = " " .. TimeCaption .. " " .. Time;
    if (sepc ~= '.') then in_text = in_text:lower() end
    Editors = in_text .. Editors .. post_text;
    if (string.sub(Editors,-1,-1) == sepc) or (string.sub(Editors,-3,-1) == sepc .. ']]') then -- if last editor name ends with sepc char
    Editors = Editors .. " "; -- don't add another
    else
    Editors = Editors .. sepc .. " " -- otherwise terninate the editor list
    end
    end
    end
    end
    text = safe_join( {Authors, Date, Chapter, Place, Editors, tcommon }, sepc );
    else
    text = safe_join( {text, pgtext, idcommon}, sepc );
    Position = " " .. Position;
    elseif is_set(Editors) then
    At = '';
    if is_set(Date) then
    if EditorCount <= 1 then
    Editors = Editors .. ", " .. cfg.messages['editor'];
    else
    Editors = Editors .. ", " .. cfg.messages['editors'];
    end
    Date = " (" .. Date ..")" .. OrigYear .. sepc .. " "
    else
    if EditorCount <= 1 then
    Editors = Editors .. " (" .. cfg.messages['editor'] .. ")" .. sepc .. " "
    else
    Editors = Editors .. " (" .. cfg.messages['editors'] .. ")" .. sepc .. " "
    end
    end
    text = safe_join( {Editors, Date, Chapter, Place, tcommon}, sepc );
    text = safe_join( {text, pgtext, idcommon}, sepc );
    else
    if is_set(Date) then
    if ( string.sub(tcommon,-1,-1) ~= sepc )
      then Date = sepc .." " .. Date .. OrigYear
      else Date = " " .. Date .. OrigYear
    end
    end
    if config.CitationClass=="journal" and is_set(Periodical) then
    text = safe_join( {Chapter, Place, tcommon}, sepc );
    text = safe_join( {text, pgtext, Date, idcommon}, sepc );
    else
    text = safe_join( {Chapter, Place, tcommon, Date}, sepc );
    text = safe_join( {text, pgtext, idcommon}, sepc );
    end
    end
    end
    if is_set(PostScript) and PostScript ~= sepc then
    text = safe_join( {text, sepc}, sepc );  --Deals with italics, spaces, etc.
    text = text:sub(1,-sepc:len()-1);
    end
    text = safe_join( {text, PostScript}, sepc );


    -- Now enclose the whole thing in a <cite/> element
    Page, Pages, Sheet, Sheets = format_pages_sheets (Page, Pages, Sheet, Sheets, config.CitationClass, Periodical_origin, sepc, NoPP, use_lowercase);
    local options = {};
     
    At = utilities.is_set (At) and (sepc .. " " .. At) or "";
    if is_set(config.CitationClass) and config.CitationClass ~= "citation" then
    Position = utilities.is_set (Position) and (sepc .. " " .. Position) or "";
    options.class = config.CitationClass;
    if config.CitationClass == 'map' then
    options.class = "citation " .. config.CitationClass; -- class=citation required for blue highlight when used with |ref=
    local Sections = A['Sections']; -- Section (singular) is an alias of Chapter so set earlier
    else
    local Inset = A['Inset'];
    options.class = "citation";
    if utilities.is_set ( Inset ) then
    Inset = sepc .. " " .. wrap_msg ('inset', Inset, use_lowercase);
    end
     
    if utilities.is_set ( Sections ) then
    Section = sepc .. " " .. wrap_msg ('sections', Sections, use_lowercase);
    elseif utilities.is_set ( Section ) then
    Section = sepc .. " " .. wrap_msg ('section', Section, use_lowercase);
    end
    At = At .. Inset .. Section;
    end
     
    local Others = A['Others'];
    if utilities.is_set (Others) and 0 == #a and 0 == #e then -- add maint cat when |others= has value and used without |author=, |editor=
    if config.CitationClass == "AV-media-notes"
    or config.CitationClass == "audio-visual" then -- special maint for AV/M which has a lot of 'false' positives right now
    utilities.set_message ('maint_others_avm')
    else
    utilities.set_message ('maint_others');
    end
    end
    end
    Others = utilities.is_set (Others) and (sepc .. " " .. Others) or "";
    if is_set(Ref) and Ref:lower() ~= "none" then
    if utilities.is_set (Translators) then
    local id = Ref
    Others = safe_join ({sepc .. ' ', wrap_msg ('translated', Translators, use_lowercase), Others}, sepc);
    if ( "harv" == Ref ) then
    local names = {} --table of last names & year
    if #a > 0 then
    for i,v in ipairs(a) do
    names[i] = v.last
    if i == 4 then break end
    end
    elseif #e > 0 then
    for i,v in ipairs(e) do
    names[i] = v.last
    if i == 4 then break end
    end
    end
    names[ #names + 1 ] = first_set(Year, anchor_year); -- Year first for legacy citations and for YMD dates that require disambiguation
    id = anchor_id(names)
    end
    options.id = id;
    end
    end
    if utilities.is_set (Interviewers) then
    if string.len(text:gsub("<span[^>/]*>.-</span>", ""):gsub("%b<>","")) <= 2 then
    Others = safe_join ({sepc .. ' ', wrap_msg ('interview', Interviewers, use_lowercase), Others}, sepc);
    z.error_categories = {};
    text = set_error('empty_citation');
    z.message_tail = {};
    end
    end
    if is_set(options.id) then  
    local TitleNote = A['TitleNote'];
    text = '<cite id="' .. mw.uri.anchorEncode(options.id) ..'" class="' .. mw.text.nowiki(options.class) .. '">' .. text .. "</cite>";
    TitleNote = utilities.is_set (TitleNote) and (sepc .. " " .. TitleNote) or "";
    if utilities.is_set (Edition) then
    if Edition:match ('%f[%a][Ee]d%n?%.?$') or Edition:match ('%f[%a][Ee]dition$') then -- Ed, ed, Ed., ed., Edn, edn, Edn., edn.
    table.insert( z.message_tail, { utilities.set_message ( 'err_extra_text_edition')}); -- add error
    end
    Edition = " " .. wrap_msg ('edition', Edition);
    else
    else
    text = '<cite class="' .. mw.text.nowiki(options.class) .. '">' .. text .. "</cite>";
    Edition = '';
    end
    end


    local empty_span = '<span style="display:none;">&nbsp;</span>';
    Series = utilities.is_set (Series) and wrap_msg ('series', {sepc, Series}) or ""; -- not the same as SeriesNum
    local Agency = A['Agency'];
    -- Note: Using display: none on then COinS span breaks some clients.
    Agency = utilities.is_set (Agency) and wrap_msg ('agency', {sepc, Agency}) or "";
    local OCinS = '<span title="' .. OCinSoutput .. '" class="Z3988">' .. empty_span .. '</span>';
    Volume = format_volume_issue (Volume, Issue, config.CitationClass, Periodical_origin, sepc, use_lowercase);
    text = text .. OCinS;
     
    if utilities.is_set (AccessDate) then
    local retrv_text = " " .. cfg.messages['retrieved']
     
    AccessDate = nowrap_date (AccessDate); -- wrap in nowrap span if date in appropriate format
    if (sepc ~= ".") then retrv_text = retrv_text:lower() end -- if mode is cs2, lower case
    AccessDate = utilities.substitute (retrv_text, AccessDate); -- add retrieved text
     
    AccessDate = utilities.substitute (cfg.presentation['accessdate'], {sepc, AccessDate}); -- allow editors to hide accessdates
    end
    if utilities.is_set (ID) then ID = sepc .. " " .. ID; end
    if #z.message_tail ~= 0 then
    local Docket = A['Docket'];
    text = text .. " ";
      if "thesis" == config.CitationClass and utilities.is_set (Docket) then
    for i,v in ipairs( z.message_tail ) do
    ID = sepc .. " Docket " .. Docket .. ID;
    if is_set(v[1]) then
    end
    if i == #z.message_tail then
      if "report" == config.CitationClass and utilities.is_set (Docket) then -- for cite report when |docket= is set
    text = text .. error_comment( v[1], v[2] );
    ID = sepc .. ' ' .. Docket; -- overwrite ID even if |id= is set
    else
    end
    text = text .. error_comment( v[1] .. "; ", v[2] );
     
    end
    if utilities.is_set (URL) then
    URL = " " .. external_link( URL, nil, URL_origin, UrlAccess );
    end
     
    local Quote = A['Quote'];
    local TransQuote = A['TransQuote'];
    local ScriptQuote = A['ScriptQuote'];
    if utilities.is_set (Quote) or utilities.is_set (TransQuote) or utilities.is_set (ScriptQuote) then
     
    if utilities.is_set (Quote) then
    if Quote:sub(1, 1) == '"' and Quote:sub(-1, -1) == '"' then -- if first and last characters of quote are quote marks
    Quote = Quote:sub(2, -2); -- strip them off
    end
    end
    end
    end
    end


    if #z.maintenance_cats ~= 0 then
    Quote = utilities.wrap_style ('quoted-text', Quote ); -- wrap in <q>...</q> tags
    text = text .. '<span class="citation-comment" style="display:none; color:#33aa33">';
    for _, v in ipairs( z.maintenance_cats ) do -- append maintenance categories
    text = text .. ' ' .. v .. ' ([[:Category:' .. v ..'|link]])';
    end
    text = text .. '</span>'; -- maintenance mesages (realy just the names of the categories for now)
    end
    no_tracking_cats = no_tracking_cats:lower();
    if utilities.is_set (ScriptQuote) then
    if in_array(no_tracking_cats, {"", "no", "false", "n"}) then
    Quote = script_concatenate (Quote, ScriptQuote, 'script-quote'); -- <bdi> tags, lang attribute, categorization, etc.; must be done after quote is wrapped
    for _, v in ipairs( z.error_categories ) do
    text = text .. '[[Category:' .. v ..']]';
    end
    end
    for _, v in ipairs( z.maintenance_cats ) do -- append maintenance categories
     
    text = text .. '[[Category:' .. v ..']]';
    if utilities.is_set (TransQuote) then
    if TransQuote:sub(1, 1) == '"' and TransQuote:sub(-1, -1) == '"' then -- if first and last characters of |trans-quote are quote marks
    TransQuote = TransQuote:sub(2, -2); -- strip them off
    end
    Quote = Quote .. " " .. utilities.wrap_style ('trans-quoted-title', TransQuote );
    end
    end
    for _, v in ipairs( z.properties_cats ) do -- append maintenance categories
     
    text = text .. '[[Category:' .. v ..']]';
    if utilities.is_set (QuotePage) or utilities.is_set (QuotePages) then -- add page prefix
    end
    local quote_prefix = '';
    end
    if utilities.is_set (QuotePage) then
    extra_text_in_page_check (QuotePage, 'quote-page'); -- add to maint cat if |quote-page= value begins with what looks like p., pp., etc.
    return text
    if not NoPP then
    end
    quote_prefix = utilities.substitute (cfg.messages['p-prefix'], {sepc, QuotePage}), '', '', '';
     
    else
    -- This is used by templates such as {{cite book}} to create the actual citation text.
    quote_prefix = utilities.substitute (cfg.messages['nopp'], {sepc, QuotePage}), '', '', '';
    function z.citation(frame)
    end
    local pframe = frame:getParent()
    elseif utilities.is_set (QuotePages) then
    local validation;
    extra_text_in_page_check (QuotePages, 'quote-pages'); -- add to maint cat if |quote-pages= value begins with what looks like p., pp., etc.
    if tonumber(QuotePages) ~= nil and not NoPP then -- if only digits, assume single page
    if nil ~= string.find (frame:getTitle(), 'sandbox', 1, true) then -- did the {{#invoke:}} use sandbox version?
    quote_prefix = utilities.substitute (cfg.messages['p-prefix'], {sepc, QuotePages}), '', '';
    cfg = mw.loadData ('Module:Citation/CS1/Configuration/sandbox'); -- load sandbox versions of Configuration and Whitelist and ...
    elseif not NoPP then
    whitelist = mw.loadData ('Module:Citation/CS1/Whitelist/sandbox');
    quote_prefix = utilities.substitute (cfg.messages['pp-prefix'], {sepc, QuotePages}), '', '';
    validation = require ('Module:Citation/CS1/Date_validation/sandbox'); -- ... sandbox version of date validation code
    else
     
    quote_prefix = utilities.substitute (cfg.messages['nopp'], {sepc, QuotePages}), '', '';
    else -- otherwise
    end
    cfg = mw.loadData ('Module:Citation/CS1/Configuration'); -- load live versions of Configuration and Whitelist and ...
    end
    whitelist = mw.loadData ('Module:Citation/CS1/Whitelist');
                           
    validation = require ('Module:Citation/CS1/Date_validation'); -- ... live version of date validation code
    Quote = quote_prefix .. ": " .. Quote;
    end
    else
     
    Quote = sepc .. " " .. Quote;
    dates = validation.dates; -- imported functions
    end
    year_date_check = validation.year_date_check;
     
     
    PostScript = ""; -- cs1|2 does not supply terminal punctuation when |quote= is set
    local args = {};
    end
    local suggestions = {};
    local error_text, error_state;
    -- We check length of PostScript here because it will have been nuked by
     
    -- the quote parameters. We'd otherwise emit a message even if there wasn't
    local config = {};
    -- a displayed postscript.
    for k, v in pairs( frame.args ) do
    -- TODO: Should the max size (1) be configurable?
    config[k] = v;
    -- TODO: Should we check a specific pattern?
    args[k] = v;  
    if utilities.is_set(PostScript) and mw.ustring.len(PostScript) > 1 then
    end
    utilities.set_message('maint_postscript')
     
    end
    local capture; -- the single supported capture when matching unknown parameters using patterns
    for k, v in pairs( pframe.args ) do
    local Archived
    if v ~= '' then
    if utilities.is_set (ArchiveURL) then
    if not validate( k ) then
    local arch_text;
    error_text = "";
    if not utilities.is_set (ArchiveDate) then
    if type( k ) ~= 'string' then
    ArchiveDate = utilities.set_message ('err_archive_missing_date');
    -- Exclude empty numbered parameters
    end
    if v:match("%S+") ~= nil then
    if "live" == UrlStatus then
    error_text, error_state = set_error( 'text_ignored', {v}, true );
    arch_text = cfg.messages['archived'];
    if sepc ~= "." then arch_text = arch_text:lower() end
    Archived = sepc .. " " .. utilities.substitute ( cfg.messages['archived-live'],
    { external_link( ArchiveURL, arch_text, A:ORIGIN('ArchiveURL'), nil ) .. ArchiveFormat, ArchiveDate } );
    if not utilities.is_set (OriginalURL) then
    Archived = Archived .. " " .. utilities.set_message ('err_archive_missing_url');  
    end
    elseif utilities.is_set (OriginalURL) then -- UrlStatus is empty, 'dead', 'unfit', 'usurped', 'bot: unknown'
    if utilities.in_array (UrlStatus, {'unfit', 'usurped', 'bot: unknown'}) then
    arch_text = cfg.messages['archived-unfit'];
    if sepc ~= "." then arch_text = arch_text:lower() end
    Archived = sepc .. " " .. arch_text .. ArchiveDate; -- format already styled
    if 'bot: unknown' == UrlStatus then
    utilities.set_message ('maint_bot_unknown'); -- and add a category if not already added
    else
    utilities.set_message ('maint_unfit'); -- and add a category if not already added
    end
    else -- UrlStatus is empty, 'dead'
    arch_text = cfg.messages['archived-dead'];
    if sepc ~= "." then arch_text = arch_text:lower() end
    Archived = sepc .. " " .. utilities.substitute ( arch_text,
    { external_link( OriginalURL, cfg.messages['original'], OriginalURL_origin, OriginalAccess ) .. OriginalFormat, ArchiveDate } ); -- format already styled
    end
    else -- OriginalUrl not set
    arch_text = cfg.messages['archived-missing'];
    if sepc ~= "." then arch_text = arch_text:lower() end
    Archived = sepc .. " " .. utilities.substitute ( arch_text,
    { utilities.set_message ('err_archive_missing_url'), ArchiveDate } );
    end
    elseif utilities.is_set (ArchiveFormat) then
    Archived = ArchiveFormat; -- if set and ArchiveURL not set ArchiveFormat has error message
    else
    Archived = ""
    end
    local Lay = '';
    local LaySource = A['LaySource'];
    local LayURL = A['LayURL'];
    local LayFormat = A['LayFormat'];
    LayFormat = style_format (LayFormat, LayURL, 'lay-format', 'lay-url');
    if utilities.is_set (LayURL) then
    if utilities.is_set (LayDate) then LayDate = " (" .. LayDate .. ")" end
    if utilities.is_set (LaySource) then
    LaySource = " &ndash; ''" .. utilities.safe_for_italics (LaySource) .. "''";
    else
    LaySource = "";
    end
    if sepc == '.' then
    Lay = sepc .. " " .. external_link( LayURL, cfg.messages['lay summary'], A:ORIGIN('LayURL'), nil ) .. LayFormat .. LaySource .. LayDate
    else
    Lay = sepc .. " " .. external_link( LayURL, cfg.messages['lay summary']:lower(), A:ORIGIN('LayURL'), nil ) .. LayFormat .. LaySource .. LayDate
    end
    elseif utilities.is_set (LayFormat) then -- Test if |lay-format= is given without giving a |lay-url=
    Lay = sepc .. LayFormat; -- if set and LayURL not set, then LayFormat has error message
    end
     
    local TranscriptURL = A['TranscriptURL']
    local TranscriptFormat = A['TranscriptFormat'];
    TranscriptFormat = style_format (TranscriptFormat, TranscriptURL, 'transcript-format', 'transcripturl');
    local Transcript = A['Transcript'];
    local TranscriptURL_origin = A:ORIGIN('TranscriptURL'); -- get name of parameter that holds TranscriptURL
    if utilities.is_set (Transcript) then
    if utilities.is_set (TranscriptURL) then
    Transcript = external_link( TranscriptURL, Transcript, TranscriptURL_origin, nil );
    end
    Transcript = sepc .. ' ' .. Transcript .. TranscriptFormat;
    elseif utilities.is_set (TranscriptURL) then
    Transcript = external_link( TranscriptURL, nil, TranscriptURL_origin, nil );
    end
     
    local Publisher;
    if utilities.is_set (PublicationDate) then
    PublicationDate = wrap_msg ('published', PublicationDate);
    end
    if utilities.is_set (PublisherName) then
    if utilities.is_set (PublicationPlace) then
    Publisher = sepc .. " " .. PublicationPlace .. ": " .. PublisherName .. PublicationDate;
    else
    Publisher = sepc .. " " .. PublisherName .. PublicationDate; 
    end
    elseif utilities.is_set (PublicationPlace) then
    Publisher= sepc .. " " .. PublicationPlace .. PublicationDate;
    else
    Publisher = PublicationDate;
    end
    local TransPeriodical =  A['TransPeriodical'];
    local TransPeriodical_origin =  A:ORIGIN ('TransPeriodical');
    -- Several of the above rely upon detecting this as nil, so do it last.
    if (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical) or utilities.is_set (TransPeriodical)) then
    if utilities.is_set (Title) or utilities.is_set (TitleNote) then
    Periodical = sepc .. " " .. format_periodical (ScriptPeriodical, ScriptPeriodical_origin, Periodical, TransPeriodical, TransPeriodical_origin);
    else
    Periodical = format_periodical (ScriptPeriodical, ScriptPeriodical_origin, Periodical, TransPeriodical, TransPeriodical_origin);
    end
    end
    local Language = A['Language'];
    if utilities.is_set (Language) then
    Language = language_parameter (Language); -- format, categories, name from ISO639-1, etc.
    else
    Language=''; -- language not specified so make sure this is an empty string;
    --[[ TODO: need to extract the wrap_msg from language_parameter
    so that we can solve parentheses bunching problem with Format/Language/TitleType
    ]]
    end
     
    --[[
    Handle the oddity that is cite speech.  This code overrides whatever may be the value assigned to TitleNote (through |department=) and forces it to be " (Speech)" so that
    the annotation directly follows the |title= parameter value in the citation rather than the |event= parameter value (if provided).
    ]]
    if "speech" == config.CitationClass then -- cite speech only
    TitleNote = " (Speech)"; -- annotate the citation
    if utilities.is_set (Periodical) then -- if Periodical, perhaps because of an included |website= or |journal= parameter
    if utilities.is_set (Conference) then -- and if |event= is set
    Conference = Conference .. sepc .. " "; -- then add appropriate punctuation to the end of the Conference variable before rendering
    end
    end
    end
     
    -- Piece all bits together at last.  Here, all should be non-nil.
    -- We build things this way because it is more efficient in LUA
    -- not to keep reassigning to the same string variable over and over.
     
    local tcommon;
    local tcommon2; -- used for book cite when |contributor= is set
    if utilities.in_array (config.CitationClass, {"journal", "citation"}) and utilities.is_set (Periodical) then
    if utilities.is_set (Others) then Others = safe_join ({Others, sepc .. " "}, sepc) end -- add terminal punctuation & space; check for dup sepc; TODO why do we need to do this here?
    tcommon = safe_join( {Others, Title, TitleNote, Conference, Periodical, Format, TitleType, Series, Language, Edition, Publisher, Agency, Volume}, sepc );
    elseif utilities.in_array (config.CitationClass, {"book", "citation"}) and not utilities.is_set (Periodical) then -- special cases for book cites
    if utilities.is_set (Contributors) then -- when we are citing foreword, preface, introduction, etc.
    tcommon = safe_join( {Title, TitleNote}, sepc ); -- author and other stuff will come after this and before tcommon2
    tcommon2 = safe_join( {Conference, Periodical, Format, TitleType, Series, Language, Volume, Others, Edition, Publisher, Agency}, sepc );
    else
    tcommon = safe_join( {Title, TitleNote, Conference, Periodical, Format, TitleType, Series, Language, Volume, Others, Edition, Publisher, Agency}, sepc );
    end
     
    elseif 'map' == config.CitationClass then -- special cases for cite map
    if utilities.is_set (Chapter) then -- map in a book; TitleType is part of Chapter
    tcommon = safe_join( {Title, Format, Edition, Scale, Series, Language, Cartography, Others, Publisher, Volume}, sepc );
    elseif utilities.is_set (Periodical) then -- map in a periodical
    tcommon = safe_join( {Title, TitleType, Format, Periodical, Scale, Series, Language, Cartography, Others, Publisher, Volume}, sepc );
    else -- a sheet or stand-alone map
    tcommon = safe_join( {Title, TitleType, Format, Edition, Scale, Series, Language, Cartography, Others, Publisher}, sepc );
    end
    elseif 'episode' == config.CitationClass then -- special case for cite episode
    tcommon = safe_join( {Title, TitleNote, TitleType, Series, Language, Edition, Publisher}, sepc );
     
    else -- all other CS1 templates
    tcommon = safe_join( {Title, TitleNote, Conference, Periodical, Format, TitleType, Series, Language,
    Volume, Others, Edition, Publisher, Agency}, sepc );
    end
    if #ID_list > 0 then
    ID_list = safe_join( { sepc .. " ",  table.concat( ID_list, sepc .. " " ), ID }, sepc );
    else
    ID_list = ID;
    end
    local Via = A['Via'];
    Via = utilities.is_set (Via) and  wrap_msg ('via', Via) or '';
    local idcommon;
    if 'audio-visual' == config.CitationClass or 'episode' == config.CitationClass then -- special case for cite AV media & cite episode position transcript
    idcommon = safe_join( { ID_list, URL, Archived, Transcript, AccessDate, Via, Lay, Quote }, sepc );
    else
    idcommon = safe_join( { ID_list, URL, Archived, AccessDate, Via, Lay, Quote }, sepc );
    end
    local text;
    local pgtext = Position .. Sheet .. Sheets .. Page .. Pages .. At;
     
    local OrigDate = A['OrigDate'];
    OrigDate = utilities.is_set (OrigDate) and wrap_msg ('origdate', OrigDate) or '';
    if utilities.is_set (Date) then
    if utilities.is_set (Authors) or utilities.is_set (Editors) then -- date follows authors or editors when authors not set
    Date = " (" .. Date .. ")" .. OrigDate .. sepc .. " "; -- in parentheses
    else -- neither of authors and editors set
    if (string.sub(tcommon, -1, -1) == sepc) then -- if the last character of tcommon is sepc
    Date = " " .. Date .. OrigDate; -- Date does not begin with sepc
    else
    Date = sepc .. " " .. Date .. OrigDate; -- Date begins with sepc
    end
    end
    end
    if utilities.is_set (Authors) then
    if (not utilities.is_set (Date)) then -- when date is set it's in parentheses; no Authors termination
    Authors = terminate_name_list (Authors, sepc); -- when no date, terminate with 0 or 1 sepc and a space
    end
    if utilities.is_set (Editors) then
    local in_text = " ";
    local post_text = "";
    if utilities.is_set (Chapter) and 0 == #c then
    in_text = in_text .. cfg.messages['in'] .. " "
    if (sepc ~= '.') then
    in_text = in_text:lower() -- lowercase for cs2
    end
    end
    if EditorCount <= 1 then
    post_text = " (" .. cfg.messages['editor'] .. ")"; -- be consistent with no-author, no-date case
    else
    post_text = " (" .. cfg.messages['editors'] .. ")";
    end
    Editors = terminate_name_list (in_text .. Editors .. post_text, sepc); -- terminate with 0 or 1 sepc and a space
    end
    if utilities.is_set (Contributors) then -- book cite and we're citing the intro, preface, etc.
    local by_text = sepc .. ' ' .. cfg.messages['by'] .. ' ';
    if (sepc ~= '.') then by_text = by_text:lower() end -- lowercase for cs2
    Authors = by_text .. Authors; -- author follows title so tweak it here
    if utilities.is_set (Editors) and utilities.is_set (Date) then -- when Editors make sure that Authors gets terminated
    Authors = terminate_name_list (Authors, sepc); -- terminate with 0 or 1 sepc and a space
    end
    if (not utilities.is_set (Date)) then -- when date is set it's in parentheses; no Contributors termination
    Contributors = terminate_name_list (Contributors, sepc); -- terminate with 0 or 1 sepc and a space
    end
    text = safe_join( {Contributors, Date, Chapter, tcommon, Authors, Place, Editors, tcommon2, pgtext, idcommon }, sepc );
    else
    text = safe_join( {Authors, Date, Chapter, Place, Editors, tcommon, pgtext, idcommon }, sepc );
    end
    elseif utilities.is_set (Editors) then
    if utilities.is_set (Date) then
    if EditorCount <= 1 then
    Editors = Editors .. ", " .. cfg.messages['editor'];
    else
    Editors = Editors .. ", " .. cfg.messages['editors'];
    end
    else
    if EditorCount <= 1 then
    Editors = Editors .. " (" .. cfg.messages['editor'] .. ")" .. sepc .. " "
    else
    Editors = Editors .. " (" .. cfg.messages['editors'] .. ")" .. sepc .. " "
    end
    end
    text = safe_join( {Editors, Date, Chapter, Place, tcommon, pgtext, idcommon}, sepc );
    else
    if utilities.in_array (config.CitationClass, {"journal", "citation"}) and utilities.is_set (Periodical) then
    text = safe_join( {Chapter, Place, tcommon, pgtext, Date, idcommon}, sepc );
    else
    text = safe_join( {Chapter, Place, tcommon, Date, pgtext, idcommon}, sepc );
    end
    end
    if utilities.is_set (PostScript) and PostScript ~= sepc then
    text = safe_join( {text, sepc}, sepc ); -- Deals with italics, spaces, etc.
    text = text:sub(1, -sepc:len() - 1);
    end
    text = safe_join( {text, PostScript}, sepc );
     
    -- Now enclose the whole thing in a <cite> element
    local options = {};
    if utilities.is_set (config.CitationClass) and config.CitationClass ~= "citation" then
    options.class = string.format ('%s %s %s', 'citation', config.CitationClass, utilities.is_set (Mode) and Mode or 'cs1'); -- class=citation required for blue highlight when used with |ref=
    else
    options.class = string.format ('%s %s', 'citation', utilities.is_set (Mode) and Mode or 'cs2');
    end
     
    local Ref = A['Ref'];
    if 'harv' == Ref then -- need to check this before setting to default
    utilities.set_message ('maint_ref_harv'); -- add maint cat to identify templates that have this now-extraneous param value
    elseif not utilities.is_set (Ref) then
    Ref = 'harv'; -- set as default when not set externally
    end
    if 'none' ~= cfg.keywords_xlate[Ref:lower()] then
    local id = Ref
    local namelist = {}; -- holds selected contributor, author, editor name list
    local year = first_set ({Year, anchor_year}, 2); -- Year first for legacy citations and for YMD dates that require disambiguation
     
    if #c > 0 then -- if there is a contributor list
    namelist = c; -- select it
    elseif #a > 0 then -- or an author list
    namelist = a;
    elseif #e > 0 then -- or an editor list
    namelist = e;
    end
    local citeref_id
    if #namelist > 0 then -- if there are names in namelist
    citeref_id = make_citeref_id (namelist, year); -- go make the CITEREF anchor
    else
    citeref_id = ''; -- unset
    end
    if citeref_id == Ref then
    utilities.set_message ('maint_ref_duplicates_default');
    end
    if 'harv' == Ref then
    id = citeref_id
    end
    options.id = id;
    end
    if string.len(text:gsub("<span[^>/]*>(.-)</span>", "%1"):gsub("%b<>", "")) <= 2 then -- remove <span> tags and other HTML-like markup; then get length of what remains
    z.error_categories = {};
    text = utilities.set_message ('err_empty_citation');
    z.message_tail = {};
    end
    local render = {}; -- here we collect the final bits for concatenation into the rendered citation
     
    if utilities.is_set (options.id) then -- here we wrap the rendered citation in <cite ...>...</cite> tags
    table.insert (render, utilities.substitute (cfg.presentation['cite-id'], {mw.uri.anchorEncode(options.id), mw.text.nowiki(options.class), text})); -- when |ref= is set
    else
    table.insert (render, utilities.substitute (cfg.presentation['cite'], {mw.text.nowiki(options.class), text})); -- all other cases
    end
     
    table.insert (render, utilities.substitute (cfg.presentation['ocins'], {OCinSoutput})); -- append metadata to the citation
     
    if 0 ~= #z.message_tail then
    table.insert (render, ' ');
    for i,v in ipairs( z.message_tail ) do
    if utilities.is_set (v[1]) then
    if i == #z.message_tail then
    table.insert (render, utilities.error_comment ( v[1], v[2] ));
    else
    table.insert (render, utilities.error_comment ( v[1] .. "; ", v[2] ));
    end
    end
    end
    end
     
    if 0 ~= #z.maintenance_cats then
    local maint_msgs = {}; -- here we collect all of the maint messages
    for _, v in ipairs( z.maintenance_cats ) do -- append maintenance categories
    local maint = {}; -- here we assemble a maintenence message
    table.insert (maint, v); -- maint msg is the category name
    table.insert (maint, ' ('); -- open the link text
    table.insert (maint, utilities.substitute (cfg.messages[':cat wikilink'], {v})); -- add the link
    table.insert (maint, ')'); -- and close it
    table.insert (maint_msgs, table.concat (maint)); -- assemble new maint message and add it to the maint_msgs table
    end
    table.insert (render, utilities.substitute (cfg.presentation['hidden-maint'], table.concat (maint_msgs, ' '))); -- wrap the group of maint message with proper presentation and save
    end
    if not no_tracking_cats then
    for _, v in ipairs( z.error_categories ) do -- append error categories
    table.insert (render, utilities.substitute (cfg.messages['cat wikilink'], {v}));
    end
    for _, v in ipairs( z.maintenance_cats ) do -- append maintenance categories
    table.insert (render, utilities.substitute (cfg.messages['cat wikilink'], {v}));
    end
    for _, v in ipairs( z.properties_cats ) do -- append properties categories
    table.insert (render, utilities.substitute (cfg.messages['cat wikilink'], {v}));
    end
    end
     
    return table.concat (render);
    end
     
     
    --[[--------------------------< V A L I D A T E >--------------------------------------------------------------
     
    Looks for a parameter's name in one of several whitelists.
     
    Parameters in the whitelist can have three values:
    true - active, supported parameters
    false - deprecated, supported parameters
    nil - unsupported parameters
    ]]
     
    local function validate (name, cite_class, empty)
    local name = tostring (name);
    local enum_name; -- for enumerated parameters, is name with enumerator replaced with '#'
    local state;
    local function state_test (state, name) -- local function to do testing of state values
    if true == state then return true; end -- valid actively supported parameter
    if false == state then
    if empty then return nil; end -- empty deprecated parameters are treated as unknowns
    deprecated_parameter (name); -- parameter is deprecated but still supported
    return true;
    end
    if 'discouraged' == state then
    discouraged_parameter (name); -- parameter is discouraged but still supported
    return true;
    end
    return nil;
    end
     
    if name:find ('#') then -- # is a cs1|2 reserved character so parameters with # not permitted
    return nil;
    end
     
    if utilities.in_array (cite_class, whitelist.preprint_template_list ) then -- limited parameter sets allowed for these templates
    state = whitelist.limited_basic_arguments[name];
    if true == state_test (state, name) then return true; end
     
    state = whitelist.preprint_arguments[cite_class][name]; -- look in the parameter-list for the template identified by cite_class
    if true == state_test (state, name) then return true; end
     
    -- limited enumerated parameters list
    enum_name = name:gsub("%d+", "#" ); -- replace digit(s) with # (last25 becomes last#) (mw.ustring because non-Western 'local' digits)
    state = whitelist.limited_numbered_arguments[enum_name];
    if true == state_test (state, name) then return true; end
     
    return false; -- not supported because not found or name is set to nil
    end -- end limited parameter-set templates
     
    if utilities.in_array (cite_class, whitelist.unique_param_template_list) then -- experiment for template-specific parameters for templates that accept parameters from the basic argument list
    state = whitelist.unique_arguments[cite_class][name]; -- look in the template-specific parameter-lists for the template identified by cite_class
    if true == state_test (state, name) then return true; end
    end -- if here, fall into general validation
    state = whitelist.basic_arguments[name]; -- all other templates; all normal parameters allowed
    if true == state_test (state, name) then return true; end
     
    -- all enumerated parameters allowed
    enum_name = name:gsub("%d+", "#" ); -- replace digit(s) with # (last25 becomes last#) (mw.ustring because non-Western 'local' digits)
    state = whitelist.numbered_arguments[enum_name];
    if true == state_test (state, name) then return true; end
     
    return false; -- not supported because not found or name is set to nil
    end
     
     
    --[=[-------------------------< I N T E R _ W I K I _ C H E C K >----------------------------------------------
     
    check <value> for inter-language interwiki-link markup.  <prefix> must be a MediaWiki-recognized language
    code.  when these values have the form (without leading colon):
    [[<prefix>:link|label]] return label as plain-text
    [[<prefix>:link]] return <prefix>:link as plain-text
     
    return value as is else
     
    ]=]
     
    local function inter_wiki_check (parameter, value)
    local prefix = value:match ('%[%[(%a+):'); -- get an interwiki prefix if one exists
    local _;
    if prefix and cfg.inter_wiki_map[prefix:lower()] then -- if prefix is in the map, needs preceding colon so
    table.insert( z.message_tail, {utilities.set_message ('err_bad_paramlink', parameter)}); -- emit an error message
    _, value, _ = utilities.is_wikilink (value); -- extract label portion from wikilink
    end
    return value;
    end
     
     
    --[[--------------------------< M I S S I N G _ P I P E _ C H E C K >------------------------------------------
     
    Look at the contents of a parameter. If the content has a string of characters and digits followed by an equal
    sign, compare the alphanumeric string to the list of cs1|2 parameters.  If found, then the string is possibly a
    parameter that is missing its pipe.  There are two tests made:
    {{cite ... |title=Title access-date=2016-03-17}} -- the first parameter has a value and whitespace separates that value from the missing pipe parameter name
    {{cite ... |title=access-date=2016-03-17}} -- the first parameter has no value (whitespace after the first = is trimmed by MediaWiki)
    cs1|2 shares some parameter names with XML/HTML attributes: class=, title=, etc.  To prevent false positives XML/HTML
    tags are removed before the search.
     
    If a missing pipe is detected, this function adds the missing pipe maintenance category.
     
    ]]
     
    local function missing_pipe_check (parameter, value)
    local capture;
    value = value:gsub ('%b<>', ''); -- remove XML/HTML tags because attributes: class=, title=, etc.
     
    capture = value:match ('%s+(%a[%w%-]+)%s*=') or value:match ('^(%a[%w%-]+)%s*='); -- find and categorize parameters with possible missing pipes
    if capture and validate (capture) then -- if the capture is a valid parameter name
    table.insert( z.message_tail, {utilities.set_message ('err_missing_pipe', parameter)});
    end
    end
     
     
    --[[--------------------------< H A S _ E X T R A N E O U S _ P U N C T >--------------------------------------
     
    look for extraneous terminal punctuation in most parameter values; parameters listed in skip table are not checked
     
    ]]
     
    local function has_extraneous_punc (param, value)
    if 'number' == type (param) then
    return;
    end
    param = param:gsub ('%d+', '#'); -- enumerated name-list mask params allow terminal punct; normalize
    if cfg.punct_skip[param] then
    return; -- parameter name found in the skip table so done
    end
    if value:match ('[,;:]$') then
    utilities.set_message ('maint_extra_punct'); -- has extraneous punctuation; add maint cat
    end
    end
     
     
    --[[--------------------------< C I T A T I O N >--------------------------------------------------------------
     
    This is used by templates such as {{cite book}} to create the actual citation text.
     
    ]]
     
    local function citation(frame)
    Frame = frame; -- save a copy in case we need to display an error message in preview mode
    local pframe = frame:getParent()
    local styles;
    if nil ~= string.find (frame:getTitle(), 'sandbox', 1, true) then -- did the {{#invoke:}} use sandbox version?
    cfg = mw.loadData ('Module:Citation/CS1/Configuration/sandbox'); -- load sandbox versions of support modules
    whitelist = mw.loadData ('Module:Citation/CS1/Whitelist/sandbox');
    utilities = require ('Module:Citation/CS1/Utilities/sandbox');
    validation = require ('Module:Citation/CS1/Date_validation/sandbox');
    identifiers = require ('Module:Citation/CS1/Identifiers/sandbox');
    metadata = require ('Module:Citation/CS1/COinS/sandbox');
    styles = 'Module:Citation/CS1/sandbox/styles.css';
    else -- otherwise
    cfg = mw.loadData ('Module:Citation/CS1/Configuration'); -- load live versions of support modules
    whitelist = mw.loadData ('Module:Citation/CS1/Whitelist');
    utilities = require ('Module:Citation/CS1/Utilities');
    validation = require ('Module:Citation/CS1/Date_validation');
    identifiers = require ('Module:Citation/CS1/Identifiers');
    metadata = require ('Module:Citation/CS1/COinS');
    styles = 'Module:Citation/CS1/styles.css';
    end
     
    utilities.set_selected_modules (cfg); -- so that functions in Utilities can see the selected cfg tables
    identifiers.set_selected_modules (cfg, utilities); -- so that functions in Identifiers can see the selected cfg tables and selected Utilities module
    validation.set_selected_modules (cfg, utilities); -- so that functions in Date validataion can see selected cfg tables and the selected Utilities module
    metadata.set_selected_modules (cfg, utilities); -- so that functions in COinS can see the selected cfg tables and selected Utilities module
     
    z = utilities.z; -- table of error and category tables in Module:Citation/CS1/Utilities
     
    local args = {}; -- table where we store all of the template's arguments
    local suggestions = {}; -- table where we store suggestions if we need to loadData them
    local error_text, error_state;
     
    local config = {}; -- table to store parameters from the module {{#invoke:}}
    for k, v in pairs( frame.args ) do -- get parameters from the {{#invoke}} frame
    config[k] = v;
    -- args[k] = v; -- crude debug support that allows us to render a citation from module {{#invoke:}}; skips parameter validation; TODO: keep?
    end
     
    local capture; -- the single supported capture when matching unknown parameters using patterns
    local empty_unknowns = {}; -- sequence table to hold empty unknown params for error message listing
    for k, v in pairs( pframe.args ) do -- get parameters from the parent (template) frame
    v = mw.ustring.gsub (v, '^%s*(.-)%s*$', '%1'); -- trim leading/trailing whitespace; when v is only whitespace, becomes empty string
    if v ~= '' then
    if ('string' == type (k)) then
    k = mw.ustring.gsub (k, '%d', cfg.date_names.local_digits); -- for enumerated parameters, translate 'local' digits to Western 0-9
    end
    if not validate( k, config.CitationClass ) then
    error_text = "";
    if type( k ) ~= 'string' then
    -- exclude empty numbered parameters
    if v:match("%S+") ~= nil then
    error_text, error_state = utilities.set_message ( 'err_text_ignored', {v}, true );
    end
    elseif validate( k:lower(), config.CitationClass ) then
    error_text, error_state = utilities.set_message ( 'err_parameter_ignored_suggest', {k, k:lower()}, true ); -- suggest the lowercase version of the parameter
    else
    if nil == suggestions.suggestions then -- if this table is nil then we need to load it
    if nil ~= string.find (frame:getTitle(), 'sandbox', 1, true) then -- did the {{#invoke:}} use sandbox version?
    suggestions = mw.loadData( 'Module:Citation/CS1/Suggestions/sandbox' ); -- use the sandbox version
    else
    suggestions = mw.loadData( 'Module:Citation/CS1/Suggestions' ); -- use the live version
    end
    end
    for pattern, param in pairs (suggestions.patterns) do -- loop through the patterns to see if we can suggest a proper parameter
    capture = k:match (pattern); -- the whole match if no capture in pattern else the capture if a match
    if capture then -- if the pattern matches
    param = utilities.substitute (param, capture); -- add the capture to the suggested parameter (typically the enumerator)
    if validate (param, config.CitationClass) then -- validate the suggestion to make sure that the suggestion is supported by this template (necessary for limited parameter lists)
    error_text, error_state = utilities.set_message ('err_parameter_ignored_suggest', {k, param}, true); -- set the suggestion error message
    else
    error_text, error_state = utilities.set_message ( 'err_parameter_ignored', {k}, true ); -- suggested param not supported by this template
    v = ''; -- unset
    end
    end
    end
    if not utilities.is_set (error_text) then -- couldn't match with a pattern, is there an explicit suggestion?
    if (suggestions.suggestions[ k:lower() ] ~= nil) and validate (suggestions.suggestions[ k:lower() ], config.CitationClass) then
    error_text, error_state = utilities.set_message ( 'err_parameter_ignored_suggest', {k, suggestions.suggestions[ k:lower() ]}, true );
    else
    error_text, error_state = utilities.set_message ( 'err_parameter_ignored', {k}, true );
    v = ''; -- unset value assigned to unrecognized parameters (this for the limited parameter lists)
    end
    end
    end
    elseif validate( k:lower() ) then
    error_text, error_state = set_error( 'parameter_ignored_suggest', {k, k:lower()}, true );
    else
    if nil == suggestions.suggestions then -- if this table is nil then we need to load it
    if nil ~= string.find (frame:getTitle(), 'sandbox', 1, true) then -- did the {{#invoke:}} use sandbox version?
    suggestions = mw.loadData( 'Module:Citation/CS1/Suggestions/sandbox' ); -- use the sandbox version
    else
    suggestions = mw.loadData( 'Module:Citation/CS1/Suggestions' ); -- use the live version
    end
    end
    for pattern, param in pairs (suggestions.patterns) do -- loop through the patterns to see if we can suggest a proper parameter
    capture = k:match (pattern); -- the whole match if no caputre in pattern else the capture if a match
    if capture then -- if the pattern matches
    param = substitute( param, capture ); -- add the capture to the suggested parameter (typically the enumerator)
    error_text, error_state = set_error( 'parameter_ignored_suggest', {k, param}, true ); -- set the error message
    end
    end
    if not is_set (error_text) then -- couldn't match with a pattern, is there an expicit suggestion?
    if suggestions.suggestions[ k:lower() ] ~= nil then
    error_text, error_state = set_error( 'parameter_ignored_suggest', {k, suggestions.suggestions[ k:lower() ]}, true );
    else
    error_text, error_state = set_error( 'parameter_ignored', {k}, true );
    end
    end
    -- if #suggestions == 0 then
    -- suggestions = mw.loadData( 'Module:Citation/CS1/Suggestions' );
    -- end
    -- if suggestions[ k:lower() ] ~= nil then
    -- error_text, error_state = set_error( 'parameter_ignored_suggest', {k, suggestions[ k:lower() ]}, true );
    -- else
    -- error_text, error_state = set_error( 'parameter_ignored', {k}, true );
    -- end
    end    
    end    
    if error_text ~= '' then
    if error_text ~= '' then
    Line 3,628: Line 4,134:
    end
    end
    end
    end
    args[k] = v;
     
    elseif args[k] ~= nil or (k == 'postscript') then
    args[k] = v; -- save this parameter and its value
    args[k] = v;
     
    end
    elseif not utilities.is_set (v) then -- for empty parameters
    if not validate (k, config.CitationClass, true) then -- is this empty parameter a valid parameter
    k = ('' == k) and '(empty string)' or k; -- when k is empty string (or was space(s) trimmed to empty string), replace with descriptive text
    table.insert (empty_unknowns, utilities.wrap_style ('parameter', k)); -- format for error message and add to the list
    end
    -- crude debug support that allows us to render a citation from module {{#invoke:}} TODO: keep?
    -- elseif args[k] ~= nil or (k == 'postscript') then -- when args[k] has a value from {{#invoke}} frame (we don't normally do that)
    -- args[k] = v; -- overwrite args[k] with empty string from pframe.args[k] (template frame); v is empty string here
    end -- not sure about the postscript bit; that gets handled in parameter validation; historical artifact?
    end
    end
     
    return citation0( config, args)
    if 0 ~= #empty_unknowns then -- create empty unknown error message
    table.insert (z.message_tail, {utilities.set_message ('err_param_unknown_empty', {
    1 == #empty_unknowns and '' or 's',
    utilities.make_sep_list (#empty_unknowns, empty_unknowns)
    }, true )});
    end
     
    for k, v in pairs( args ) do
    if 'string' == type (k) then -- don't evaluate positional parameters
    has_invisible_chars (k, v); -- look for invisible characters
    end
    has_extraneous_punc (k, v); -- look for extraneous terminal punctuation in parameter values
    missing_pipe_check (k, v); -- do we think that there is a parameter that is missing a pipe?
    args[k] = inter_wiki_check (k, v); -- when language interwiki-linked parameter missing leading colon replace with wiki-link label
    end
     
    return table.concat ({
    frame:extensionTag ('templatestyles', '', {src=styles}),
    citation0( config, args)
    });
    end
    end


    return z
    --[[--------------------------< E X P O R T E D  F U N C T I O N S >------------------------------------------
    ]]
     
    return {citation = citation};

    Latest revision as of 11:41, 21 May 2021

    Documentation for this module may be created at Module:Citation/CS1/doc 

    
require('Module:No globals');

--[[--------------------------< F O R W A R D   D E C L A R A T I O N S >--------------------------------------
each of these counts against the Lua upvalue limit
]]

local validation;																-- functions in Module:Citation/CS1/Date_validation

local utilities;																-- functions in Module:Citation/CS1/Utilities
local z ={};																	-- table of tables in Module:Citation/CS1/Utilities

local identifiers;																-- functions and tables in Module:Citation/CS1/Identifiers
local metadata;																	-- functions in Module:Citation/CS1/COinS
local cfg = {};																	-- table of configuration tables that are defined in Module:Citation/CS1/Configuration
local whitelist = {};															-- table of tables listing valid template parameter names; defined in Module:Citation/CS1/Whitelist

--[[------------------< P A G E   S C O P E   V A R I A B L E S >---------------
declare variables here that have page-wide scope that are not brought in from
other modules; that are created here and used here
]]
local added_deprecated_cat;														-- Boolean flag so that the category is added only once
local added_discouraged_cat;													-- Boolean flag so that the category is added only once
local added_vanc_errs;															-- Boolean flag so we only emit one Vancouver error / category
local Frame;																	-- holds the module's frame table

--[[--------------------------< F I R S T _ S E T >------------------------------------------------------------

Locates and returns the first set value in a table of values where the order established in the table,
left-to-right (or top-to-bottom), is the order in which the values are evaluated.  Returns nil if none are set.

This version replaces the original 'for _, val in pairs do' and a similar version that used ipairs.  With the pairs
version the order of evaluation could not be guaranteed.  With the ipairs version, a nil value would terminate
the for-loop before it reached the actual end of the list.

]]

local function first_set (list, count)
	local i = 1;
	while i <= count do															-- loop through all items in list
		if utilities.is_set( list[i] ) then
			return list[i];														-- return the first set list member
		end
		i = i + 1;																-- point to next
	end
end


--[[--------------------------< A D D _ V A N C _ E R R O R >----------------------------------------------------

Adds a single Vancouver system error message to the template's output regardless of how many error actually exist.
To prevent duplication, added_vanc_errs is nil until an error message is emitted.

added_vanc_errs is a Boolean declared in page scope variables above

]]

local function add_vanc_error (source, position)
	if added_vanc_errs then return end
		
	added_vanc_errs = true;														-- note that we've added this category
	table.insert( z.message_tail, { utilities.set_message ( 'err_vancouver', {source, position}, true ) } );
end


--[[--------------------------< I S _ S C H E M E >------------------------------------------------------------

does this thing that purports to be a URI scheme seem to be a valid scheme?  The scheme is checked to see if it
is in agreement with http://tools.ietf.org/html/std66#section-3.1 which says:
	Scheme names consist of a sequence of characters beginning with a
   letter and followed by any combination of letters, digits, plus
   ("+"), period ("."), or hyphen ("-").

returns true if it does, else false

]]

local function is_scheme (scheme)
	return scheme and scheme:match ('^%a[%a%d%+%.%-]*:');						-- true if scheme is set and matches the pattern
end


--[=[-------------------------< I S _ D O M A I N _ N A M E >--------------------------------------------------

Does this thing that purports to be a domain name seem to be a valid domain name?

Syntax defined here: http://tools.ietf.org/html/rfc1034#section-3.5
BNF defined here: https://tools.ietf.org/html/rfc4234
Single character names are generally reserved; see https://tools.ietf.org/html/draft-ietf-dnsind-iana-dns-01#page-15;
	see also [[Single-letter second-level domain]]
list of TLDs: https://www.iana.org/domains/root/db

RFC 952 (modified by RFC 1123) requires the first and last character of a hostname to be a letter or a digit.  Between
the first and last characters the name may use letters, digits, and the hyphen.

Also allowed are IPv4 addresses. IPv6 not supported

domain is expected to be stripped of any path so that the last character in the last character of the TLD.  tld
is two or more alpha characters.  Any preceding '//' (from splitting a URL with a scheme) will be stripped
here.  Perhaps not necessary but retained in case it is necessary for IPv4 dot decimal.

There are several tests:
	the first character of the whole domain name including subdomains must be a letter or a digit
	internationalized domain name (ASCII characters with .xn-- ASCII Compatible Encoding (ACE) prefix xn-- in the TLD) see https://tools.ietf.org/html/rfc3490
	single-letter/digit second-level domains in the .org, .cash, and .today TLDs
	q, x, and z SL domains in the .com TLD
	i and q SL domains in the .net TLD
	single-letter SL domains in the ccTLDs (where the ccTLD is two letters)
	two-character SL domains in gTLDs (where the gTLD is two or more letters)
	three-plus-character SL domains in gTLDs (where the gTLD is two or more letters)
	IPv4 dot-decimal address format; TLD not allowed

returns true if domain appears to be a proper name and TLD or IPv4 address, else false

]=]

local function is_domain_name (domain)
	if not domain then
		return false;															-- if not set, abandon
	end
	
	domain = domain:gsub ('^//', '');											-- strip '//' from domain name if present; done here so we only have to do it once
	
	if not domain:match ('^[%w]') then											-- first character must be letter or digit
		return false;
	end

	if domain:match ('^%a+:') then												-- hack to detect things that look like s:Page:Title where Page: is namespace at Wikisource
		return false;
	end

	local patterns = {															-- patterns that look like URLs
		'%f[%w][%w][%w%-]+[%w]%.%a%a+$',										-- three or more character hostname.hostname or hostname.tld
		'%f[%w][%w][%w%-]+[%w]%.xn%-%-[%w]+$',									-- internationalized domain name with ACE prefix
		'%f[%a][qxz]%.com$',													-- assigned one character .com hostname (x.com times out 2015-12-10)
		'%f[%a][iq]%.net$',														-- assigned one character .net hostname (q.net registered but not active 2015-12-10)
		'%f[%w][%w]%.%a%a$',													-- one character hostname and ccTLD (2 chars)
		'%f[%w][%w][%w]%.%a%a+$',												-- two character hostname and TLD
		'^%d%d?%d?%.%d%d?%d?%.%d%d?%d?%.%d%d?%d?',								-- IPv4 address
		}

	for _, pattern in ipairs (patterns) do										-- loop through the patterns list
		if domain:match (pattern) then
			return true;														-- if a match then we think that this thing that purports to be a URL is a URL
		end
	end

	for _, d in ipairs ({'cash', 'company', 'today', 'org'}) do					-- look for single letter second level domain names for these top level domains
		if domain:match ('%f[%w][%w]%.' .. d) then
			return true
		end
	end
	return false;																-- no matches, we don't know what this thing is
end


--[[--------------------------< I S _ U R L >------------------------------------------------------------------

returns true if the scheme and domain parts of a URL appear to be a valid URL; else false.

This function is the last step in the validation process.  This function is separate because there are cases that
are not covered by split_url(), for example is_parameter_ext_wikilink() which is looking for bracketted external
wikilinks.

]]

local function is_url (scheme, domain)
	if utilities.is_set (scheme) then											-- if scheme is set check it and domain
		return is_scheme (scheme) and is_domain_name (domain);
	else
		return is_domain_name (domain);											-- scheme not set when URL is protocol-relative
	end
end


--[[--------------------------< S P L I T _ U R L >------------------------------------------------------------

Split a URL into a scheme, authority indicator, and domain.

First remove Fully Qualified Domain Name terminator (a dot following TLD) (if any) and any path(/), query(?) or fragment(#).

If protocol-relative URL, return nil scheme and domain else return nil for both scheme and domain.

When not protocol-relative, get scheme, authority indicator, and domain.  If there is an authority indicator (one
or more '/' characters immediately following the scheme's colon), make sure that there are only 2.

Any URL that does not have news: scheme must have authority indicator (//).  TODO: are there other common schemes
like news: that don't use authority indicator?

Strip off any port and path;

]]

local function split_url (url_str)
	local scheme, authority, domain;
	
	url_str = url_str:gsub ('([%a%d])%.?[/%?#].*$', '%1');						-- strip FQDN terminator and path(/), query(?), fragment (#) (the capture prevents false replacement of '//')

	if url_str:match ('^//%S*') then											-- if there is what appears to be a protocol-relative URL
		domain = url_str:match ('^//(%S*)')
	elseif url_str:match ('%S-:/*%S+') then										-- if there is what appears to be a scheme, optional authority indicator, and domain name
		scheme, authority, domain = url_str:match ('(%S-:)(/*)(%S+)');			-- extract the scheme, authority indicator, and domain portions
		if utilities.is_set (authority) then
			authority = authority:gsub ('//', '', 1);							-- replace place 1 pair of '/' with nothing;
			if utilities.is_set(authority) then									-- if anything left (1 or 3+ '/' where authority should be) then
				return scheme;													-- return scheme only making domain nil which will cause an error message
			end
		else
			if not scheme:match ('^news:') then									-- except for news:..., MediaWiki won't link URLs that do not have authority indicator; TODO: a better way to do this test?
				return scheme;													-- return scheme only making domain nil which will cause an error message
			end
		end
		domain = domain:gsub ('(%a):%d+', '%1');								-- strip port number if present
	end
	
	return scheme, domain;
end


--[[--------------------------< L I N K _ P A R A M _ O K >---------------------------------------------------

checks the content of |title-link=, |series-link=, |author-link=, etc. for properly formatted content: no wikilinks, no URLs

Link parameters are to hold the title of a Wikipedia article, so none of the WP:TITLESPECIALCHARACTERS are allowed:
	# < > [ ] | { } _
except the underscore which is used as a space in wiki URLs and # which is used for section links

returns false when the value contains any of these characters.

When there are no illegal characters, this function returns TRUE if value DOES NOT appear to be a valid URL (the
|<param>-link= parameter is ok); else false when value appears to be a valid URL (the |<param>-link= parameter is NOT ok).

]]

local function link_param_ok (value)
	local scheme, domain;
	if value:find ('[<>%[%]|{}]') then											-- if any prohibited characters
		return false;
	end

	scheme, domain = split_url (value);											-- get scheme or nil and domain or nil from URL; 
	return not is_url (scheme, domain);											-- return true if value DOES NOT appear to be a valid URL
end


--[[--------------------------< L I N K _ T I T L E _ O K >---------------------------------------------------

Use link_param_ok() to validate |<param>-link= value and its matching |<title>= value.

|<title>= may be wiki-linked but not when |<param>-link= has a value.  This function emits an error message when
that condition exists

check <link> for inter-language interwiki-link prefix.  prefix must be a MediaWiki-recognized language
code and must begin with a colon.

]]

local function link_title_ok (link, lorig, title, torig)
local orig;
	if utilities.is_set (link) then 											-- don't bother if <param>-link doesn't have a value
		if not link_param_ok (link) then										-- check |<param>-link= markup
			orig = lorig;														-- identify the failing link parameter
		elseif title:find ('%[%[') then											-- check |title= for wikilink markup
			orig = torig;														-- identify the failing |title= parameter
		elseif link:match ('^%a+:') then										-- if the link is what looks like an interwiki
			local prefix = link:match ('^(%a+):'):lower();						-- get the interwiki prefix

			if cfg.inter_wiki_map[prefix] then									-- if prefix is in the map, must have preceding colon
				orig = lorig;													-- flag as error
			end
		end
	end

	if utilities.is_set (orig) then
		link = '';																-- unset
		table.insert( z.message_tail, { utilities.set_message ( 'err_bad_paramlink', orig)});	-- URL or wikilink in |title= with |title-link=;
	end
	
	return link;																-- link if ok, empty string else
end


--[[--------------------------< C H E C K _ U R L >------------------------------------------------------------

Determines whether a URL string appears to be valid.

First we test for space characters.  If any are found, return false.  Then split the URL into scheme and domain
portions, or for protocol-relative (//example.com) URLs, just the domain.  Use is_url() to validate the two
portions of the URL.  If both are valid, or for protocol-relative if domain is valid, return true, else false.

Because it is different from a standard URL, and because this module used external_link() to make external links
that work for standard and news: links, we validate newsgroup names here.  The specification for a newsgroup name
is at https://tools.ietf.org/html/rfc5536#section-3.1.4

]]

local function check_url( url_str )
	if nil == url_str:match ("^%S+$") then										-- if there are any spaces in |url=value it can't be a proper URL
		return false;
	end
	local scheme, domain;

	scheme, domain = split_url (url_str);										-- get scheme or nil and domain or nil from URL;
	
	if 'news:' == scheme then													-- special case for newsgroups
		return domain:match('^[%a%d%+%-_]+%.[%a%d%+%-_%.]*[%a%d%+%-_]$');
	end
	
	return is_url (scheme, domain);												-- return true if value appears to be a valid URL
end


--[=[-------------------------< I S _ P A R A M E T E R _ E X T _ W I K I L I N K >----------------------------

Return true if a parameter value has a string that begins and ends with square brackets [ and ] and the first
non-space characters following the opening bracket appear to be a URL.  The test will also find external wikilinks
that use protocol-relative URLs. Also finds bare URLs.

The frontier pattern prevents a match on interwiki-links which are similar to scheme:path URLs.  The tests that
find bracketed URLs are required because the parameters that call this test (currently |title=, |chapter=, |work=,
and |publisher=) may have wikilinks and there are articles or redirects like '//Hus' so, while uncommon, |title=[[//Hus]]
is possible as might be [[en://Hus]].

]=]

local function is_parameter_ext_wikilink (value)
local scheme, domain;

	if value:match ('%f[%[]%[%a%S*:%S+.*%]') then								-- if ext. wikilink with scheme and domain: [xxxx://yyyyy.zzz]
		scheme, domain = split_url (value:match ('%f[%[]%[(%a%S*:%S+).*%]'));
	elseif value:match ('%f[%[]%[//%S+.*%]') then								-- if protocol-relative ext. wikilink: [//yyyyy.zzz]
		scheme, domain = split_url (value:match ('%f[%[]%[(//%S+).*%]'));
	elseif value:match ('%a%S*:%S+') then										-- if bare URL with scheme; may have leading or trailing plain text
		scheme, domain = split_url (value:match ('(%a%S*:%S+)'));
	elseif value:match ('//%S+') then											-- if protocol-relative bare URL: //yyyyy.zzz; may have leading or trailing plain text
		scheme, domain = split_url (value:match ('(//%S+)'));					-- what is left should be the domain
	else
		return false;															-- didn't find anything that is obviously a URL
	end

	return is_url (scheme, domain);												-- return true if value appears to be a valid URL
end


--[[-------------------------< C H E C K _ F O R _ U R L >-----------------------------------------------------

loop through a list of parameters and their values.  Look at the value and if it has an external link, emit an error message.

]]

local function check_for_url (parameter_list)
local error_message = '';
	for k, v in pairs (parameter_list) do										-- for each parameter in the list
		if is_parameter_ext_wikilink (v) then									-- look at the value; if there is a URL add an error message
			if utilities.is_set(error_message) then								-- once we've added the first portion of the error message ...
				error_message = error_message .. ", ";							-- ... add a comma space separator
			end
			error_message = error_message .. "&#124;" .. k .. "=";				-- add the failed parameter
		end
	end
	if utilities.is_set (error_message) then									-- done looping, if there is an error message, display it
		table.insert( z.message_tail, { utilities.set_message ( 'err_param_has_ext_link', {error_message}, true ) } );
	end
end


--[[--------------------------< S A F E _ F O R _ U R L >------------------------------------------------------

Escape sequences for content that will be used for URL descriptions

]]

local function safe_for_url( str )
	if str:match( "%[%[.-%]%]" ) ~= nil then 
		table.insert( z.message_tail, { utilities.set_message ( 'err_wikilink_in_url', {}, true ) } );
	end
	
	return str:gsub( '[%[%]\n]', {	
		['['] = '&#91;',
		[']'] = '&#93;',
		['\n'] = ' ' } );
end


--[[--------------------------< E X T E R N A L _ L I N K >----------------------------------------------------

Format an external link with error checking

]]

local function external_link( URL, label, source, access)
	local error_str = "";
	local domain;
	local path;
	local base_url;

	if not utilities.is_set ( label ) then
		label = URL;
		if utilities.is_set ( source ) then
			error_str = utilities.set_message ( 'err_bare_url_missing_title', { utilities.wrap_style ('parameter', source) }, false, " " );
		else
			error( cfg.messages["bare_url_no_origin"] );
		end			
	end
	if not check_url( URL ) then
		error_str = utilities.set_message ( 'err_bad_url', {utilities.wrap_style ('parameter', source)}, false, " " ) .. error_str;
	end
	
	domain, path = URL:match ('^([/%.%-%+:%a%d]+)([/%?#].*)$');					-- split the URL into scheme plus domain and path
	if path then																-- if there is a path portion
		path = path:gsub ('[%[%]]', {['['] = '%5b', [']'] = '%5d'});			-- replace '[' and ']' with their percent-encoded values
		URL = table.concat ({domain, path});									-- and reassemble
	end

	base_url = table.concat({ "[", URL, " ", safe_for_url (label), "]" });		-- assemble a wiki-markup URL

	if utilities.is_set (access) then											-- access level (subscription, registration, limited)
		base_url = utilities.substitute (cfg.presentation['ext-link-access-signal'], {cfg.presentation[access].class, cfg.presentation[access].title, base_url});	-- add the appropriate icon
	end
	
	return table.concat ({base_url, error_str});
end


--[[--------------------------< D E P R E C A T E D _ P A R A M E T E R >--------------------------------------

Categorize and emit an error message when the citation contains one or more deprecated parameters.  The function includes the
offending parameter name to the error message.  Only one error message is emitted regardless of the number of deprecated
parameters in the citation.

added_deprecated_cat is a Boolean declared in page scope variables above

]]

local function deprecated_parameter(name)
	if not added_deprecated_cat then
		added_deprecated_cat = true;											-- note that we've added this category
		table.insert( z.message_tail, { utilities.set_message ( 'err_deprecated_params', {name}, true ) } );	-- add error message
	end
end


--[[--------------------------< D I S C O U R A G E D _ P A R A M E T E R >------------------------------------

Categorize and emit an maintenance message when the citation contains one or more discouraged parameters.  Only
one error message is emitted regardless of the number of discouraged parameters in the citation.

added_discouraged_cat is a Boolean declared in page scope variables above

]]

local function discouraged_parameter(name)
	if not added_discouraged_cat then
		added_discouraged_cat = true;											-- note that we've added this category
		table.insert( z.message_tail, { utilities.set_message ( 'maint_discouraged', {name}, true ) } );	-- add maint message
	end
end


--[=[-------------------------< K E R N _ Q U O T E S >--------------------------------------------------------

Apply kerning to open the space between the quote mark provided by the module and a leading or trailing quote
mark contained in a |title= or |chapter= parameter's value.

This function will positive kern either single or double quotes:
	"'Unkerned title with leading and trailing single quote marks'"
	" 'Kerned title with leading and trailing single quote marks' " (in real life the kerning isn't as wide as this example)
Double single quotes (italic or bold wiki-markup) are not kerned.

Replaces Unicode quote marks in plain text or in the label portion of a [[L|D]] style wikilink with typewriter
quote marks regardless of the need for kerning.  Unicode quote marks are not replaced in simple [[D]] wikilinks.

Call this function for chapter titles, for website titles, etc.; not for book titles.

]=]

local function kern_quotes (str)
	local cap = '';
	local cap2 = '';
	local wl_type, label, link;

	wl_type, label, link = utilities.is_wikilink (str);							-- wl_type is: 0, no wl (text in label variable); 1, [[D]]; 2, [[L|D]]
	
	if 1 == wl_type then														-- [[D]] simple wikilink with or without quote marks
		if mw.ustring.match (str, '%[%[[\"“”\'‘’].+[\"“”\'‘’]%]%]') then		-- leading and trailing quote marks
			str = utilities.substitute (cfg.presentation['kern-wl-both'], str);
		elseif mw.ustring.match (str, '%[%[[\"“”\'‘’].+%]%]')	then			-- leading quote marks
			str = utilities.substitute (cfg.presentation['kern-wl-left'], str);
		elseif mw.ustring.match (str, '%[%[.+[\"“”\'‘’]%]%]') then				-- trailing quote marks
			str = utilities.substitute (cfg.presentation['kern-wl-right'], str);
		end

	else																		-- plain text or [[L|D]]; text in label variable
		label = mw.ustring.gsub (label, '[“”]', '\"');							-- replace “” (U+201C & U+201D) with " (typewriter double quote mark)
		label = mw.ustring.gsub (label, '[‘’]', '\'');							-- replace ‘’ (U+2018 & U+2019) with ' (typewriter single quote mark)

		cap, cap2 = mw.ustring.match (label, "^([\"\'])([^\'].+)");				-- match leading double or single quote but not doubled single quotes (italic markup)
		if utilities.is_set (cap) then
			label = utilities.substitute (cfg.presentation['kern-left'], {cap, cap2});
		end
	
		cap, cap2 = mw.ustring.match (label, "^(.+[^\'])([\"\'])$")				-- match trailing double or single quote but not doubled single quotes (italic markup)
		if utilities.is_set (cap) then
			label = utilities.substitute (cfg.presentation['kern-right'], {cap, cap2});
		end
		
		if 2 == wl_type then
			str = utilities.make_wikilink (link, label);						-- reassemble the wikilink
		else
			str = label;
		end
	end
	return str;
end


--[[--------------------------< F O R M A T _ S C R I P T _ V A L U E >----------------------------------------

|script-title= holds title parameters that are not written in Latin-based scripts: Chinese, Japanese, Arabic, Hebrew, etc. These scripts should
not be italicized and may be written right-to-left.  The value supplied by |script-title= is concatenated onto Title after Title has been wrapped
in italic markup.

Regardless of language, all values provided by |script-title= are wrapped in <bdi>...</bdi> tags to isolate RTL languages from the English left to right.

|script-title= provides a unique feature.  The value in |script-title= may be prefixed with a two-character ISO 639-1 language code and a colon:
	|script-title=ja:*** *** (where * represents a Japanese character)
Spaces between the two-character code and the colon and the colon and the first script character are allowed:
	|script-title=ja : *** ***
	|script-title=ja: *** ***
	|script-title=ja :*** ***
Spaces preceding the prefix are allowed: |script-title = ja:*** ***

The prefix is checked for validity.  If it is a valid ISO 639-1 language code, the lang attribute (lang="ja") is added to the <bdi> tag so that browsers can
know the language the tag contains.  This may help the browser render the script more correctly.  If the prefix is invalid, the lang attribute
is not added.  At this time there is no error message for this condition.

Supports |script-title=, |script-chapter=, |script-<periodical>=

]]

local function format_script_value (script_value, script_param)
	local lang='';																-- initialize to empty string
	local name;
	if script_value:match('^%l%l%l?%s*:') then									-- if first 3 or 4 non-space characters are script language prefix
		lang = script_value:match('^(%l%l%l?)%s*:%s*%S.*');						-- get the language prefix or nil if there is no script
		if not utilities.is_set (lang) then
			table.insert( z.message_tail, { utilities.set_message ( 'err_script_parameter', {script_param, 'missing title part'}, true ) } );		-- prefix without 'title'; add error message
			return '';															-- script_value was just the prefix so return empty string
		end
																				-- if we get this far we have prefix and script
		name = cfg.lang_code_remap[lang] or mw.language.fetchLanguageName( lang, cfg.this_wiki_code );	-- get language name so that we can use it to categorize
		if utilities.is_set (name) then											-- is prefix a proper ISO 639-1 language code?
			script_value = script_value:gsub ('^%l+%s*:%s*', '');				-- strip prefix from script
																				-- is prefix one of these language codes?
			if utilities.in_array (lang, cfg.script_lang_codes) then
				utilities.add_prop_cat ('script_with_name', {name, lang})
			else
				table.insert( z.message_tail, { utilities.set_message ( 'err_script_parameter', {script_param, 'unknown language code'}, true ) } );	-- unknown script-language; add error message
			end
			lang = ' lang="' .. lang .. '" ';									-- convert prefix into a lang attribute
		else
			table.insert( z.message_tail, { utilities.set_message ( 'err_script_parameter', {script_param, 'invalid language code'}, true ) } );		-- invalid language code; add error message
			lang = '';															-- invalid so set lang to empty string
		end
	else
		table.insert( z.message_tail, { utilities.set_message ( 'err_script_parameter', {script_param, 'missing prefix'}, true ) } );				-- no language code prefix; add error message
	end
	script_value = utilities.substitute (cfg.presentation['bdi'], {lang, script_value});	-- isolate in case script is RTL

	return script_value;
end


--[[--------------------------< S C R I P T _ C O N C A T E N A T E >------------------------------------------

Initially for |title= and |script-title=, this function concatenates those two parameter values after the script value has been 
wrapped in <bdi> tags.
]]

local function script_concatenate (title, script, script_param)
	if utilities.is_set (script) then
		script = format_script_value (script, script_param);					-- <bdi> tags, lang attribute, categorization, etc.; returns empty string on error
		if utilities.is_set (script) then
			title = title .. ' ' .. script;										-- concatenate title and script title
		end
	end
	return title;
end


--[[--------------------------< W R A P _ M S G >--------------------------------------------------------------

Applies additional message text to various parameter values. Supplied string is wrapped using a message_list
configuration taking one argument.  Supports lower case text for {{citation}} templates.  Additional text taken
from citation_config.messages - the reason this function is similar to but separate from wrap_style().

]]

local function wrap_msg (key, str, lower)
	if not utilities.is_set ( str ) then
		return "";
	end
	if true == lower then
		local msg;
		msg = cfg.messages[key]:lower();										-- set the message to lower case before 
		return utilities.substitute ( msg, str );								-- including template text
	else
		return utilities.substitute ( cfg.messages[key], str );
	end		
end


--[[----------------< W I K I S O U R C E _ U R L _ M A K E >-------------------

Makes a Wikisource URL from Wikisource interwiki-link.  Returns the URL and appropriate
label; nil else.

str is the value assigned to |chapter= (or aliases) or |title= or |title-link=

]]

local function wikisource_url_make (str)
	local wl_type, D, L;
	local ws_url, ws_label;
	local wikisource_prefix = table.concat ({'https://', cfg.this_wiki_code, '.wikisource.org/wiki/'});

	wl_type, D, L = utilities.is_wikilink (str);								-- wl_type is 0 (not a wikilink), 1 (simple wikilink), 2 (complex wikilink)

	if 0 == wl_type then														-- not a wikilink; might be from |title-link=
		str = D:match ('^[Ww]ikisource:(.+)') or D:match ('^[Ss]:(.+)');		-- article title from interwiki link with long-form or short-form namespace
		if utilities.is_set (str) then
			ws_url = table.concat ({											-- build a Wikisource URL
				wikisource_prefix,												-- prefix
				str,															-- article title
				});
			ws_label = str;														-- label for the URL
		end
	elseif 1 == wl_type then													-- simple wikilink: [[Wikisource:ws article]]
		str = D:match ('^[Ww]ikisource:(.+)') or D:match ('^[Ss]:(.+)');		-- article title from interwiki link with long-form or short-form namespace
		if utilities.is_set (str) then
			ws_url = table.concat ({											-- build a Wikisource URL
				wikisource_prefix,												-- prefix
				str,															-- article title
				});
			ws_label = str;														-- label for the URL
		end
	elseif 2 == wl_type then													-- non-so-simple wikilink: [[Wikisource:ws article|displayed text]] ([[L|D]])
		str = L:match ('^[Ww]ikisource:(.+)') or L:match ('^[Ss]:(.+)');		-- article title from interwiki link with long-form or short-form namespace
		if utilities.is_set (str) then
			ws_label = D;														-- get ws article name from display portion of interwiki link
			ws_url = table.concat ({											-- build a Wikisource URL
				wikisource_prefix,												-- prefix
				str,															-- article title without namespace from link portion of wikilink
				});
		end
	end

	if ws_url then
		ws_url = mw.uri.encode (ws_url, 'WIKI');								-- make a usable URL
		ws_url = ws_url:gsub ('%%23', '#');										-- undo percent-encoding of fragment marker
	end

	return ws_url, ws_label, L or D;											-- return proper URL or nil and a label or nil
end


--[[----------------< F O R M A T _ P E R I O D I C A L >-----------------------

Format the three periodical parameters: |script-<periodical>=, |<periodical>=,
and |trans-<periodical>= into a single Periodical meta-parameter.

]]

local function format_periodical (script_periodical, script_periodical_source, periodical, trans_periodical)
	local periodical_error = '';

	if not utilities.is_set (periodical) then
		periodical = '';														-- to be safe for concatenation
	else
		periodical = utilities.wrap_style ('italic-title', periodical);			-- style 
	end

	periodical = script_concatenate (periodical, script_periodical, script_periodical_source);	-- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped

	if utilities.is_set (trans_periodical) then
		trans_periodical = utilities.wrap_style ('trans-italic-title', trans_periodical);
		if utilities.is_set (periodical) then
			periodical = periodical .. ' ' .. trans_periodical;
		else																	-- here when trans-periodical without periodical or script-periodical
			periodical = trans_periodical;
			periodical_error = ' ' .. utilities.set_message ('err_trans_missing_title', {'periodical'});
		end
	end

	return periodical .. periodical_error;
end


--[[------------------< F O R M A T _ C H A P T E R _ T I T L E >---------------

Format the four chapter parameters: |script-chapter=, |chapter=, |trans-chapter=,
and |chapter-url= into a single chapter meta- parameter (chapter_url_source used
for error messages).

]]

local function format_chapter_title (script_chapter, script_chapter_source, chapter, chapter_source, trans_chapter, trans_chapter_source, chapter_url, chapter_url_source, no_quotes, access)
	local chapter_error = '';

	local ws_url, ws_label, L = wikisource_url_make (chapter);					-- make a wikisource URL and label from a wikisource interwiki link
	if ws_url then
		ws_label = ws_label:gsub ('_', ' ');									-- replace underscore separators with space characters
		chapter = ws_label;
	end

	if not utilities.is_set (chapter) then
		chapter = '';															-- to be safe for concatenation
	else
		if false == no_quotes then
			chapter = kern_quotes (chapter);									-- if necessary, separate chapter title's leading and trailing quote marks from module provided quote marks
			chapter = utilities.wrap_style ('quoted-title', chapter);
		end
	end

	chapter = script_concatenate (chapter, script_chapter, script_chapter_source);	-- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped

	if utilities.is_set (chapter_url) then
		chapter = external_link (chapter_url, chapter, chapter_url_source, access);	-- adds bare_url_missing_title error if appropriate
	elseif ws_url then
		chapter = external_link (ws_url, chapter .. '&nbsp;', 'ws link in chapter');	-- adds bare_url_missing_title error if appropriate; space char to move icon away from chap text; TODO: better way to do this?
		chapter = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, chapter});				
	end

	if utilities.is_set (trans_chapter) then
		trans_chapter = utilities.wrap_style ('trans-quoted-title', trans_chapter);
		if utilities.is_set (chapter) then
			chapter = chapter .. ' ' .. trans_chapter;
		else																	-- here when trans_chapter without chapter or script-chapter
			chapter = trans_chapter;
			chapter_source = trans_chapter_source:match ('trans%-?(.+)');		-- when no chapter, get matching name from trans-<param>
			chapter_error = ' ' .. utilities.set_message ('err_trans_missing_title', {chapter_source});
		end
	end

	return chapter .. chapter_error;
end


--[[----------------< H A S _ I N V I S I B L E _ C H A R S >-------------------

This function searches a parameter's value for non-printable or invisible characters.
The search stops at the first match.

This function will detect the visible replacement character when it is part of the Wikisource.

Detects but ignores nowiki and math stripmarkers.  Also detects other named stripmarkers
(gallery, math, pre, ref) and identifies them with a slightly different error message.
See also coins_cleanup().

Output of this function is an error message that identifies the character or the
Unicode group, or the stripmarker that was detected along with its position (or,
for multi-byte characters, the position of its first byte) in the parameter value.

]]

local function has_invisible_chars (param, v)
	local position = '';														-- position of invisible char or starting position of stripmarker
	local capture;																-- used by stripmarker detection to hold name of the stripmarker
	local stripmarker;															-- boolean set true when a stripmarker is found

	capture = string.match (v, '[%w%p ]*');										-- test for values that are simple ASCII text and bypass other tests if true
	if capture == v then														-- if same there are no Unicode characters
		return;
	end

	for _, invisible_char in ipairs (cfg.invisible_chars) do
		local char_name = invisible_char[1];									-- the character or group name
		local pattern = invisible_char[2];										-- the pattern used to find it
		position, _, capture = mw.ustring.find (v, pattern);					-- see if the parameter value contains characters that match the pattern
		
		if position and (cfg.invisible_defs.zwj == capture) then				-- if we found a zero-width joiner character
			if mw.ustring.find (v, cfg.indic_script) then						-- it's ok if one of the Indic scripts
				position = nil;													-- unset position
			elseif cfg.emoji[mw.ustring.codepoint (v, position+1)] then			-- is zwj followed by a character listed in emoji{}?
				position = nil;													-- unset position
			end
		end
		
		if position then
			if 'nowiki' == capture or 'math' == capture or						-- nowiki and math stripmarkers (not an error condition)
				('templatestyles' == capture and utilities.in_array (param, {'id', 'quote'})) then	-- templatestyles stripmarker allowed in these parameters
					stripmarker = true;											-- set a flag
			elseif true == stripmarker and cfg.invisible_defs.del == capture then	-- because stripmakers begin and end with the delete char, assume that we've found one end of a stripmarker
				position = nil;													-- unset
			else
				local err_msg;
				if capture and not (cfg.invisible_defs.del == capture or cfg.invisible_defs.zwj == capture) then
					err_msg = capture .. ' ' .. char_name;
				else
					err_msg = char_name .. ' ' .. 'character';
				end

				table.insert (z.message_tail, {utilities.set_message ('err_invisible_char', {err_msg, utilities.wrap_style ('parameter', param), position}, true)});	-- add error message
				return;															-- and done with this parameter
			end
		end
	end
end


--[[-------------------< A R G U M E N T _ W R A P P E R >----------------------

Argument wrapper.  This function provides support for argument mapping defined
in the configuration file so that multiple names can be transparently aliased to
single internal variable.

]]

local function argument_wrapper ( args )
	local origin = {};
	
	return setmetatable({
		ORIGIN = function ( self, k )
			local dummy = self[k];												-- force the variable to be loaded.
			return origin[k];
		end
	},
	{
		__index = function ( tbl, k )
			if origin[k] ~= nil then
				return nil;
			end
			
			local args, list, v = args, cfg.aliases[k];
			
			if type( list ) == 'table' then
				v, origin[k] = utilities.select_one ( args, list, 'err_redundant_parameters' );
				if origin[k] == nil then
					origin[k] = '';												-- Empty string, not nil
				end
			elseif list ~= nil then
				v, origin[k] = args[list], list;
			else
				-- maybe let through instead of raising an error?
				-- v, origin[k] = args[k], k;
				error( cfg.messages['unknown_argument_map'] .. ': ' .. k);
			end
			
			-- Empty strings, not nil;
			if v == nil then
				v = '';
				origin[k] = '';
			end
			
			tbl = rawset( tbl, k, v );
			return v;
		end,
	});
end


--[[--------------------------< N O W R A P _ D A T E >-------------------------

When date is YYYY-MM-DD format wrap in nowrap span: <span ...>YYYY-MM-DD</span>.
When date is DD MMMM YYYY or is MMMM DD, YYYY then wrap in nowrap span:
<span ...>DD MMMM</span> YYYY or <span ...>MMMM DD,</span> YYYY

DOES NOT yet support MMMM YYYY or any of the date ranges.

]]

local function nowrap_date (date)
	local cap = '';
	local cap2 = '';

	if date:match("^%d%d%d%d%-%d%d%-%d%d$") then
		date = utilities.substitute (cfg.presentation['nowrap1'], date);
	
	elseif date:match("^%a+%s*%d%d?,%s+%d%d%d%d$") or date:match ("^%d%d?%s*%a+%s+%d%d%d%d$") then
		cap, cap2 = string.match (date, "^(.*)%s+(%d%d%d%d)$");
		date = utilities.substitute (cfg.presentation['nowrap2'], {cap, cap2});
	end
	
	return date;
end


--[[--------------------------< S E T _ T I T L E T Y P E >---------------------

This function sets default title types (equivalent to the citation including
|type=<default value>) for those templates that have defaults. Also handles the
special case where it is desirable to omit the title type from the rendered citation
(|type=none).

]]

local function set_titletype (cite_class, title_type)
	if utilities.is_set (title_type) then
		if 'none' == cfg.keywords_xlate[title_type] then
			title_type = '';													-- if |type=none then type parameter not displayed
		end
		return title_type;														-- if |type= has been set to any other value use that value
	end

	return cfg.title_types [cite_class] or '';									-- set template's default title type; else empty string for concatenation
end


--[[--------------------------< H Y P H E N _ T O _ D A S H >--------------------------------------------------

Converts a hyphen to a dash under certain conditions.  The hyphen must separate
like items; unlike items are returned unmodified.  These forms are modified:
	letter - letter (A - B)
	digit - digit (4-5)
	digit separator digit - digit separator digit (4.1-4.5 or 4-1-4-5)
	letterdigit - letterdigit (A1-A5) (an optional separator between letter and
		digit is supported – a.1-a.5 or a-1-a-5)
	digitletter - digitletter (5a - 5d) (an optional separator between letter and
		digit is supported – 5.a-5.d or 5-a-5-d)

any other forms are returned unmodified.

str may be a comma- or semicolon-separated list

]]

local function hyphen_to_dash( str )
	if not utilities.is_set (str) then
		return str;
	end

	local accept; -- Boolean

	str = str:gsub ('&[nm]dash;', {['&ndash;'] = '–', ['&mdash;'] = '—'});		-- replace &mdash; and &ndash; entities with their characters; semicolon mucks up the text.split
	str = str:gsub ('&#45;', '-'); -- replace HTML numeric entity with hyphen character

	str = str:gsub ('&nbsp;', ' '); -- replace &nbsp; entity with generic keyboard space character
	
	local out = {};
	local list = mw.text.split (str, '%s*[,;]%s*');								-- split str at comma or semicolon separators if there are any

	for _, item in ipairs (list) do												-- for each item in the list
		item, accept = utilities.has_accept_as_written (item);					-- remove accept-this-as-written markup when it wraps all of item
		if not accept and mw.ustring.match (item, '^%w*[%.%-]?%w+%s*[%-–—]%s*%w*[%.%-]?%w+$') then	-- if a hyphenated range or has endash or emdash separators
			if item:match ('^%a+[%.%-]?%d+%s*%-%s*%a+[%.%-]?%d+$') or			-- letterdigit hyphen letterdigit (optional separator between letter and digit)
				item:match ('^%d+[%.%-]?%a+%s*%-%s*%d+[%.%-]?%a+$') or			-- digitletter hyphen digitletter (optional separator between digit and letter)
				item:match ('^%d+[%.%-]%d+%s*%-%s*%d+[%.%-]%d+$') or			-- digit separator digit hyphen digit separator digit
				item:match ('^%d+%s*%-%s*%d+$') or								-- digit hyphen digit
				item:match ('^%a+%s*%-%s*%a+$') then							-- letter hyphen letter
					item = item:gsub ('(%w*[%.%-]?%w+)%s*%-%s*(%w*[%.%-]?%w+)', '%1–%2');	-- replace hyphen, remove extraneous space characters
			else
				item = mw.ustring.gsub (item, '%s*[–—]%s*', '–');				-- for endash or emdash separated ranges, replace em with en, remove extraneous whitespace
			end
		end
		table.insert (out, item);												-- add the (possibly modified) item to the output table
	end

	local temp_str = '';														-- concatenate the output table into a comma separated string
	temp_str, accept = utilities.has_accept_as_written (table.concat (out, ', ')); -- remove accept-this-as-written markup when it wraps all of concatenated out
	if accept then
		temp_str = utilities.has_accept_as_written (str);						-- when global markup removed, return original str; do it this way to suppress boolean second return value
		return temp_str;
	else
		return temp_str;														-- else, return assembled temp_str
	end
end


--[[--------------------------< S A F E _ J O I N >-----------------------------

Joins a sequence of strings together while checking for duplicate separation characters.

]]

local function safe_join( tbl, duplicate_char )
	local f = {};																-- create a function table appropriate to type of 'duplicate character'
		if 1 == #duplicate_char then											-- for single byte ASCII characters use the string library functions
			f.gsub = string.gsub
			f.match = string.match
			f.sub = string.sub
		else																	-- for multi-byte characters use the ustring library functions
			f.gsub = mw.ustring.gsub
			f.match = mw.ustring.match
			f.sub = mw.ustring.sub
		end

	local str = '';																-- the output string
	local comp = '';															-- what does 'comp' mean?
	local end_chr = '';
	local trim;
	for _, value in ipairs( tbl ) do
		if value == nil then value = ''; end
		
		if str == '' then														-- if output string is empty
			str = value;														-- assign value to it (first time through the loop)
		elseif value ~= '' then
			if value:sub(1, 1) == '<' then										-- special case of values enclosed in spans and other markup.
				comp = value:gsub( "%b<>", "" );								-- remove HTML markup (<span>string</span> -> string)
			else
				comp = value;
			end
																				-- typically duplicate_char is sepc
			if f.sub(comp, 1, 1) == duplicate_char then							-- is first character same as duplicate_char? why test first character?
																				--   Because individual string segments often (always?) begin with terminal punct for the
																				--   preceding segment: 'First element' .. 'sepc next element' .. etc.?
				trim = false;
				end_chr = f.sub(str, -1, -1);									-- get the last character of the output string
				-- str = str .. "<HERE(enchr=" .. end_chr .. ")"				-- debug stuff?
				if end_chr == duplicate_char then								-- if same as separator
					str = f.sub(str, 1, -2);									-- remove it
				elseif end_chr == "'" then										-- if it might be wiki-markup
					if f.sub(str, -3, -1) == duplicate_char .. "''" then		-- if last three chars of str are sepc'' 
						str = f.sub(str, 1, -4) .. "''";						-- remove them and add back ''
					elseif  f.sub(str, -5, -1) == duplicate_char .. "]]''" then	-- if last five chars of str are sepc]]'' 
						trim = true;											-- why? why do this and next differently from previous?
					elseif f.sub(str, -4, -1) == duplicate_char .. "]''" then	-- if last four chars of str are sepc]'' 
						trim = true;											-- same question
					end
				elseif end_chr == "]" then										-- if it might be wiki-markup
					if f.sub(str, -3, -1) == duplicate_char .. "]]" then		-- if last three chars of str are sepc]] wikilink 
						trim = true;
					elseif f.sub(str, -3, -1) == duplicate_char .. '"]' then	-- if last three chars of str are sepc"] quoted external link 
						trim = true;
					elseif  f.sub(str, -2, -1) == duplicate_char .. "]" then	-- if last two chars of str are sepc] external link
						trim = true;
					elseif f.sub(str, -4, -1) == duplicate_char .. "'']" then	-- normal case when |url=something & |title=Title.
						trim = true;
					end
				elseif end_chr == " " then										-- if last char of output string is a space
					if f.sub(str, -2, -1) == duplicate_char .. " " then			-- if last two chars of str are <sepc><space>
						str = f.sub(str, 1, -3);								-- remove them both
					end
				end

				if trim then
					if value ~= comp then 										-- value does not equal comp when value contains HTML markup
						local dup2 = duplicate_char;
						if f.match(dup2, "%A" ) then dup2 = "%" .. dup2; end	-- if duplicate_char not a letter then escape it
						
						value = f.gsub(value, "(%b<>)" .. dup2, "%1", 1 )		-- remove duplicate_char if it follows HTML markup
					else
						value = f.sub(value, 2, -1 );							-- remove duplicate_char when it is first character
					end
				end
			end
			str = str .. value; 												-- add it to the output string
		end
	end
	return str;
end


--[[--------------------------< I S _ S U F F I X >-----------------------------

returns true is suffix is properly formed Jr, Sr, or ordinal in the range 1–9.
Puncutation not allowed.

]]

local function is_suffix (suffix)
	if utilities.in_array (suffix, {'Jr', 'Sr', 'Jnr', 'Snr', '1st', '2nd', '3rd'}) or suffix:match ('^%dth$') then
		return true;
	end
	return false;
end


--[[--------------------< I S _ G O O D _ V A N C _ N A M E >-------------------

For Vancouver style, author/editor names are supposed to be rendered in Latin
(read ASCII) characters.  When a name uses characters that contain diacritical
marks, those characters are to be converted to the corresponding Latin
character. When a name is written using a non-Latin alphabet or logogram, that
name is to be transliterated into Latin characters. The module doesn't do this
so editors may/must.

This test allows |first= and |last= names to contain any of the letters defined
in the four Unicode Latin character sets
	[http://www.unicode.org/charts/PDF/U0000.pdf C0 Controls and Basic Latin] 0041–005A, 0061–007A
	[http://www.unicode.org/charts/PDF/U0080.pdf C1 Controls and Latin-1 Supplement] 00C0–00D6, 00D8–00F6, 00F8–00FF
	[http://www.unicode.org/charts/PDF/U0100.pdf Latin Extended-A] 0100–017F
	[http://www.unicode.org/charts/PDF/U0180.pdf Latin Extended-B] 0180–01BF, 01C4–024F

|lastn= also allowed to contain hyphens, spaces, and apostrophes.
	(http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35029/)
|firstn= also allowed to contain hyphens, spaces, apostrophes, and periods

This original test:
	if nil == mw.ustring.find (last, "^[A-Za-zÀ-ÖØ-öø-ƿDŽ-ɏ%-%s%']*$")
	or nil == mw.ustring.find (first, "^[A-Za-zÀ-ÖØ-öø-ƿDŽ-ɏ%-%s%'%.]+[2-6%a]*$") then
was written outside of the code editor and pasted here because the code editor
gets confused between character insertion point and cursor position. The test has
been rewritten to use decimal character escape sequence for the individual bytes
of the Unicode characters so that it is not necessary to use an external editor
to maintain this code.

	\195\128-\195\150 – À-Ö (U+00C0–U+00D6 – C0 controls)
	\195\152-\195\182 – Ø-ö (U+00D8-U+00F6 – C0 controls)
	\195\184-\198\191 – ø-ƿ (U+00F8-U+01BF – C0 controls, Latin extended A & B)
	\199\132-\201\143 – DŽ-ɏ (U+01C4-U+024F – Latin extended B)

]]

local function is_good_vanc_name (last, first, suffix, position)
	if not suffix then
		if first:find ('[,%s]') then											-- when there is a space or comma, might be first name/initials + generational suffix
			first = first:match ('(.-)[,%s]+');									-- get name/initials
			suffix = first:match ('[,%s]+(.+)$');								-- get generational suffix
		end
	end
	if utilities.is_set (suffix) then
		if not is_suffix (suffix) then
			add_vanc_error (cfg.err_msg_supl.suffix, position);
			return false;														-- not a name with an appropriate suffix
		end
	end
	if nil == mw.ustring.find (last, "^[A-Za-z\195\128-\195\150\195\152-\195\182\195\184-\198\191\199\132-\201\143%-%s%']*$") or
		nil == mw.ustring.find (first, "^[A-Za-z\195\128-\195\150\195\152-\195\182\195\184-\198\191\199\132-\201\143%-%s%'%.]*$") then
			add_vanc_error (cfg.err_msg_supl['non-Latin char'], position);
			return false;														-- not a string of Latin characters; Vancouver requires Romanization
	end;
	return true;
end


--[[--------------------------< R E D U C E _ T O _ I N I T I A L S >------------------------------------------

Attempts to convert names to initials in support of |name-list-style=vanc.  

Names in |firstn= may be separated by spaces or hyphens, or for initials, a period.
See http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35062/.

Vancouver style requires family rank designations (Jr, II, III, etc.) to be rendered
as Jr, 2nd, 3rd, etc.  See http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35085/.
This code only accepts and understands generational suffix in the Vancouver format
because Roman numerals look like, and can be mistaken for, initials.

This function uses ustring functions because firstname initials may be any of the
Unicode Latin characters accepted by is_good_vanc_name ().

]]

local function reduce_to_initials(first, position)
	local name, suffix = mw.ustring.match(first, "^(%u+) ([%dJS][%drndth]+)$");

	if not name then															-- if not initials and a suffix
		name = mw.ustring.match(first, "^(%u+)$");								-- is it just initials?
	end

	if name then																-- if first is initials with or without suffix
		if 3 > mw.ustring.len (name) then										-- if one or two initials
			if suffix then														-- if there is a suffix
				if is_suffix (suffix) then										-- is it legitimate?
					return first;												-- one or two initials and a valid suffix so nothing to do
				else
					add_vanc_error (cfg.err_msg_supl.suffix, position);			-- one or two initials with invalid suffix so error message
					return first;												-- and return first unmolested
				end
			else
				return first;													-- one or two initials without suffix; nothing to do
			end
		end
	end																			-- if here then name has 3 or more uppercase letters so treat them as a word

	local initials, names = {}, {};												-- tables to hold name parts and initials
	local i = 1;																-- counter for number of initials

	names = mw.text.split (first, '[%s,]+');									-- split into a table of names and possible suffix

	while names[i] do															-- loop through the table
		if 1 < i and names[i]:match ('[%dJS][%drndth]+%.?$') then				-- if not the first name, and looks like a suffix (may have trailing dot)
			names[i] = names[i]:gsub ('%.', '');								-- remove terminal dot if present
			if is_suffix (names[i]) then										-- if a legitimate suffix
				table.insert (initials, ' ' .. names[i]);						-- add a separator space, insert at end of initials table
				break;															-- and done because suffix must fall at the end of a name
			end																	-- no error message if not a suffix; possibly because of Romanization
		end
		if 3 > i then
			table.insert (initials, mw.ustring.sub(names[i], 1, 1));			-- insert the initial at end of initials table
		end
		i = i + 1;																-- bump the counter
	end
			
	return table.concat(initials)												-- Vancouver format does not include spaces.
end


--[[--------------------------< L I S T _ P E O P L E >--------------------------

Formats a list of people (authors, contributors, editors, interviewers, translators) 

names in the list will be linked when
	|<name>-link= has a value
	|<name>-mask- does NOT have a value; masked names are presumed to have been
		rendered previously so should have been linked there

when |<name>-mask=0, the associated name is not rendered

]]

local function list_people (control, people, etal)
	local sep;
	local namesep;
	local format = control.format;
	local maximum = control.maximum;
	local name_list = {};

	if 'vanc' == format then													-- Vancouver-like name styling?
		sep = cfg.presentation['sep_nl_vanc'];									-- name-list separator between names is a comma
		namesep = cfg.presentation['sep_name_vanc'];							-- last/first separator is a space
	else
		sep = cfg.presentation['sep_nl'];										-- name-list separator between names is a semicolon
		namesep = cfg.presentation['sep_name'];									-- last/first separator is <comma><space>
	end
	
	if sep:sub (-1, -1) ~= " " then sep = sep .. " " end
	if utilities.is_set (maximum) and maximum < 1 then return "", 0; end		-- returned 0 is for EditorCount; not used for other names
	
	for i, person in ipairs (people) do
		if utilities.is_set (person.last) then
			local mask = person.mask;
			local one;
			local sep_one = sep;

			if utilities.is_set (maximum) and i > maximum then
				etal = true;
				break;
			end
			
			if mask then
				local n = tonumber (mask);										-- convert to a number if it can be converted; nil else
				if n then
					one = 0 ~= n and string.rep("&mdash;", n) or nil;			-- make a string of (n > 0) mdashes, nil else, to replace name
					person.link = nil;											-- don't create link to name if name is replaces with mdash string or has been set nil
				else
					one = mask;													-- replace name with mask text (must include name-list separator)
					sep_one = " ";												-- modify name-list separator
				end
			else
				one = person.last;												-- get surname
				local first = person.first										-- get given name
				if utilities.is_set (first) then
					if ("vanc" == format) then									-- if Vancouver format
						one = one:gsub ('%.', '');								-- remove periods from surnames (http://www.ncbi.nlm.nih.gov/books/NBK7271/box/A35029/)
						if not person.corporate and is_good_vanc_name (one, first, nil, i) then		-- and name is all Latin characters; corporate authors not tested
							first = reduce_to_initials (first, i);				-- attempt to convert first name(s) to initials
						end
					end
					one = one .. namesep .. first;
				end
			end
			if utilities.is_set (person.link) then
				one = utilities.make_wikilink (person.link, one);				-- link author/editor
			end
			if one then															-- if <one> has a value (name, mdash replacement, or mask text replacement)
				table.insert (name_list, one);									-- add it to the list of names
				table.insert (name_list, sep_one);								-- add the proper name-list separator
			end
		end
	end

	local count = #name_list / 2;												-- (number of names + number of separators) divided by 2
	if 0 < count then 
		if 1 < count and not etal then
			if 'amp' == format then
				name_list[#name_list-2] = " & ";								-- replace last separator with ampersand text
			elseif 'and' == format then
				if 2 == count then
					name_list[#name_list-2] = cfg.presentation.sep_nl_and;		-- replace last separator with 'and' text
				else
					name_list[#name_list-2] = cfg.presentation.sep_nl_end;		-- replace last separator with '(sep) and' text
				end
			end
		end
		name_list[#name_list] = nil;											-- erase the last separator
	end

	local result = table.concat (name_list);									-- construct list
	if etal and utilities.is_set (result) then									-- etal may be set by |display-authors=etal but we might not have a last-first list
		result = result .. sep .. ' ' .. cfg.messages['et al'];					-- we've got a last-first list and etal so add et al.
	end
	
	return result, count;														-- return name-list string and count of number of names (count used for editor names only)
end

--[[--------------------< M A K E _ C I T E R E F _ I D >-----------------------

Generates a CITEREF anchor ID if we have at least one name or a date.  Otherwise
returns an empty string.

namelist is one of the contributor-, author-, or editor-name lists chosen in that
order.  year is Year or anchor_year.

]]

local function make_citeref_id (namelist, year)
	local names={};							-- a table for the one to four names and year
	for i,v in ipairs (namelist) do			-- loop through the list and take up to the first four last names
		names[i] = v.last
		if i == 4 then break end			-- if four then done
	end
	table.insert (names, year);				-- add the year at the end
	local id = table.concat(names);			-- concatenate names and year for CITEREF id
	if utilities.is_set (id) then			-- if concatenation is not an empty string
		return "CITEREF" .. id;				-- add the CITEREF portion
	else
		return '';							-- return an empty string; no reason to include CITEREF id in this citation
	end
end


--[[---------------------< N A M E _ H A S _ E T A L >--------------------------

Evaluates the content of name parameters (author, editor, etc.) for variations on
the theme of et al.  If found, the et al. is removed, a flag is set to true and
the function returns the modified name and the flag.

This function never sets the flag to false but returns its previous state because
it may have been set by previous passes through this function or by the associated
|display-<names>=etal parameter

]]

local function name_has_etal (name, etal, nocat, param)

	if utilities.is_set (name) then												-- name can be nil in which case just return
		local patterns = cfg.et_al_patterns; 									-- get patterns from configuration
		
		for _, pattern in ipairs (patterns) do									-- loop through all of the patterns
			if name:match (pattern) then										-- if this 'et al' pattern is found in name
				name = name:gsub (pattern, '');									-- remove the offending text
				etal = true;													-- set flag (may have been set previously here or by |display-<names>=etal)
				if not nocat then												-- no categorization for |vauthors=
					table.insert( z.message_tail, {utilities.set_message ('err_etal', {param})});	-- and set an error if not added
				end
			end
		end
	end

	return name, etal;
end


--[[---------------------< N A M E _ I S _ N U M E R I C >----------------------

Add maint cat when name parameter value does not contain letters.  Does not catch
mixed alphanumeric names so |last=A. Green (1922-1987) does not get caught in the
current version of this test but |first=(1888) is caught.

returns nothing

]]

local function name_is_numeric (name, list_name)
	if utilities.is_set (name) then
		if mw.ustring.match (name, '^[%A]+$') then								-- when name does not contain any letters
			utilities.set_message ('maint_numeric_names', cfg.special_case_translation [list_name]);	-- add a maint cat for this template
		end
	end
end


--[[-------------------< N A M E _ H A S _ E D _ M A R K U P >------------------

Evaluates the content of author and editor parameters for extraneous editor annotations:
ed, ed., eds, (Ed.), etc. These annotations do not belong in author parameters and
are redundant in editor parameters.  If found, the function adds the editor markup
maintenance category.

returns nothing

]]

local function name_has_ed_markup (name, list_name)
	local patterns = cfg.editor_markup_patterns;								-- get patterns from configuration

	if utilities.is_set (name) then
		for _, pattern in ipairs (patterns) do									-- spin through patterns table and
			if name:match (pattern) then
				utilities.set_message ('maint_extra_text_names', cfg.special_case_translation [list_name]);	-- add a maint cat for this template
				break;
			end
		end
	end
end


--[[-----------------< N A M E _ H A S _ M U L T _ N A M E S >------------------

Evaluates the content of last/surname (authors etc.) parameters for multiple names.
Multiple names are indicated if there is more than one comma or any "unescaped"
semicolons. Escaped semicolons are ones used as part of selected HTML entities.
If the condition is met, the function adds the multiple name maintenance category.

returns nothing

]]

local function name_has_mult_names (name, list_name)
	local _, commas, semicolons, nbsps;
	if utilities.is_set (name) then
		_, commas = name:gsub (',', '');										-- count the number of commas
		_, semicolons = name:gsub (';', '');									-- count the number of semicolons
		-- nbsps probably should be its own separate count rather than merged in
		-- some way with semicolons because Lua patterns do not support the
		-- grouping operator that regex does, which means there is no way to add
		-- more entities to escape except by adding more counts with the new
		-- entities
		_, nbsps = name:gsub ('&nbsp;','');										-- count nbsps
		
		-- There is exactly 1 semicolon per &nbsp; entity, so subtract nbsps
		-- from semicolons to 'escape' them. If additional entities are added,
		-- they also can be subtracted.
		if 1 < commas or 0 < (semicolons - nbsps) then
			utilities.set_message ('maint_mult_names', cfg.special_case_translation [list_name]);	-- add a maint message
		end
	end
end


--[[------------------------< N A M E _ C H E C K S >---------------------------

This function calls various name checking functions used to validate the content
of the various name-holding parameters.

]]

local function name_checks (last, first, list_name)
	local accept_name;

	if utilities.is_set (last) then
		last, accept_name = utilities.has_accept_as_written (last);				-- remove accept-this-as-written markup when it wraps all of <last>
		
		if not accept_name then													-- <last> not wrapped in accept-as-written markup
			name_has_mult_names (last, list_name);								-- check for multiple names in the parameter (last only)
			name_has_ed_markup (last, list_name);								-- check for extraneous 'editor' annotation
			name_is_numeric (last, list_name);									-- check for names that are composed of digits and punctuation
		end
	end

	if utilities.is_set (first) then
		first, accept_name = utilities.has_accept_as_written (first);			-- remove accept-this-as-written markup when it wraps all of <first>

		if not accept_name then													-- <first> not wrapped in accept-as-written markup
			name_has_ed_markup (first, list_name);								-- check for extraneous 'editor' annotation
			name_is_numeric (first, list_name);									-- check for names that are composed of digits and punctuation
		end
	end

	return last, first;															-- done
end


--[[----------------------< E X T R A C T _ N A M E S >-------------------------
Gets name list from the input arguments

Searches through args in sequential order to find |lastn= and |firstn= parameters
(or their aliases), and their matching link and mask parameters. Stops searching
when both |lastn= and |firstn= are not found in args after two sequential attempts:
found |last1=, |last2=, and |last3= but doesn't find |last4= and |last5= then the
search is done.

This function emits an error message when there is a |firstn= without a matching
|lastn=.  When there are 'holes' in the list of last names, |last1= and |last3=
are present but |last2= is missing, an error message is emitted. |lastn= is not
required to have a matching |firstn=.

When an author or editor parameter contains some form of 'et al.', the 'et al.'
is stripped from the parameter and a flag (etal) returned that will cause list_people()
to add the static 'et al.' text from Module:Citation/CS1/Configuration.  This keeps
'et al.' out of the template's metadata.  When this occurs, an error is emitted.

]]

local function extract_names(args, list_name)
	local names = {};															-- table of names
	local last;																	-- individual name components
	local first;
	local link;
	local mask;
	local i = 1;																-- loop counter/indexer
	local n = 1;																-- output table indexer
	local count = 0;															-- used to count the number of times we haven't found a |last= (or alias for authors, |editor-last or alias for editors)
	local etal = false;															-- return value set to true when we find some form of et al. in an author parameter

	local last_alias, first_alias, link_alias;									-- selected parameter aliases used in error messaging
	while true do
		last, last_alias = utilities.select_one ( args, cfg.aliases[list_name .. '-Last'], 'err_redundant_parameters', i );		-- search through args for name components beginning at 1
		first, first_alias = utilities.select_one ( args, cfg.aliases[list_name .. '-First'], 'err_redundant_parameters', i );
		link, link_alias = utilities.select_one ( args, cfg.aliases[list_name .. '-Link'], 'err_redundant_parameters', i );
		mask = utilities.select_one ( args, cfg.aliases[list_name .. '-Mask'], 'err_redundant_parameters', i );

		last, etal = name_has_etal (last, etal, false, last_alias);				-- find and remove variations on et al.
		first, etal = name_has_etal (first, etal, false, first_alias);			-- find and remove variations on et al.
		last, first = name_checks (last, first, list_name);						-- multiple names, extraneous annotation, etc. checks
		
		if first and not last then												-- if there is a firstn without a matching lastn
			local alias = first_alias:find ('given', 1, true) and 'given' or 'first';	-- get first or given form of the alias
			table.insert (z.message_tail, { utilities.set_message ( 'err_first_missing_last', {
				first_alias,													-- param name of alias missing its mate
				first_alias:gsub (alias, {['first'] = 'last', ['given'] = 'surname'}),	-- make param name appropriate to the alias form
				}, true ) } );													-- add this error message
		elseif not first and not last then										-- if both firstn and lastn aren't found, are we done?
			count = count + 1;													-- number of times we haven't found last and first
			if 2 <= count then													-- two missing names and we give up
				break;															-- normal exit or there is a two-name hole in the list; can't tell which
			end
		else																	-- we have last with or without a first
			local result;
			link = link_title_ok (link, link_alias, last, last_alias);			-- check for improper wiki-markup
			if first then
				link = link_title_ok (link, link_alias, first, first_alias);	-- check for improper wiki-markup
			end

			names[n] = {last = last, first = first, link = link, mask = mask, corporate = false};	-- add this name to our names list (corporate for |vauthors= only)
			n = n + 1;															-- point to next location in the names table
			if 1 == count then													-- if the previous name was missing
				table.insert( z.message_tail, { utilities.set_message ( 'err_missing_name', {list_name:match ("(%w+)List"):lower(), i - 1}, true ) } );	-- add this error message
			end
			count = 0;															-- reset the counter, we're looking for two consecutive missing names
		end
		i = i + 1;																-- point to next args location
	end
	
	return names, etal;															-- all done, return our list of names and the etal flag
end


--[[---------------------< G E T _ I S O 6 3 9 _ C O D E >----------------------

Validates language names provided in |language= parameter if not an ISO639-1 or 639-2 code.

Returns the language name and associated two- or three-character code.  Because
case of the source may be incorrect or different from the case that WikiMedia uses,
the name comparisons are done in lower case and when a match is found, the Wikimedia
version (assumed to be correct) is returned along with the code.  When there is no
match, we return the original language name string.

mw.language.fetchLanguageNames(<local wiki language>, 'all') returns a list of
languages that in some cases may include extensions. For example, code 'cbk-zam'
and its associated name 'Chavacano de Zamboanga' (MediaWiki does not support
code 'cbk' or name 'Chavacano'.  Most (all?) of these languages are not used a
'language' codes per se, rather they are used as sub-domain names: cbk-zam.wikipedia.org.
A list of language names and codes supported by fetchLanguageNames() can be found
at Template:Citation Style documentation/language/doc

Names that are included in the list will be found if that name is provided in the
|language= parameter.  For example, if |language=Chavacano de Zamboanga, that name
will be found with the associated code 'cbk-zam'.  When names are found and the
associated code is not two or three characters, this function returns only the
WikiMedia language name.

Some language names have multiple entries under different codes:
	Aromanian has code rup and code roa-rup
When this occurs, this function returns the language name and the 2- or 3-character code

Adapted from code taken from Module:Check ISO 639-1.

]]

local function get_iso639_code (lang, this_wiki_code)
	if cfg.lang_name_remap[lang:lower()] then									-- if there is a remapped name (because MediaWiki uses something that we don't think is correct)
		return cfg.lang_name_remap[lang:lower()][1], cfg.lang_name_remap[lang:lower()][2];	-- for this language 'name', return a possibly new name and appropriate code
	end

	local ietf_code;															-- because some languages have both IETF-like codes and ISO 639-like codes
	local ietf_name;
	
	local langlc = mw.ustring.lower (lang);										-- lower-case version for comparisons

	for code, name in pairs (cfg.languages) do									-- scan the list to see if we can find our language
		if langlc == mw.ustring.lower (name) then
			if 2 == #code or 3 == #code then									-- two- or three-character codes only; IETF extensions not supported
				return name, code;												-- so return the name and the code
			end
			ietf_code = code;													-- remember that we found an IETF-like code and save its name
			ietf_name = name;													-- but keep looking for a 2- or 3-char code
		end
	end
																				-- didn't find name with 2- or 3-char code; if IETF-like code found return
	return ietf_code and ietf_name or lang;										-- associated name; return original language text else
end


--[[-------------------< L A N G U A G E _ P A R A M E T E R >------------------

Gets language name from a provided two- or three-character ISO 639 code.  If a code
is recognized by MediaWiki, use the returned name; if not, then use the value that
was provided with the language parameter.

When |language= contains a recognized language (either code or name), the page is
assigned to the category for that code: Category:Norwegian-language sources (no).
For valid three-character code languages, the page is assigned to the single category
for '639-2' codes: Category:CS1 ISO 639-2 language sources.

Languages that are the same as the local wiki are not categorized.  MediaWiki does
not recognize three-character equivalents of two-character codes: code 'ar' is
recognized but code 'ara' is not.

This function supports multiple languages in the form |language=nb, French, th
where the language names or codes are separated from each other by commas with
optional space characters.

]]

local function language_parameter (lang)
	local code;																	-- the two- or three-character language code
	local name;																	-- the language name
	local language_list = {};													-- table of language names to be rendered
	local names_table = {};														-- table made from the value assigned to |language=

	local this_wiki_name = mw.language.fetchLanguageName (cfg.this_wiki_code, cfg.this_wiki_code);	-- get this wiki's language name

	names_table = mw.text.split (lang, '%s*,%s*');								-- names should be a comma separated list

	for _, lang in ipairs (names_table) do										-- reuse lang
		name = cfg.lang_code_remap[lang:lower()];								-- first see if this is a code that is not supported by MediaWiki but is in remap

		if name then															-- there was a remapped code so
			if not lang:match ('^%a%a%a?%-x%-%a+$') then						-- if not a private IETF tag
				lang = lang:gsub ('^(%a%a%a?)%-.*', '%1');						-- strip IETF tags from code
			end
		else
			lang = lang:gsub ('^(%a%a%a?)%-.*', '%1');							-- strip any IETF-like tags from code
			if 2 == lang:len() or 3 == lang:len() then							-- if two-or three-character code
				name = mw.language.fetchLanguageName (lang:lower(), cfg.this_wiki_code);	-- get language name if |language= is a proper code
			end
		end

		if utilities.is_set (name) then											-- if |language= specified a valid code
			code = lang:lower();												-- save it
		else
			name, code = get_iso639_code (lang, cfg.this_wiki_code);			-- attempt to get code from name (assign name here so that we are sure of proper capitalization)
		end
	
		if utilities.is_set (code) then											-- only 2- or 3-character codes
			name = cfg.lang_code_remap[code] or name;							-- override wikimedia when they misuse language codes/names

			if cfg.this_wiki_code ~= code then									-- when the language is not the same as this wiki's language
				if 2 == code:len() then											-- and is a two-character code
					utilities.add_prop_cat ('foreign_lang_source' .. code, {name, code});	-- categorize it; code appended to allow for multiple language categorization
				else															-- or is a recognized language (but has a three-character code)
					utilities.add_prop_cat ('foreign_lang_source_2' .. code, {code});		-- categorize it differently TODO: support multiple three-character code categories per cs1|2 template
				end
			elseif cfg.local_lang_cat_enable then								-- when the language and this wiki's language are the same and categorization is enabled
				utilities.add_prop_cat ('local_lang_source', {name, code});		-- categorize it
			end
		else
			utilities.set_message ('maint_unknown_lang');						-- add maint category if not already added
		end
		
		table.insert (language_list, name);
		name = '';																-- so we can reuse it
	end
 
	name = utilities.make_sep_list (#language_list, language_list);

	if this_wiki_name == name then
		return '';																-- if one language and that language is this wiki's return an empty string (no annotation)
	end
	return (" " .. wrap_msg ('language', name));								-- otherwise wrap with '(in ...)'
	--[[ TODO: should only return blank or name rather than full list
	so we can clean up the bunched parenthetical elements Language, Type, Format
	]]
end

--[[-----------------------< S E T _ C S _ S T Y L E >--------------------------
Gets the default CS style configuration for the given mode.
Returns default separator and either postscript as passed in or the default.
In CS1, the default postscript and separator are '.'.
In CS2, the default postscript is the empty string and the default separator is ','.
]]
local function set_cs_style (postscript, mode)
	if utilities.is_set(postscript) then
		-- emit a maintenance message if user postscript is the default cs1 postscript
		-- we catch the opposite case for cs2 in set_style
		if mode == 'cs1' and postscript == cfg.presentation['ps_' .. mode] then
			utilities.set_message ('maint_postscript');
		end
	else
		postscript = cfg.presentation['ps_' .. mode];
	end
	return cfg.presentation['sep_' .. mode], postscript;
end

--[[--------------------------< S E T _ S T Y L E >-----------------------------
Sets the separator and postscript styles. Checks the |mode= first and the
#invoke CitationClass second. Removes the postscript if postscript == none.
]]
local function set_style (mode, postscript, cite_class)
	local sep;
	if 'cs2' == mode then
		sep, postscript = set_cs_style (postscript, 'cs2');
	elseif 'cs1' == mode then
		sep, postscript = set_cs_style (postscript, 'cs1');
	elseif 'citation' == cite_class	then
		sep, postscript = set_cs_style (postscript, 'cs2');
	else
		sep, postscript = set_cs_style (postscript, 'cs1');
	end

	if cfg.keywords_xlate[postscript:lower()] == 'none' then
		-- emit a maintenance message if user postscript is the default cs2 postscript
		-- we catch the opposite case for cs1 in set_cs_style
		if 'cs2' == mode or 'citation' == cite_class then
			utilities.set_message ('maint_postscript');
		end
		postscript = '';
	end
	
	return sep, postscript
end

--[=[-------------------------< I S _ P D F >-----------------------------------

Determines if a URL has the file extension that is one of the PDF file extensions
used by [[MediaWiki:Common.css]] when applying the PDF icon to external links.

returns true if file extension is one of the recognized extensions, else false

]=]

local function is_pdf (url)
	return url:match ('%.pdf$') or url:match ('%.PDF$') or
		url:match ('%.pdf[%?#]') or url:match ('%.PDF[%?#]') or
		url:match ('%.PDF&#035') or url:match ('%.pdf&#035');
end


--[[--------------------------< S T Y L E _ F O R M A T >-----------------------

Applies CSS style to |format=, |chapter-format=, etc.  Also emits an error message
if the format parameter does not have a matching URL parameter.  If the format parameter
is not set and the URL contains a file extension that is recognized as a PDF document
by MediaWiki's commons.css, this code will set the format parameter to (PDF) with
the appropriate styling.

]]

local function style_format (format, url, fmt_param, url_param)
	if utilities.is_set (format) then
		format = utilities.wrap_style ('format', format);						-- add leading space, parentheses, resize
		if not utilities.is_set (url) then
			format = format .. ' ' .. utilities.set_message ( 'err_format_missing_url', {fmt_param, url_param} );	-- add an error message
		end
	elseif is_pdf (url) then													-- format is not set so if URL is a PDF file then
		format = utilities.wrap_style ('format', 'PDF');						-- set format to PDF
	else
		format = '';															-- empty string for concatenation
	end
	return format;
end


--[[---------------------< G E T _ D I S P L A Y _ N A M E S >------------------

Returns a number that defines the number of names displayed for author and editor
name lists and a Boolean flag to indicate when et al. should be appended to the name list.

When the value assigned to |display-xxxxors= is a number greater than or equal to zero,
return the number and the previous state of the 'etal' flag (false by default
but may have been set to true if the name list contains some variant of the text 'et al.').

When the value assigned to |display-xxxxors= is the keyword 'etal', return a number
that is one greater than the number of authors in the list and set the 'etal' flag true.
This will cause the list_people() to display all of the names in the name list followed by 'et al.'

In all other cases, returns nil and the previous state of the 'etal' flag.

inputs:
	max: A['DisplayAuthors'] or A['DisplayEditors']; a number or some flavor of etal
	count: #a or #e
	list_name: 'authors' or 'editors'
	etal: author_etal or editor_etal

]]

local function get_display_names (max, count, list_name, etal, param)
	if utilities.is_set (max) then
		if 'etal' == max:lower():gsub("[ '%.]", '') then						-- the :gsub() portion makes 'etal' from a variety of 'et al.' spellings and stylings
			max = count + 1;													-- number of authors + 1 so display all author name plus et al.
			etal = true;														-- overrides value set by extract_names()
		elseif max:match ('^%d+$') then											-- if is a string of numbers
			max = tonumber (max);												-- make it a number
			if max >= count then												-- if |display-xxxxors= value greater than or equal to number of authors/editors
				table.insert( z.message_tail, {utilities.set_message ('err_disp_name', {param, max}, true)});	-- add error message
				max = nil;
			end
		else																	-- not a valid keyword or number
			table.insert( z.message_tail, {utilities.set_message ('err_disp_name', {param, max}, true)});		-- add error message
			max = nil;															-- unset; as if |display-xxxxors= had not been set
		end
	end
	
	return max, etal;
end


--[[----------< E X T R A _ T E X T _ I N _ P A G E _ C H E C K >---------------

Adds error if |page=, |pages=, |quote-page=, |quote-pages= has what appears to be
some form of p. or pp. abbreviation in the first characters of the parameter content.

check page for extraneous p, p., pp, pp., pg, pg. at start of parameter value:
	good pattern: '^P[^%.P%l]' matches when page begins PX or P# but not Px
		      where x and X are letters and # is a digit
	bad pattern:  '^[Pp][PpGg]' matches when page begins pp, pP, Pp, PP, pg, pG, Pg, PG

]]

local function extra_text_in_page_check (val, name)
	if not val:match (cfg.vol_iss_pg_patterns.good_ppattern) then
		for _, pattern in ipairs (cfg.vol_iss_pg_patterns.bad_ppatterns) do		-- spin through the selected sequence table of patterns
			if val:match (pattern) then											-- when a match, error so
				table.insert (z.message_tail, {utilities.set_message ('err_extra_text_pages', {name}, true)}); -- add error message
				return;															-- and done
			end
		end
	end		
end


--[[--------------------------< E X T R A _ T E X T _ I N _ V O L _ I S S _ C H E C K >------------------------

Adds error if |volume= or |issue= has what appears to be some form of redundant 'type' indicator.

For |volume=:
	'V.', or 'Vol.' (with or without the dot) abbreviations or 'Volume' in the first characters of the parameter
	content (all case insensitive). 'V' and 'v' (without the dot) are presumed to be roman numerals so
	are allowed.

For |issue=:
	'No.', 'I.', 'Iss.' (with or without the dot) abbreviations, or 'Issue' in the first characters of the
	parameter content (all case insensitive).
	
Single character values ('v', 'i', 'n') allowed when not followed by separator character ('.', ':', '=', or
whitespace character) – param values are trimmed of whitespace by MediaWiki before delivered to the module.
	
<val> is |volume= or |issue= parameter value
<name> is |volume= or |issue= parameter name for error message
<selector> is 'v' for |volume=, 'i' for |issue=

sets error message on failure; returns nothing

]]

local function extra_text_in_vol_iss_check (val, name, selector)
	if not utilities.is_set (val) then
		return;
	end
	
	local patterns = 'v' == selector and cfg.vol_iss_pg_patterns.vpatterns or cfg.vol_iss_pg_patterns.ipatterns;

	local handler = 'v' == selector and 'err_extra_text_volume' or 'err_extra_text_issue';
	val = val:lower();															-- force parameter value to lower case
	for _, pattern in ipairs (patterns) do										-- spin through the selected sequence table of patterns
		if val:match (pattern) then												-- when a match, error so
			table.insert (z.message_tail, {utilities.set_message (handler, {name}, true)}); -- add error message
			return;																-- and done
		end
	end
end


--[=[-------------------------< G E T _ V _ N A M E _ T A B L E >----------------------------------------------

split apart a |vauthors= or |veditors= parameter.  This function allows for corporate names, wrapped in doubled
parentheses to also have commas; in the old version of the code, the doubled parentheses were included in the
rendered citation and in the metadata.  Individual author names may be wikilinked

	|vauthors=Jones AB, [[E. B. White|White EB]], ((Black, Brown, and Co.))

]=]

local function get_v_name_table (vparam, output_table, output_link_table)
	local name_table = mw.text.split(vparam, "%s*,%s*");						-- names are separated by commas
	local wl_type, label, link;													-- wl_type not used here; just a placeholder
	
	local i = 1;
	
	while name_table[i] do
		if name_table[i]:match ('^%(%(.*[^%)][^%)]$') then						-- first segment of corporate with one or more commas; this segment has the opening doubled parentheses
			local name = name_table[i];
			i = i + 1;															-- bump indexer to next segment
			while name_table[i] do
				name = name .. ', ' .. name_table[i];							-- concatenate with previous segments
				if name_table[i]:match ('^.*%)%)$') then						-- if this table member has the closing doubled parentheses
					break;														-- and done reassembling so
				end
				i = i + 1;														-- bump indexer
			end
			table.insert (output_table, name);									-- and add corporate name to the output table
			table.insert (output_link_table, '');								-- no wikilink
		else
			wl_type, label, link = utilities.is_wikilink (name_table[i]);		-- wl_type is: 0, no wl (text in label variable); 1, [[D]]; 2, [[L|D]]
			table.insert (output_table, label);									-- add this name
			if 1 == wl_type then
				table.insert (output_link_table, label);						-- simple wikilink [[D]]
			else
				table.insert (output_link_table, link);							-- no wikilink or [[L|D]]; add this link if there is one, else empty string
			end
		end
		i = i + 1;
	end	
	return output_table;
end


--[[--------------------------< P A R S E _ V A U T H O R S _ V E D I T O R S >--------------------------------

This function extracts author / editor names from |vauthors= or |veditors= and finds matching |xxxxor-maskn= and
|xxxxor-linkn= in args.  It then returns a table of assembled names just as extract_names() does.

Author / editor names in |vauthors= or |veditors= must be in Vancouver system style. Corporate or institutional names
may sometimes be required and because such names will often fail the is_good_vanc_name() and other format compliance
tests, are wrapped in doubled parentheses ((corporate name)) to suppress the format tests.

Supports generational suffixes Jr, 2nd, 3rd, 4th–6th.

This function sets the Vancouver error when a required comma is missing and when there is a space between an author's initials.

]]

local function parse_vauthors_veditors (args, vparam, list_name)
	local names = {};															-- table of names assembled from |vauthors=, |author-maskn=, |author-linkn=
	local v_name_table = {};
	local v_link_table = {};													-- when name is wikilinked, targets go in this table
	local etal = false;															-- return value set to true when we find some form of et al. vauthors parameter
	local last, first, link, mask, suffix;
	local corporate = false;

	vparam, etal = name_has_etal (vparam, etal, true);							-- find and remove variations on et al. do not categorize (do it here because et al. might have a period)
	v_name_table = get_v_name_table (vparam, v_name_table, v_link_table);		-- names are separated by commas

	for i, v_name in ipairs(v_name_table) do
		first = '';																-- set to empty string for concatenation and because it may have been set for previous author/editor
		local accept_name;
		v_name, accept_name = utilities.has_accept_as_written (v_name);			-- remove accept-this-as-written markup when it wraps all of <v_name>

		if accept_name then
			last = v_name;
			corporate = true;													-- flag used in list_people()
		elseif string.find(v_name, "%s") then
			if v_name:find('[;%.]') then										-- look for commonly occurring punctuation characters; 
				add_vanc_error (cfg.err_msg_supl.punctuation, i);
			end
			local lastfirstTable = {}
			lastfirstTable = mw.text.split(v_name, "%s+")
			first = table.remove(lastfirstTable);								-- removes and returns value of last element in table which should be initials or generational suffix

			if not mw.ustring.match (first, '^%u+$') then						-- mw.ustring here so that later we will catch non-Latin characters
				suffix = first;													-- not initials so assume that whatever we got is a generational suffix
				first = table.remove(lastfirstTable);							-- get what should be the initials from the table
			end
			last = table.concat(lastfirstTable, ' ')							-- returns a string that is the concatenation of all other names that are not initials and generational suffix
			if not utilities.is_set (last) then
				first = '';														-- unset
				last = v_name;													-- last empty because something wrong with first
				add_vanc_error (cfg.err_msg_supl.name, i);
			end
			if mw.ustring.match (last, '%a+%s+%u+%s+%a+') then
				add_vanc_error (cfg.err_msg_supl['missing comma'], i);			-- matches last II last; the case when a comma is missing
			end
			if mw.ustring.match (v_name, ' %u %u$') then						-- this test is in the wrong place TODO: move or replace with a more appropriate test
				add_vanc_error (cfg.err_msg_supl.initials, i);					-- matches a space between two initials
			end
		else
			last = v_name;														-- last name or single corporate name?  Doesn't support multiword corporate names? do we need this?
		end
		
		if utilities.is_set (first) then
			if not mw.ustring.match (first, "^%u?%u$") then						-- first shall contain one or two upper-case letters, nothing else
				add_vanc_error (cfg.err_msg_supl.initials, i);					-- too many initials; mixed case initials (which may be ok Romanization); hyphenated initials
			end
			is_good_vanc_name (last, first, suffix, i);							-- check first and last before restoring the suffix which may have a non-Latin digit
			if utilities.is_set (suffix) then
				first = first .. ' ' .. suffix;									-- if there was a suffix concatenate with the initials
				suffix = '';													-- unset so we don't add this suffix to all subsequent names
			end
		else
			if not corporate then
				is_good_vanc_name (last, '', nil, i);
			end
		end

		link = utilities.select_one ( args, cfg.aliases[list_name .. '-Link'], 'err_redundant_parameters', i ) or v_link_table[i];
		mask = utilities.select_one ( args, cfg.aliases[list_name .. '-Mask'], 'err_redundant_parameters', i );
		names[i] = {last = last, first = first, link = link, mask = mask, corporate = corporate};		-- add this assembled name to our names list
	end
	return names, etal;															-- all done, return our list of names
end


--[[--------------------------< S E L E C T _ A U T H O R _ E D I T O R _ S O U R C E >------------------------

Select one of |authors=, |authorn= / |lastn / firstn=, or |vauthors= as the source of the author name list or
select one of |editorn= / editor-lastn= / |editor-firstn= or |veditors= as the source of the editor name list.

Only one of these appropriate three will be used.  The hierarchy is: |authorn= (and aliases) highest and |authors= lowest;
|editorn= (and aliases) highest and |veditors= lowest (support for |editors= withdrawn)

When looking for |authorn= / |editorn= parameters, test |xxxxor1= and |xxxxor2= (and all of their aliases); stops after the second
test which mimicks the test used in extract_names() when looking for a hole in the author name list.  There may be a better
way to do this, I just haven't discovered what that way is.

Emits an error message when more than one xxxxor name source is provided.

In this function, vxxxxors = vauthors or veditors; xxxxors = authors as appropriate.

]]

local function select_author_editor_source (vxxxxors, xxxxors, args, list_name)
	local lastfirst = false;
	if utilities.select_one ( args, cfg.aliases[list_name .. '-Last'], 'none', 1 ) or		-- do this twice in case we have a |first1= without a |last1=; this ...
		utilities.select_one ( args, cfg.aliases[list_name .. '-First'], 'none', 1 ) or		-- ... also catches the case where |first= is used with |vauthors=
		utilities.select_one ( args, cfg.aliases[list_name .. '-Last'], 'none', 2 ) or
		utilities.select_one ( args, cfg.aliases[list_name .. '-First'], 'none', 2 ) then
			lastfirst = true;
	end

	if (utilities.is_set (vxxxxors) and true == lastfirst) or					-- these are the three error conditions
		(utilities.is_set (vxxxxors) and utilities.is_set (xxxxors)) or
		(true == lastfirst and utilities.is_set (xxxxors)) then
			local err_name;
			if 'AuthorList' == list_name then									-- figure out which name should be used in error message
				err_name = 'author';
			else
				err_name = 'editor';
			end
			table.insert( z.message_tail, { utilities.set_message ( 'err_redundant_parameters',
				{err_name .. '-name-list parameters'}, true ) } );				-- add error message
	end

	if true == lastfirst then return 1 end;										-- return a number indicating which author name source to use
	if utilities.is_set (vxxxxors) then return 2 end;
	if utilities.is_set (xxxxors) then return 3 end;
	return 1;																	-- no authors so return 1; this allows missing author name test to run in case there is a first without last 
end


--[[--------------------------< I S _ V A L I D _ P A R A M E T E R _ V A L U E >------------------------------

This function is used to validate a parameter's assigned value for those parameters that have only a limited number
of allowable values (yes, y, true, live, dead, etc.).  When the parameter value has not been assigned a value (missing
or empty in the source template) the function returns the value specified by ret_val.  If the parameter value is one
of the list of allowed values returns the translated value; else, emits an error message and returns the value
specified by ret_val.

]]

local function is_valid_parameter_value (value, name, possible, ret_val)
	if not utilities.is_set (value) then
		return ret_val;															-- an empty parameter is ok
	elseif utilities.in_array (value, possible) then
		return cfg.keywords_xlate[value];										-- return translation of parameter keyword
	else
		table.insert( z.message_tail, { utilities.set_message ( 'err_invalid_param_val', {name, value}, true ) } );	-- not an allowed value so add error message
		return ret_val;
	end
end


--[[--------------------------< T E R M I N A T E _ N A M E _ L I S T >----------------------------------------

This function terminates a name list (author, contributor, editor) with a separator character (sepc) and a space
when the last character is not a sepc character or when the last three characters are not sepc followed by two
closing square brackets (close of a wikilink).  When either of these is true, the name_list is terminated with a
single space character.

]]

local function terminate_name_list (name_list, sepc)
	if (string.sub (name_list, -3, -1) == sepc .. '. ') then					-- if already properly terminated
		return name_list;														-- just return the name list
	elseif (string.sub (name_list, -1, -1) == sepc) or (string.sub (name_list, -3, -1) == sepc .. ']]') then	-- if last name in list ends with sepc char
		return name_list .. " ";												-- don't add another
	else
		return name_list .. sepc .. ' ';										-- otherwise terminate the name list
	end
end


--[[-------------------------< F O R M A T _ V O L U M E _ I S S U E >----------------------------------------

returns the concatenation of the formatted volume and issue parameters as a single string; or formatted volume
or formatted issue, or an empty string if neither are set.

]]
	
local function format_volume_issue (volume, issue, cite_class, origin, sepc, lower)
	if not utilities.is_set (volume) and not utilities.is_set (issue) then
		return '';
	end
	
	if 'magazine' == cite_class or (utilities.in_array (cite_class, {'citation', 'map'}) and 'magazine' == origin) then
		if utilities.is_set (volume) and utilities.is_set (issue) then
			return wrap_msg ('vol-no', {sepc, hyphen_to_dash (volume), issue}, lower);
		elseif utilities.is_set (volume) then
			return wrap_msg ('vol', {sepc, hyphen_to_dash (volume)}, lower);
		else
			return wrap_msg ('issue', {sepc, issue}, lower);
		end
	end

	if 'podcast' == cite_class and utilities.is_set (issue) then
		return wrap_msg ('issue', {sepc, issue}, lower);
	end

	local vol = '';																-- here for all cites except magazine
		
	if utilities.is_set (volume) then
		if volume:match ('^[MDCLXVI]+$') or volume:match ('^%d+$') then			-- volume value is all digits or all uppercase Roman numerals
			vol = utilities.substitute (cfg.presentation['vol-bold'], {sepc, volume});	-- render in bold face
		elseif (4 < mw.ustring.len(volume)) then								-- not all digits or Roman numerals and longer than 4 characters
			vol = utilities.substitute (cfg.messages['j-vol'], {sepc, hyphen_to_dash (volume)});	-- not bold
			utilities.add_prop_cat ('long_vol');
		else																	-- four or less characters
			vol = utilities.substitute (cfg.presentation['vol-bold'], {sepc, hyphen_to_dash (volume)});	-- bold
		end
	end
	if utilities.is_set (issue) then
		return vol .. utilities.substitute (cfg.messages['j-issue'], issue);
	end
	return vol;
end


--[[-------------------------< F O R M A T _ P A G E S _ S H E E T S >-----------------------------------------

adds static text to one of |page(s)= or |sheet(s)= values and returns it with all of the others set to empty strings.
The return order is:
	page, pages, sheet, sheets

Singular has priority over plural when both are provided.

]]

local function format_pages_sheets (page, pages, sheet, sheets, cite_class, origin, sepc, nopp, lower)
	if 'map' == cite_class then													-- only cite map supports sheet(s) as in-source locators
		if utilities.is_set (sheet) then
			if 'journal' == origin then
				return '', '', wrap_msg ('j-sheet', sheet, lower), '';
			else
				return '', '', wrap_msg ('sheet', {sepc, sheet}, lower), '';
			end
		elseif utilities.is_set (sheets) then
			if 'journal' == origin then
				return '', '', '', wrap_msg ('j-sheets', sheets, lower);
			else
				return '', '', '', wrap_msg ('sheets', {sepc, sheets}, lower);
			end
		end
	end

	local is_journal = 'journal' == cite_class or (utilities.in_array (cite_class, {'citation', 'map', 'interview'}) and 'journal' == origin);
	
	if utilities.is_set (page) then
		if is_journal then
			return utilities.substitute (cfg.messages['j-page(s)'], page), '', '', '';
		elseif not nopp then
			return utilities.substitute (cfg.messages['p-prefix'], {sepc, page}), '', '', '';
		else
			return utilities.substitute (cfg.messages['nopp'], {sepc, page}), '', '', '';
		end
	elseif utilities.is_set (pages) then
		if is_journal then
			return utilities.substitute (cfg.messages['j-page(s)'], pages), '', '', '';
		elseif tonumber(pages) ~= nil and not nopp then							-- if pages is only digits, assume a single page number
			return '', utilities.substitute (cfg.messages['p-prefix'], {sepc, pages}), '', '';
		elseif not nopp then
			return '', utilities.substitute (cfg.messages['pp-prefix'], {sepc, pages}), '', '';
		else
			return '', utilities.substitute (cfg.messages['nopp'], {sepc, pages}), '', '';
		end
	end
	
	return '', '', '', '';														-- return empty strings
end


--[[--------------------------< I N S O U R C E _ L O C _ G E T >----------------------------------------------

returns one of the in-source locators: page, pages, or at. 

If any of these are interwiki links to Wikisource, returns the label portion of the interwiki-link as plain text
for use in COinS.  This COinS thing is done because here we convert an interwiki-link to an external link and
add an icon span around that; get_coins_pages() doesn't know about the span.  TODO: should it?  

TODO: add support for sheet and sheets?; streamline;

TODO: make it so that this function returns only one of the three as the single in-source (the return value assigned
to a new name)?

]]

local function insource_loc_get (page, page_orig, pages, pages_orig, at)
	local ws_url, ws_label, coins_pages, L;										-- for Wikisource interwiki-links; TODO: this corrupts page metadata (span remains in place after cleanup; fix there?)

	if utilities.is_set (page) then
		if utilities.is_set (pages) or utilities.is_set (at) then
			pages = '';															-- unset the others
			at = '';
		end
		extra_text_in_page_check (page, page_orig);								-- emit error message when |page= value begins with what looks like p., pp., etc.

		ws_url, ws_label, L = wikisource_url_make (page);						-- make ws URL from |page= interwiki link; link portion L becomes tooltip label
		if ws_url then
			page = external_link (ws_url, ws_label .. '&nbsp;', 'ws link in page');	-- space char after label to move icon away from in-source text; TODO: a better way to do this?
			page = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, page});
			coins_pages = ws_label;
		end
	elseif utilities.is_set (pages) then
		if utilities.is_set (at) then
			at = '';															-- unset
		end
		extra_text_in_page_check (pages, pages_orig);							-- emit error message when |page= value begins with what looks like p., pp., etc.

		ws_url, ws_label, L = wikisource_url_make (pages);						-- make ws URL from |pages= interwiki link; link portion L becomes tooltip label
		if ws_url then
			pages = external_link (ws_url, ws_label .. '&nbsp;', 'ws link in pages');	-- space char after label to move icon away from in-source text; TODO: a better way to do this?
			pages = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, pages});
			coins_pages = ws_label;
		end
	elseif utilities.is_set (at) then
		ws_url, ws_label, L = wikisource_url_make (at);							-- make ws URL from |at= interwiki link; link portion L becomes tooltip label
		if ws_url then
			at = external_link (ws_url, ws_label .. '&nbsp;', 'ws link in at');	-- space char after label to move icon away from in-source text; TODO: a better way to do this?
			at = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, at});
			coins_pages = ws_label;
		end
	end
	
	return page, pages, at, coins_pages;
end

--[[--------------------------< I S _ U N I Q U E _ A R C H I V E _ U R L >------------------------------------

add error message when |archive-url= value is same as |url= or chapter-url= (or alias...) value

]]

local function is_unique_archive_url (archive, url, c_url, source, date)
	if utilities.is_set (archive) then
		if archive == url or archive == c_url then
			table.insert (z.message_tail, {utilities.set_message ('err_bad_url', {utilities.wrap_style ('parameter', source)}, true)});	-- add error message
			return '', '';														-- unset |archive-url= and |archive-date= because same as |url= or |chapter-url=
		end
	end

	return archive, date;
end


--[=[-------------------------< A R C H I V E _ U R L _ C H E C K >--------------------------------------------

Check archive.org URLs to make sure they at least look like they are pointing at valid archives and not to the 
save snapshot URL or to calendar pages.  When the archive URL is 'https://web.archive.org/save/' (or http://...)
archive.org saves a snapshot of the target page in the URL.  That is something that Wikipedia should not allow
unwitting readers to do.

When the archive.org URL does not have a complete timestamp, archive.org chooses a snapshot according to its own
algorithm or provides a calendar 'search' result.  [[WP:ELNO]] discourages links to search results.

This function looks at the value assigned to |archive-url= and returns empty strings for |archive-url= and
|archive-date= and an error message when:
	|archive-url= holds an archive.org save command URL
	|archive-url= is an archive.org URL that does not have a complete timestamp (YYYYMMDDhhmmss 14 digits) in the
		correct place
otherwise returns |archive-url= and |archive-date=

There are two mostly compatible archive.org URLs:
	//web.archive.org/<timestamp>...		-- the old form
	//web.archive.org/web/<timestamp>...	-- the new form

The old form does not support or map to the new form when it contains a display flag.  There are four identified flags
('id_', 'js_', 'cs_', 'im_') but since archive.org ignores others following the same form (two letters and an underscore)
we don't check for these specific flags but we do check the form.

This function supports a preview mode.  When the article is rendered in preview mode, this function may return a modified
archive URL:
	for save command errors, return undated wildcard (/*/)
	for timestamp errors when the timestamp has a wildcard, return the URL unmodified
	for timestamp errors when the timestamp does not have a wildcard, return with timestamp limited to six digits plus wildcard (/yyyymm*/)

]=]

local function archive_url_check (url, date)
	local err_msg = '';															-- start with the error message empty
	local path, timestamp, flag;												-- portions of the archive.org URL
	
	if (not url:match('//web%.archive%.org/')) and (not url:match('//liveweb%.archive%.org/')) then		-- also deprecated liveweb Wayback machine URL
		return url, date;														-- not an archive.org archive, return ArchiveURL and ArchiveDate
	end

	if url:match('//web%.archive%.org/save/') then								-- if a save command URL, we don't want to allow saving of the target page 
		err_msg = cfg.err_msg_supl.save;
		url = url:gsub ('(//web%.archive%.org)/save/', '%1/*/', 1);				-- for preview mode: modify ArchiveURL
	elseif url:match('//liveweb%.archive%.org/') then
		err_msg = cfg.err_msg_supl.liveweb;
	else
		path, timestamp, flag = url:match('//web%.archive%.org/([^%d]*)(%d+)([^/]*)/');	-- split out some of the URL parts for evaluation
		
		if not utilities.is_set (timestamp) or 14 ~= timestamp:len() then		-- path and flag optional, must have 14-digit timestamp here
			err_msg = cfg.err_msg_supl.timestamp;
			if '*' ~= flag then
				url=url:gsub ('(//web%.archive%.org/[^%d]*%d?%d?%d?%d?%d?%d?)[^/]*', '%1*', 1)	-- for preview, modify ts to be yearmo* max (0-6 digits plus splat)
			end
		elseif utilities.is_set (path) and 'web/' ~= path then					-- older archive URLs do not have the extra 'web/' path element
			err_msg = cfg.err_msg_supl.path;
		elseif utilities.is_set (flag) and not utilities.is_set (path) then		-- flag not allowed with the old form URL (without the 'web/' path element)
			err_msg = cfg.err_msg_supl.flag;
		elseif utilities.is_set (flag) and not flag:match ('%a%a_') then		-- flag if present must be two alpha characters and underscore (requires 'web/' path element)
			err_msg = cfg.err_msg_supl.flag;
		else
			return url, date;													-- return ArchiveURL and ArchiveDate
		end
	end
																				-- if here, something not right so
	table.insert( z.message_tail, { utilities.set_message ( 'err_archive_url', {err_msg}, true ) } );	-- add error message and
	if utilities.is_set (Frame:preprocess('{{REVISIONID}}')) then
		return '', '';															-- return empty strings for ArchiveURL and ArchiveDate
	else
		return url, date;														-- preview mode so return ArchiveURL and ArchiveDate
	end
end


--[[--------------------------< P L A C E _ C H E C K >--------------------------------------------------------

check |place=, |publication-place=, |location= to see if these params include digits.  This function added because
many editors misuse location to specify the in-source location (|page(s)= and |at= are supposed to do that)

returns the original parameter value without modification; added maint cat when parameter value contains digits

]]

local function place_check (param_val)
	if not utilities.is_set (param_val) then									-- parameter empty or omitted
		return param_val;														-- return that empty state
	end
	
	if mw.ustring.find (param_val, '%d') then									-- not empty, are there digits in the parameter value
		utilities.set_message ('maint_location');								-- yep, add maint cat
	end
	
	return param_val;															-- and done
end


--[[--------------------------< I S _ G E N E R I C _ T I T L E >----------------------------------------------

compares |title= value against list of known generic title patterns.  Returns true when pattern matches; nil else

the k/v pairs in 'generic_titles' each contain two tables, one for English and one for another 'local' language
Each of those tables contain another table that holds the string or pattern (whole title or title fragment) in
index [1].  index [2] is a Boolean that tells string.find() or mw.ustring.find() to do plain-text search (true)
or a pattern search (false).  The intent of all this complexity is to make these searches as fast as possible so
that we don't run out of processing time on very large articles.

]]

local function is_generic_title (title)
	title = mw.ustring.lower(title);											-- switch title to lower case
	for _, generic_title in ipairs (cfg.special_case_translation['generic_titles']) do 	-- spin through the list of known generic title fragments
		if title:find (generic_title['en'][1], 1, generic_title['en'][2]) then
			return true;														-- found English generic title so done
		elseif generic_title['local'] then										-- to keep work load down, generic_title['local'] should be nil except when there is a local version of the generic title
			if mw.ustring.find (title, generic_title['local'][1], 1, generic_title['local'][2]) then	-- mw.ustring() because might not be Latin script
				return true;													-- found local generic title so done
			end
		end
	end
end


--[[--------------------------< I S _ A R C H I V E D _ C O P Y >----------------------------------------------

compares |title= to 'Archived copy' (placeholder added by bots that can't find proper title); if matches, return true; nil else

]]

local function is_archived_copy (title)
	title = mw.ustring.lower(title);											-- switch title to lower case
	if title:find (cfg.special_case_translation.archived_copy.en) then			-- if title is 'Archived copy'
		return true;
	elseif cfg.special_case_translation.archived_copy['local'] then
		if mw.ustring.find (title, cfg.special_case_translation.archived_copy['local']) then	-- mw.ustring() because might not be Latin script
			return true;
		end
	end
end


--[[--------------------------< C I T A T I O N 0 >------------------------------------------------------------

This is the main function doing the majority of the citation formatting.

]]

local function citation0( config, args )
	--[[ 
	Load Input Parameters
	The argument_wrapper facilitates the mapping of multiple aliases to single internal variable.
	]]
	local A = argument_wrapper ( args );
	local i 

	-- Pick out the relevant fields from the arguments.  Different citation templates
	-- define different field names for the same underlying things.	

	local author_etal;
	local a	= {};																-- authors list from |lastn= / |firstn= pairs or |vauthors=
	local Authors;
	local NameListStyle = is_valid_parameter_value (A['NameListStyle'], A:ORIGIN('NameListStyle'), cfg.keywords_lists['name-list-style'], '');
	local Collaboration = A['Collaboration'];

	do																			-- to limit scope of selected
		local selected = select_author_editor_source (A['Vauthors'], A['Authors'], args, 'AuthorList');
		if 1 == selected then
			a, author_etal = extract_names (args, 'AuthorList');				-- fetch author list from |authorn= / |lastn= / |firstn=, |author-linkn=, and |author-maskn=
		elseif 2 == selected then
			NameListStyle = 'vanc';												-- override whatever |name-list-style= might be
			a, author_etal = parse_vauthors_veditors (args, args.vauthors, 'AuthorList');	-- fetch author list from |vauthors=, |author-linkn=, and |author-maskn=
		elseif 3 == selected then
			Authors = A['Authors'];												-- use content of |authors=
			if 'authors' == A:ORIGIN('Authors') then							-- but add a maint cat if the parameter is |authors=
				utilities.set_message ('maint_authors');						-- because use of this parameter is discouraged; what to do about the aliases is a TODO:
			end
		end
		if utilities.is_set (Collaboration) then
			author_etal = true;													-- so that |display-authors=etal not required
		end
	end

	local editor_etal;
	local e	= {};																-- editors list from |editor-lastn= / |editor-firstn= pairs or |veditors=

	do																			-- to limit scope of selected
		local selected = select_author_editor_source (A['Veditors'], nil, args, 'EditorList');	-- support for |editors= withdrawn
		if 1 == selected then
			e, editor_etal = extract_names (args, 'EditorList');				-- fetch editor list from |editorn= / |editor-lastn= / |editor-firstn=, |editor-linkn=, and |editor-maskn=
		elseif 2 == selected then
			NameListStyle = 'vanc';												-- override whatever |name-list-style= might be
			e, editor_etal = parse_vauthors_veditors (args, args.veditors, 'EditorList');	-- fetch editor list from |veditors=, |editor-linkn=, and |editor-maskn=
		end
	end
							
	local Chapter = A['Chapter'];												-- done here so that we have access to |contribution= from |chapter= aliases
	local Chapter_origin = A:ORIGIN ('Chapter');
	local Contribution;															-- because contribution is required for contributor(s)
		if 'contribution' == Chapter_origin then
			Contribution = Chapter;												-- get the name of the contribution
		end
	local c = {};																-- contributors list from |contributor-lastn= / contributor-firstn= pairs
	
	if utilities.in_array (config.CitationClass, {"book", "citation"}) and not utilities.is_set (A['Periodical']) then	-- |contributor= and |contribution= only supported in book cites
		c = extract_names (args, 'ContributorList');							-- fetch contributor list from |contributorn= / |contributor-lastn=, -firstn=, -linkn=, -maskn=
		
		if 0 < #c then
			if not utilities.is_set (Contribution) then							-- |contributor= requires |contribution=
				table.insert( z.message_tail, { utilities.set_message ( 'err_contributor_missing_required_param', 'contribution')});	-- add missing contribution error message
				c = {};															-- blank the contributors' table; it is used as a flag later
			end
			if 0 == #a then														-- |contributor= requires |author=
				table.insert( z.message_tail, { utilities.set_message ( 'err_contributor_missing_required_param', 'author')});	-- add missing author error message
				c = {};															-- blank the contributors' table; it is used as a flag later
			end
		end
	else																		-- if not a book cite
		if utilities.select_one (args, cfg.aliases['ContributorList-Last'], 'err_redundant_parameters', 1 ) then	-- are there contributor name list parameters?
			table.insert( z.message_tail, { utilities.set_message ( 'err_contributor_ignored')});	-- add contributor ignored error message
		end
		Contribution = nil;														-- unset
	end

	local Title = A['Title'];
	local TitleLink = A['TitleLink'];

	local auto_select = ''; -- default is auto
	local accept_link;
	TitleLink, accept_link = utilities.has_accept_as_written(TitleLink, true);	-- test for accept-this-as-written markup
	if (not accept_link) and utilities.in_array (TitleLink, {'none', 'pmc', 'doi'}) then -- check for special keywords
		auto_select = TitleLink;												-- remember selection for later
		TitleLink = '';															-- treat as if |title-link= would have been empty
	end

	TitleLink = link_title_ok (TitleLink, A:ORIGIN ('TitleLink'), Title, 'title');	-- check for wiki-markup in |title-link= or wiki-markup in |title= when |title-link= is set

	local Section = '';															-- {{cite map}} only; preset to empty string for concatenation if not used
	if 'map' == config.CitationClass and 'section' == Chapter_origin then
		Section = A['Chapter'];													-- get |section= from |chapter= alias list; |chapter= and the other aliases not supported in {{cite map}}
		Chapter = '';															-- unset for now; will be reset later from |map= if present
	end

	local Periodical = A['Periodical'];
	local Periodical_origin = '';
	if utilities.is_set (Periodical) then
		Periodical_origin = A:ORIGIN('Periodical');								-- get the name of the periodical parameter
		local i;
		Periodical, i = utilities.strip_apostrophe_markup (Periodical);			-- strip apostrophe markup so that metadata isn't contaminated 
		if i then																-- non-zero when markup was stripped so emit an error message
			table.insert( z.message_tail, {utilities.set_message ('err_apostrophe_markup', {Periodical_origin}, true)});
		end
	end

	if 'mailinglist' == config.CitationClass then								-- special case for {{cite mailing list}}
		if utilities.is_set (Periodical) and utilities.is_set (A ['MailingList']) then	-- both set emit an error
			table.insert( z.message_tail, {utilities.set_message ('err_redundant_parameters', {utilities.wrap_style ('parameter', Periodical_origin) .. ' and ' .. utilities.wrap_style ('parameter', 'mailinglist')}, true )});
		end

		Periodical = A ['MailingList'];											-- error or no, set Periodical to |mailinglist= value because this template is {{cite mailing list}}
		Periodical_origin = A:ORIGIN('MailingList');
	end

	local ScriptPeriodical = A['ScriptPeriodical'];

	-- web and news not tested for now because of 
	-- Wikipedia:Administrators%27_noticeboard#Is_there_a_semi-automated_tool_that_could_fix_these_annoying_"Cite_Web"_errors?
	if not (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) then	-- 'periodical' templates require periodical parameter
	--	local p = {['journal'] = 'journal', ['magazine'] = 'magazine', ['news'] = 'newspaper', ['web'] = 'website'};	-- for error message
		local p = {['journal'] = 'journal', ['magazine'] = 'magazine'};			-- for error message
		if p[config.CitationClass]  then
			table.insert( z.message_tail, {utilities.set_message ('err_missing_periodical', {config.CitationClass, p[config.CitationClass]}, true)});
		end
	end
	
	local Volume;
	local ScriptPeriodical_origin = A:ORIGIN('ScriptPeriodical');
	if 'citation' == config.CitationClass then
		if utilities.is_set (Periodical) then
			if not utilities.in_array (Periodical_origin, {'website', 'mailinglist'}) then	-- {{citation}} does not render volume for these 'periodicals'
				Volume = A['Volume'];											-- but does for all other 'periodicals'
			end
		elseif utilities.is_set (ScriptPeriodical) then
			if 'script-website' ~= ScriptPeriodical_origin then					-- {{citation}} does not render volume for |script-website=
				Volume = A['Volume'];											-- but does for all other 'periodicals'
			end
		else
			Volume = A['Volume'];												-- and does for non-'periodical' cites
		end
	elseif utilities.in_array (config.CitationClass, cfg.templates_using_volume) then	-- render |volume= for cs1 according to the configuration settings
		Volume = A['Volume'];
	end	
	extra_text_in_vol_iss_check (Volume, A:ORIGIN ('Volume'), 'v');	

	local Issue;
	if 'citation' == config.CitationClass then
		if utilities.is_set (Periodical) and utilities.in_array (Periodical_origin, {'journal', 'magazine', 'newspaper', 'periodical', 'work'}) or	-- {{citation}} renders issue for these 'periodicals'
			utilities.is_set (ScriptPeriodical) and utilities.in_array (ScriptPeriodical_origin, {'script-journal', 'script-magazine', 'script-newspaper', 'script-periodical', 'script-work'}) then -- and these 'script-periodicals'
				Issue = hyphen_to_dash (A['Issue']);
		end
	elseif utilities.in_array (config.CitationClass, cfg.templates_using_issue) then	-- conference & map books do not support issue; {{citation}} listed here because included in settings table
		if not (utilities.in_array (config.CitationClass, {'conference', 'map', 'citation'}) and not (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical))) then
			Issue = hyphen_to_dash (A['Issue']);
		end
	end
	extra_text_in_vol_iss_check (Issue, A:ORIGIN ('Issue'), 'i');	

	local Page;
	local Pages;
	local At;
	if not utilities.in_array (config.CitationClass, cfg.templates_not_using_page) then
		Page = A['Page'];
		Pages = hyphen_to_dash (A['Pages']);	
		At = A['At'];
	end

	local Edition = A['Edition'];
	local PublicationPlace = place_check (A['PublicationPlace'], A:ORIGIN('PublicationPlace'));
	local Place = place_check (A['Place'], A:ORIGIN('Place'));
	
	local PublisherName = A['PublisherName'];
	local PublisherName_origin = A:ORIGIN('PublisherName');
	if utilities.is_set (PublisherName) then
		local i = 0;
		PublisherName, i = utilities.strip_apostrophe_markup (PublisherName);	-- strip apostrophe markup so that metadata isn't contaminated; publisher is never italicized
		if i then																-- non-zero when markup was stripped so emit an error message
			table.insert( z.message_tail, {utilities.set_message ('err_apostrophe_markup', {PublisherName_origin}, true)});
		end
	end

	local Newsgroup = A['Newsgroup'];											-- TODO: strip apostrophe markup?
	local Newsgroup_origin = A:ORIGIN('Newsgroup');	

	if 'newsgroup' == config.CitationClass then
		if utilities.is_set (PublisherName) then								-- general use parameter |publisher= not allowed in cite newsgroup
			local error_text, error_state = utilities.set_message ('err_parameter_ignored', {PublisherName_origin}, true);
			if utilities.is_set (error_text) then
				table.insert( z.message_tail, {error_text, error_state} );
			end				
		end

		PublisherName = nil;													-- ensure that this parameter is unset for the time being; will be used again after COinS
	end

	local URL = A['URL']
	local UrlAccess = is_valid_parameter_value (A['UrlAccess'], A:ORIGIN('UrlAccess'), cfg.keywords_lists['url-access'], nil);
	
	if not utilities.is_set (URL) and utilities.is_set (UrlAccess) then
		UrlAccess = nil;
		table.insert( z.message_tail, { utilities.set_message ( 'err_param_access_requires_param', {'url'}, true ) } );
	end
	
	local ChapterURL = A['ChapterURL'];
	local ChapterUrlAccess = is_valid_parameter_value (A['ChapterUrlAccess'], A:ORIGIN('ChapterUrlAccess'), cfg.keywords_lists['url-access'], nil);
	if not utilities.is_set (ChapterURL) and utilities.is_set (ChapterUrlAccess) then
		ChapterUrlAccess = nil;
		table.insert( z.message_tail, { utilities.set_message ( 'err_param_access_requires_param', {A:ORIGIN('ChapterUrlAccess'):gsub ('%-access', '')}, true ) } );
	end

	local MapUrlAccess = is_valid_parameter_value (A['MapUrlAccess'], A:ORIGIN('MapUrlAccess'), cfg.keywords_lists['url-access'], nil);
	if not utilities.is_set (A['MapURL']) and utilities.is_set (MapUrlAccess) then
		MapUrlAccess = nil;
		table.insert( z.message_tail, { utilities.set_message ( 'err_param_access_requires_param', {'map-url'}, true ) } );
	end

	local this_page = mw.title.getCurrentTitle();								-- also used for COinS and for language
	local no_tracking_cats = is_valid_parameter_value (A['NoTracking'], A:ORIGIN('NoTracking'), cfg.keywords_lists['yes_true_y'], nil);

	-- check this page to see if it is in one of the namespaces that cs1 is not supposed to add to the error categories
	if not utilities.is_set (no_tracking_cats) then								-- ignore if we are already not going to categorize this page
		if utilities.in_array (this_page.nsText, cfg.uncategorized_namespaces) then
			no_tracking_cats = "true";											-- set no_tracking_cats
		end
		for _, v in ipairs (cfg.uncategorized_subpages) do						-- cycle through page name patterns
			if this_page.text:match (v) then									-- test page name against each pattern
				no_tracking_cats = "true";										-- set no_tracking_cats
				break;															-- bail out if one is found
			end
		end
	end
																				-- check for extra |page=, |pages= or |at= parameters. (also sheet and sheets while we're at it)
	utilities.select_one (args, {'page', 'p', 'pp', 'pages', 'at', 'sheet', 'sheets'}, 'err_redundant_parameters');	-- this is a dummy call simply to get the error message and category

	local coins_pages;
	
	Page, Pages, At, coins_pages = insource_loc_get (Page, A:ORIGIN('Page'), Pages, A:ORIGIN('Pages'), At);

	local NoPP = is_valid_parameter_value (A['NoPP'], A:ORIGIN('NoPP'), cfg.keywords_lists['yes_true_y'], nil);

	if utilities.is_set (PublicationPlace) and utilities.is_set (Place) then	-- both |publication-place= and |place= (|location=) allowed if different
		utilities.add_prop_cat ('location test');								-- add property cat to evaluate how often PublicationPlace and Place are used together
		if PublicationPlace == Place then
			Place = '';															-- unset; don't need both if they are the same
		end
	elseif not utilities.is_set (PublicationPlace) and utilities.is_set (Place) then	-- when only |place= (|location=) is set ...
		PublicationPlace = Place;												-- promote |place= (|location=) to |publication-place
	end

	if PublicationPlace == Place then Place = ''; end							-- don't need both if they are the same
	
	local URL_origin = A:ORIGIN('URL');											-- get name of parameter that holds URL
	local ChapterURL_origin = A:ORIGIN('ChapterURL');							-- get name of parameter that holds ChapterURL
	local ScriptChapter = A['ScriptChapter'];
	local ScriptChapter_origin = A:ORIGIN ('ScriptChapter');
	local Format = A['Format'];
	local ChapterFormat = A['ChapterFormat'];
	local TransChapter = A['TransChapter'];
	local TransChapter_origin = A:ORIGIN ('TransChapter');
	local TransTitle = A['TransTitle'];
	local ScriptTitle = A['ScriptTitle'];
	
	--[[
	Parameter remapping for cite encyclopedia:
	When the citation has these parameters:
		|encyclopedia= and |title= then map |title= to |article= and |encyclopedia= to |title=
		|encyclopedia= and |article= then map |encyclopedia= to |title=

		|trans-title= maps to |trans-chapter= when |title= is re-mapped
		|url= maps to |chapter-url= when |title= is remapped
	
	All other combinations of |encyclopedia=, |title=, and |article= are not modified
	
	]]

	local Encyclopedia = A['Encyclopedia'];										-- used as a flag by this module and by ~/COinS

	if utilities.is_set (Encyclopedia) then										-- emit error message when Encyclopedia set but template is other than {{cite encyclopedia}} or {{citation}}
		if 'encyclopaedia' ~= config.CitationClass and 'citation' ~= config.CitationClass then
			table.insert (z.message_tail, {utilities.set_message ('err_parameter_ignored', {A:ORIGIN ('Encyclopedia')}, true)});
			Encyclopedia = nil;													-- unset because not supported by this template
		end
	end

	if ('encyclopaedia' == config.CitationClass) or ('citation' == config.CitationClass and utilities.is_set (Encyclopedia)) then
		if utilities.is_set (Periodical) and utilities.is_set (Encyclopedia) then	-- when both set emit an error
			table.insert (z.message_tail, {utilities.set_message ('err_redundant_parameters', {utilities.wrap_style ('parameter', A:ORIGIN ('Encyclopedia')) .. ' and ' .. utilities.wrap_style ('parameter', Periodical_origin)}, true )});
		end

		if utilities.is_set (Encyclopedia) then
			Periodical = Encyclopedia;											-- error or no, set Periodical to Encyclopedia; allow periodical without encyclopedia
			Periodical_origin = A:ORIGIN ('Encyclopedia');
		end

		if utilities.is_set (Periodical) then									-- Periodical is set when |encyclopedia= is set
			if utilities.is_set (Title) or utilities.is_set (ScriptTitle) then
				if not utilities.is_set (Chapter) then
					Chapter = Title;											-- |encyclopedia= and |title= are set so map |title= to |article= and |encyclopedia= to |title=
					ScriptChapter = ScriptTitle;
					ScriptChapter_origin = A:ORIGIN('ScriptTitle')
					TransChapter = TransTitle;
					ChapterURL = URL;
					ChapterURL_origin = URL_origin;

					ChapterUrlAccess = UrlAccess;

					if not utilities.is_set (ChapterURL) and utilities.is_set (TitleLink) then
						Chapter = utilities.make_wikilink (TitleLink, Chapter);
					end
					Title = Periodical;
					ChapterFormat = Format;
					Periodical = '';											-- redundant so unset
					TransTitle = '';
					URL = '';
					Format = '';
					TitleLink = '';
					ScriptTitle = '';
				end
			elseif utilities.is_set (Chapter) then								-- |title= not set
				Title = Periodical;												-- |encyclopedia= set and |article= set so map |encyclopedia= to |title=
				Periodical = '';												-- redundant so unset
			end
		end
	end

	-- special case for cite techreport.
	local ID = A['ID'];
	if (config.CitationClass == "techreport") then								-- special case for cite techreport
		if utilities.is_set (A['Number']) then									-- cite techreport uses 'number', which other citations alias to 'issue'
			if not utilities.is_set (ID) then									-- can we use ID for the "number"?
				ID = A['Number'];												-- yes, use it
			else																-- ID has a value so emit error message
				table.insert( z.message_tail, { utilities.set_message ('err_redundant_parameters', {utilities.wrap_style ('parameter', 'id') .. ' and ' .. utilities.wrap_style ('parameter', 'number')}, true )});
			end
		end	
	end

	-- Account for the oddity that is {{cite conference}}, before generation of COinS data.
	local ChapterLink -- = A['ChapterLink'];									-- deprecated as a parameter but still used internally by cite episode
	local Conference = A['Conference'];
	local BookTitle = A['BookTitle'];
	local TransTitle_origin = A:ORIGIN ('TransTitle');
	if 'conference' == config.CitationClass then
		if utilities.is_set (BookTitle) then
			Chapter = Title;
			Chapter_origin = 'title';
	--		ChapterLink = TitleLink;											-- |chapter-link= is deprecated
			ChapterURL = URL;
			ChapterUrlAccess = UrlAccess;
			ChapterURL_origin = URL_origin;
			URL_origin = '';
			ChapterFormat = Format;
			TransChapter = TransTitle;
			TransChapter_origin = TransTitle_origin;
			Title = BookTitle;
			Format = '';
	--		TitleLink = '';
			TransTitle = '';
			URL = '';
		end
	elseif 'speech' ~= config.CitationClass then
		Conference = '';														-- not cite conference or cite speech so make sure this is empty string
	end
	
	-- CS1/2 mode
	local Mode = is_valid_parameter_value (A['Mode'], A:ORIGIN('Mode'), cfg.keywords_lists['mode'], '');
	-- separator character and postscript
	local sepc, PostScript = set_style (Mode:lower(), A['PostScript'], config.CitationClass);
	-- controls capitalization of certain static text
	local use_lowercase = ( sepc == ',' );
	
	-- cite map oddities
	local Cartography = "";
	local Scale = "";
	local Sheet = A['Sheet'] or '';
	local Sheets = A['Sheets'] or '';
	if config.CitationClass == "map" then
		if utilities.is_set (Chapter) then
			table.insert( z.message_tail, { utilities.set_message ( 'err_redundant_parameters', {utilities.wrap_style ('parameter', 'map') .. ' and ' .. utilities.wrap_style ('parameter', Chapter_origin)}, true ) } );	-- add error message
		end
		Chapter = A['Map'];
		Chapter_origin = A:ORIGIN('Map');
		ChapterURL = A['MapURL'];
		ChapterURL_origin = A:ORIGIN('MapURL');
		TransChapter = A['TransMap'];
		ScriptChapter = A['ScriptMap']
		ScriptChapter_origin = A:ORIGIN('ScriptMap')

		ChapterUrlAccess = MapUrlAccess;
		ChapterFormat = A['MapFormat'];

		Cartography = A['Cartography'];
		if utilities.is_set ( Cartography ) then
			Cartography = sepc .. " " .. wrap_msg ('cartography', Cartography, use_lowercase);
		end		
		Scale = A['Scale'];
		if utilities.is_set ( Scale ) then
			Scale = sepc .. " " .. Scale;
		end
	end

	-- Account for the oddities that are {{cite episode}} and {{cite serial}}, before generation of COinS data.
	local Series = A['Series'];
	if 'episode' == config.CitationClass or 'serial' == config.CitationClass then
		local SeriesLink = A['SeriesLink'];

		SeriesLink = link_title_ok (SeriesLink, A:ORIGIN ('SeriesLink'), Series, 'series');	-- check for wiki-markup in |series-link= or wiki-markup in |series= when |series-link= is set

		local Network = A['Network'];
		local Station = A['Station'];
		local s, n = {}, {};
																				-- do common parameters first
		if utilities.is_set (Network) then table.insert(n, Network); end
		if utilities.is_set (Station) then table.insert(n, Station); end
		ID = table.concat(n, sepc .. ' ');
		
		if 'episode' == config.CitationClass then								-- handle the oddities that are strictly {{cite episode}}
			local Season = A['Season'];
			local SeriesNumber = A['SeriesNumber'];

			if utilities.is_set (Season) and utilities.is_set (SeriesNumber) then	-- these are mutually exclusive so if both are set
				table.insert( z.message_tail, { utilities.set_message ( 'err_redundant_parameters', {utilities.wrap_style ('parameter', 'season') .. ' and ' .. utilities.wrap_style ('parameter', 'seriesno')}, true ) } );		-- add error message
				SeriesNumber = '';												-- unset; prefer |season= over |seriesno=
			end
																				-- assemble a table of parts concatenated later into Series
			if utilities.is_set (Season) then table.insert(s, wrap_msg ('season', Season, use_lowercase)); end
			if utilities.is_set (SeriesNumber) then table.insert(s, wrap_msg ('seriesnum', SeriesNumber, use_lowercase)); end
			if utilities.is_set (Issue) then table.insert(s, wrap_msg ('episode', Issue, use_lowercase)); end
			Issue = '';															-- unset because this is not a unique parameter
	
			Chapter = Title;													-- promote title parameters to chapter
			ScriptChapter = ScriptTitle;
			ScriptChapter_origin = A:ORIGIN('ScriptTitle');
			ChapterLink = TitleLink;											-- alias |episode-link=
			TransChapter = TransTitle;
			ChapterURL = URL;
			ChapterUrlAccess = UrlAccess;
			ChapterURL_origin = URL_origin;
			
			Title = Series;														-- promote series to title
			TitleLink = SeriesLink;
			Series = table.concat(s, sepc .. ' ');								-- this is concatenation of season, seriesno, episode number

			if utilities.is_set (ChapterLink) and not utilities.is_set (ChapterURL) then	-- link but not URL
				Chapter = utilities.make_wikilink (ChapterLink, Chapter);
			elseif utilities.is_set (ChapterLink) and utilities.is_set (ChapterURL) then	-- if both are set, URL links episode;
				Series = utilities.make_wikilink (ChapterLink, Series);
			end
			URL = '';															-- unset
			TransTitle = '';
			ScriptTitle = '';
			
		else																	-- now oddities that are cite serial
			Issue = '';															-- unset because this parameter no longer supported by the citation/core version of cite serial
			Chapter = A['Episode'];												-- TODO: make |episode= available to cite episode someday?
			if utilities.is_set (Series) and utilities.is_set (SeriesLink) then
				Series = utilities.make_wikilink (SeriesLink, Series);
			end
			Series = utilities.wrap_style ('italic-title', Series);				-- series is italicized
		end	
	end
	-- end of {{cite episode}} stuff

	-- handle type parameter for those CS1 citations that have default values
	local TitleType = A['TitleType'];
	local Degree = A['Degree'];
	if utilities.in_array (config.CitationClass, {"AV-media-notes", "interview", "mailinglist", "map", "podcast", "pressrelease", "report", "techreport", "thesis"}) then
		TitleType = set_titletype (config.CitationClass, TitleType);
		if utilities.is_set (Degree) and "Thesis" == TitleType then				-- special case for cite thesis
			TitleType = Degree .. ' ' .. cfg.title_types ['thesis']:lower();
		end
	end

	if utilities.is_set (TitleType) then										-- if type parameter is specified
		TitleType = utilities.substitute ( cfg.messages['type'], TitleType);	-- display it in parentheses
	-- TODO: Hack on TitleType to fix bunched parentheses problem
	end

	-- legacy: promote PublicationDate to Date if neither Date nor Year are set.
	local Date = A['Date'];
 	local Date_origin;															-- to hold the name of parameter promoted to Date; required for date error messaging
	local PublicationDate = A['PublicationDate'];
	local Year = A['Year'];

	if not utilities.is_set (Date) then
		Date = Year;															-- promote Year to Date
		Year = nil;																-- make nil so Year as empty string isn't used for CITEREF
		if not utilities.is_set (Date) and utilities.is_set (PublicationDate) then	-- use PublicationDate when |date= and |year= are not set
			Date = PublicationDate;												-- promote PublicationDate to Date
			PublicationDate = '';												-- unset, no longer needed
			Date_origin = A:ORIGIN('PublicationDate');							-- save the name of the promoted parameter
		else
			Date_origin = A:ORIGIN('Year');										-- save the name of the promoted parameter
		end
	else
		Date_origin = A:ORIGIN('Date');											-- not a promotion; name required for error messaging
	end

	if PublicationDate == Date then PublicationDate = ''; end					-- if PublicationDate is same as Date, don't display in rendered citation

	--[[
	Go test all of the date-holding parameters for valid MOS:DATE format and make sure that dates are real dates. This must be done before we do COinS because here is where
	we get the date used in the metadata.
	
	Date validation supporting code is in Module:Citation/CS1/Date_validation
	]]

	local DF = is_valid_parameter_value (A['DF'], A:ORIGIN('DF'), cfg.keywords_lists['df'], '');
	if not utilities.is_set (DF) then
		DF = cfg.global_df;														-- local |df= if present overrides global df set by {{use xxx date}} template
	end

	local ArchiveURL;
	local ArchiveDate;
	local ArchiveFormat = A['ArchiveFormat'];

	ArchiveURL, ArchiveDate = archive_url_check (A['ArchiveURL'], A['ArchiveDate'])
	ArchiveFormat = style_format (ArchiveFormat, ArchiveURL, 'archive-format', 'archive-url');
	
	ArchiveURL, ArchiveDate = is_unique_archive_url (ArchiveURL, URL, ChapterURL, A:ORIGIN('ArchiveURL'), ArchiveDate);		-- add error message when URL or ChapterURL == ArchiveURL

	
	local AccessDate = A['AccessDate'];
	local LayDate = A['LayDate'];
	local COinS_date = {};														-- holds date info extracted from |date= for the COinS metadata by Module:Date verification
	local DoiBroken = A['DoiBroken'];
	local Embargo = A['Embargo'];
	local anchor_year;															-- used in the CITEREF identifier
	do	-- create defined block to contain local variables error_message, date_parameters_list, mismatch
		local error_message = '';
																				-- AirDate has been promoted to Date so not necessary to check it
		local date_parameters_list = {
			['access-date'] = {val = AccessDate, name = A:ORIGIN ('AccessDate')},
			['archive-date'] = {val = ArchiveDate, name = A:ORIGIN ('ArchiveDate')},
			['date'] = {val = Date, name = Date_origin},
			['doi-broken-date'] = {val = DoiBroken, name = A:ORIGIN ('DoiBroken')},
			['pmc-embargo-date'] = {val = Embargo, name = A:ORIGIN ('Embargo')},
			['lay-date'] = {val = LayDate, name = A:ORIGIN ('LayDate')},
			['publication-date'] = {val = PublicationDate, name = A:ORIGIN ('PublicationDate')},
			['year'] = {val = Year, name = A:ORIGIN ('Year')},
			};

		local error_list = {};
		anchor_year, Embargo = validation.dates(date_parameters_list, COinS_date, error_list);

-- start temporary Julian / Gregorian calendar uncertainty categorization
		if COinS_date.inter_cal_cat then
			utilities.add_prop_cat ('jul_greg_uncertainty');
		end
-- end temporary Julian / Gregorian calendar uncertainty categorization

		if utilities.is_set (Year) and utilities.is_set (Date) then				-- both |date= and |year= not normally needed; 
			validation.year_date_check (Year, A:ORIGIN ('Year'), Date, A:ORIGIN ('Date'), error_list);
		end
		
		if 0 == #error_list then												-- error free dates only; 0 when error_list is empty
			local modified = false;												-- flag
			
			if validation.edtf_transform (date_parameters_list) then			-- edtf dates to MOS compliant format
				modified = true;
			end

			if utilities.is_set (DF) then										-- if we need to reformat dates
				modified = validation.reformat_dates (date_parameters_list, DF);	-- reformat to DF format, use long month names if appropriate
			end

			if true == validation.date_hyphen_to_dash (date_parameters_list) then	-- convert hyphens to dashes where appropriate
				modified = true;
				utilities.set_message ('maint_date_format');					-- hyphens were converted so add maint category
			end
			
	-- for those wikis that can and want to have English date names translated to the local language,
	-- uncomment the next three lines.  Not supported by en.wiki (for obvious reasons)
	-- set validation.date_name_xlate() second argument to true to translate English digits to local digits (will translate ymd dates)
	--		if validation.date_name_xlate (date_parameters_list, false) then
	--			modified = true;
	--		end

			if modified then													-- if the date_parameters_list values were modified
				AccessDate = date_parameters_list['access-date'].val;			-- overwrite date holding parameters with modified values
				ArchiveDate = date_parameters_list['archive-date'].val;
				Date = date_parameters_list['date'].val;
				DoiBroken = date_parameters_list['doi-broken-date'].val;
				LayDate = date_parameters_list['lay-date'].val;
				PublicationDate = date_parameters_list['publication-date'].val;
			end
		else
			table.insert (z.message_tail, {utilities.set_message ('err_bad_date', {utilities.make_sep_list (#error_list, error_list)}, true)});	-- add this error message
		end
	end	-- end of do

	local ID_list = {};															-- sequence table of rendered identifiers
	local ID_list_coins = {};													-- table of identifiers and their values from args; key is same as cfg.id_handlers's key
	local Class = A['Class'];													-- arxiv class identifier
	
	local ID_support = {
		{A['ASINTLD'], 'ASIN', 'err_asintld_missing_asin', A:ORIGIN ('ASINTLD')},				
		{DoiBroken, 'DOI', 'err_doibroken_missing_doi', A:ORIGIN ('DoiBroken')},
		{Embargo, 'PMC', 'err_embargo_missing_pmc', A:ORIGIN ('Embargo')},
		}

	ID_list, ID_list_coins = identifiers.identifier_lists_get (args, {DoiBroken = DoiBroken, ASINTLD = A['ASINTLD'], Embargo = Embargo, Class = Class}, ID_support);

	-- Account for the oddities that are {{cite arxiv}}, {{cite biorxiv}}, {{cite citeseerx}}, {{cite ssrn}}, before generation of COinS data.
	if utilities.in_array (config.CitationClass, whitelist.preprint_template_list) then
		if not utilities.is_set (ID_list_coins[config.CitationClass:upper()]) then 	-- |arxiv= or |eprint= required for cite arxiv; |biorxiv= & |citeseerx= required for their templates
			table.insert (z.message_tail, {utilities.set_message ('err_' .. config.CitationClass .. '_missing', {}, true)});	-- add error message
		end

		Periodical = ({['arxiv'] = 'arXiv', ['biorxiv'] = 'bioRxiv', ['citeseerx'] = 'CiteSeerX', ['ssrn'] = 'Social Science Research Network'})[config.CitationClass];
	end

	-- Link the title of the work if no |url= was provided, but we have a |pmc= or a |doi= with |doi-access=free

	if config.CitationClass == "journal" and not utilities.is_set (URL) and not utilities.is_set (TitleLink) and not utilities.in_array (cfg.keywords_xlate[Title], {'off', 'none'}) then -- TODO: remove 'none' once existing citations have been switched to 'off', so 'none' can be used as token for "no title" instead
		if 'none' ~= cfg.keywords_xlate[auto_select] then						-- if auto-linking not disabled
 	 		if identifiers.auto_link_urls[auto_select] then						-- manual selection
		 		URL = identifiers.auto_link_urls[auto_select];					-- set URL to be the same as identifier's external link
 				URL_origin = cfg.id_handlers[auto_select:upper()].parameters[1];	-- set URL_origin to parameter name for use in error message if citation is missing a |title=
			elseif identifiers.auto_link_urls['pmc'] then						-- auto-select PMC
				URL = identifiers.auto_link_urls['pmc'];						-- set URL to be the same as the PMC external link if not embargoed
				URL_origin = cfg.id_handlers['PMC'].parameters[1];				-- set URL_origin to parameter name for use in error message if citation is missing a |title=
			elseif identifiers.auto_link_urls['doi'] then						-- auto-select DOI
				URL = identifiers.auto_link_urls['doi'];
				URL_origin = cfg.id_handlers['DOI'].parameters[1];
			end
 	 	end

		if utilities.is_set (URL) and utilities.is_set (AccessDate) then		-- access date requires |url=; identifier-created URL is not |url=
			table.insert( z.message_tail, { utilities.set_message ( 'err_accessdate_missing_url', {}, true ) } );	-- add an error message
			AccessDate = '';													-- unset
		end
	end

	-- At this point fields may be nil if they weren't specified in the template use.  We can use that fact.
	-- Test if citation has no title
	if	not utilities.is_set (Title) and not utilities.is_set (TransTitle) and not utilities.is_set (ScriptTitle) then	-- has special case for cite episode
		table.insert( z.message_tail, { utilities.set_message ( 'err_citation_missing_title', {'episode' == config.CitationClass and 'series' or 'title'}, true ) } );
	end

	if utilities.in_array (cfg.keywords_xlate[Title], {'off', 'none'}) and
			utilities.in_array (config.CitationClass, {'journal', 'citation'}) and
			(utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and
			('journal' == Periodical_origin or 'script-journal' == ScriptPeriodical_origin) then	-- special case for journal cites
				Title = '';														-- set title to empty string
				utilities.set_message ('maint_untitled');						-- add maint cat
	end

	check_for_url ({															-- add error message when any of these parameters hold a URL
		['title'] = Title,
		[A:ORIGIN('Chapter')] = Chapter,
		[Periodical_origin] = Periodical,
		[PublisherName_origin] = PublisherName
		});

	-- COinS metadata (see <http://ocoins.info/>) for automated parsing of citation information.
	-- handle the oddity that is cite encyclopedia and {{citation |encyclopedia=something}}. Here we presume that
	-- when Periodical, Title, and Chapter are all set, then Periodical is the book (encyclopedia) title, Title
	-- is the article title, and Chapter is a section within the article.  So, we remap 
	
	local coins_chapter = Chapter;												-- default assuming that remapping not required
	local coins_title = Title;													-- et tu
	if 'encyclopaedia' == config.CitationClass or ('citation' == config.CitationClass and utilities.is_set (Encyclopedia)) then
		if utilities.is_set (Chapter) and utilities.is_set (Title) and utilities.is_set (Periodical) then		-- if all are used then
			coins_chapter = Title;												-- remap
			coins_title = Periodical;
		end
	end
	local coins_author = a;														-- default for coins rft.au 
	if 0 < #c then																-- but if contributor list
		coins_author = c;														-- use that instead
	end
	
	local QuotePage = A['QuotePage'];
	local QuotePages = hyphen_to_dash (A['QuotePages']);

	-- this is the function call to COinS()
	local OCinSoutput = metadata.COinS({
		['Periodical'] = utilities.strip_apostrophe_markup (Periodical),		-- no markup in the metadata
		['Encyclopedia'] = Encyclopedia,										-- just a flag; content ignored by ~/COinS
		['Chapter'] = metadata.make_coins_title (coins_chapter, ScriptChapter),	-- Chapter and ScriptChapter stripped of bold / italic wiki-markup
		['Degree'] = Degree;													-- cite thesis only
		['Title'] = metadata.make_coins_title (coins_title, ScriptTitle),		-- Title and ScriptTitle stripped of bold / italic wiki-markup
		['PublicationPlace'] = PublicationPlace,
		['Date'] = COinS_date.rftdate,											-- COinS_date has correctly formatted date if Date is valid;
		['Season'] = COinS_date.rftssn,
		['Quarter'] = COinS_date.rftquarter,
		['Chron'] =  COinS_date.rftchron or (not COinS_date.rftdate and Date) or '',	-- chron but if not set and invalid date format use Date; keep this last bit?
		['Series'] = Series,
		['Volume'] = Volume,
		['Issue'] = Issue,
		['Pages'] = coins_pages or metadata.get_coins_pages (first_set ({Sheet, Sheets, Page, Pages, At, QuotePage, QuotePages}, 7)),	-- pages stripped of external links
		['Edition'] = Edition,
		['PublisherName'] = PublisherName or Newsgroup,							-- any apostrophe markup already removed from PublisherName
		['URL'] = first_set ({ChapterURL, URL}, 2),
		['Authors'] = coins_author,
		['ID_list'] = ID_list_coins,
		['RawPage'] = this_page.prefixedText,
	}, config.CitationClass);

	-- Account for the oddities that are {{cite arxiv}}, {{cite biorxiv}}, {{cite citeseerx}}, and {{cite ssrn}} AFTER generation of COinS data.
	if utilities.in_array (config.CitationClass, whitelist.preprint_template_list) then	-- we have set rft.jtitle in COinS to arXiv, bioRxiv, CiteSeerX, or ssrn now unset so it isn't displayed
		Periodical = '';														-- periodical not allowed in these templates; if article has been published, use cite journal
	end

	-- special case for cite newsgroup.  Do this after COinS because we are modifying Publishername to include some static text
	if 'newsgroup' == config.CitationClass and utilities.is_set (Newsgroup) then
		PublisherName = utilities.substitute (cfg.messages['newsgroup'], external_link( 'news:' .. Newsgroup, Newsgroup, Newsgroup_origin, nil ));
	end

	local Editors;
	local EditorCount;															-- used only for choosing {ed.) or (eds.) annotation at end of editor name-list
	local Contributors;															-- assembled contributors name list
	local contributor_etal;
	local Translators;															-- assembled translators name list
	local translator_etal;
	local t = {};																-- translators list from |translator-lastn= / translator-firstn= pairs
	t = extract_names (args, 'TranslatorList');									-- fetch translator list from |translatorn= / |translator-lastn=, -firstn=, -linkn=, -maskn=
	local Interviewers;															
	local interviewers_list = {};					
	interviewers_list = extract_names (args, 'InterviewerList');				-- process preferred interviewers parameters
	local interviewer_etal;
	
	-- Now perform various field substitutions.
	-- We also add leading spaces and surrounding markup and punctuation to the
	-- various parts of the citation, but only when they are non-nil.
	do
		local last_first_list;
		local control = { 
			format = NameListStyle,												-- empty string or 'vanc'
			maximum = nil,														-- as if display-authors or display-editors not set
			mode = Mode
		};

		do																		-- do editor name list first because the now unsupported coauthors used to modify control table
			control.maximum , editor_etal = get_display_names (A['DisplayEditors'], #e, 'editors', editor_etal, A:ORIGIN ('DisplayEditors'));
			Editors, EditorCount = list_people (control, e, editor_etal);

			if 1 == EditorCount and (true == editor_etal or 1 < #e) then		-- only one editor displayed but includes etal then 
				EditorCount = 2;												-- spoof to display (eds.) annotation
			end
		end
		do																		-- now do interviewers
			control.maximum, interviewer_etal = get_display_names (A['DisplayInterviewers'], #interviewers_list, 'interviewers', interviewer_etal, A:ORIGIN ('DisplayInterviewers'));
			Interviewers = list_people (control, interviewers_list, interviewer_etal);
		end
		do																		-- now do translators
			control.maximum, translator_etal = get_display_names (A['DisplayTranslators'], #t, 'translators', translator_etal, A:ORIGIN ('DisplayTranslators'));
			Translators = list_people (control, t, translator_etal);
		end
		do																		-- now do contributors
			control.maximum, contributor_etal = get_display_names (A['DisplayContributors'], #c, 'contributors', contributor_etal, A:ORIGIN ('DisplayContributors'));
			Contributors = list_people (control, c, contributor_etal);
		end
		do																		-- now do authors
			control.maximum, author_etal = get_display_names (A['DisplayAuthors'], #a, 'authors', author_etal, A:ORIGIN ('DisplayAuthors'));

			last_first_list = list_people (control, a, author_etal);

			if utilities.is_set (Authors) then
				Authors, author_etal = name_has_etal (Authors, author_etal, false, 'authors');	-- find and remove variations on et al.
				if author_etal then
					Authors = Authors .. ' ' .. cfg.messages['et al'];			-- add et al. to authors parameter
				end
			else
				Authors = last_first_list;										-- either an author name list or an empty string
			end
		end																		-- end of do
	
		if utilities.is_set (Authors) and utilities.is_set (Collaboration) then
			Authors = Authors .. ' (' .. Collaboration .. ')';					-- add collaboration after et al.
		end

	end

	local ConferenceFormat = A['ConferenceFormat'];
	local ConferenceURL = A['ConferenceURL'];
	ConferenceFormat = style_format (ConferenceFormat, ConferenceURL, 'conference-format', 'conference-url');
	Format = style_format (Format, URL, 'format', 'url');

	-- special case for chapter format so no error message or cat when chapter not supported
	if not (utilities.in_array (config.CitationClass, {'web', 'news', 'journal', 'magazine', 'pressrelease', 'podcast', 'newsgroup', 'arxiv', 'biorxiv', 'citeseerx', 'ssrn'}) or
		('citation' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and not utilities.is_set (Encyclopedia))) then
			ChapterFormat = style_format (ChapterFormat, ChapterURL, 'chapter-format', 'chapter-url');
	end

	if not utilities.is_set (URL) then
		if utilities.in_array (config.CitationClass, {"web", "podcast", "mailinglist"}) or		-- |url= required for cite web, cite podcast, and cite mailinglist
			('citation' == config.CitationClass and ('website' == Periodical_origin or 'script-website' == ScriptPeriodical_origin)) then	-- and required for {{citation}} with |website= or |script-website=
				table.insert( z.message_tail, { utilities.set_message ( 'err_cite_web_url', {}, true ) } );
		end
		
		-- do we have |accessdate= without either |url= or |chapter-url=?
		if utilities.is_set (AccessDate) and not utilities.is_set (ChapterURL) then		-- ChapterURL may be set when URL is not set;
			table.insert( z.message_tail, { utilities.set_message ( 'err_accessdate_missing_url', {}, true ) } );
			AccessDate = '';
		end
	end

	local UrlStatus = is_valid_parameter_value (A['UrlStatus'], A:ORIGIN('UrlStatus'), cfg.keywords_lists['url-status'], '');
	local OriginalURL
	local OriginalURL_origin
	local OriginalFormat
	local OriginalAccess;
	UrlStatus = UrlStatus:lower();												-- used later when assembling archived text
	if utilities.is_set ( ArchiveURL ) then
		if utilities.is_set (ChapterURL) then 									-- if chapter-url= is set apply archive url to it
			OriginalURL = ChapterURL;											-- save copy of source chapter's url for archive text
			OriginalURL_origin = ChapterURL_origin;								-- name of |chapter-url= parameter for error messages
			OriginalFormat = ChapterFormat;										-- and original |chapter-format=

			if 'live' ~= UrlStatus then
				ChapterURL = ArchiveURL											-- swap-in the archive's URL
				ChapterURL_origin = A:ORIGIN('ArchiveURL')						-- name of |archive-url= parameter for error messages
				ChapterFormat = ArchiveFormat or '';							-- swap in archive's format
				ChapterUrlAccess = nil;											-- restricted access levels do not make sense for archived URLs
			end
		elseif utilities.is_set (URL) then
			OriginalURL = URL;													-- save copy of original source URL
			OriginalURL_origin = URL_origin;									-- name of URL parameter for error messages
			OriginalFormat = Format; 											-- and original |format=
			OriginalAccess = UrlAccess;

			if 'live' ~= UrlStatus then											-- if URL set then |archive-url= applies to it
				URL = ArchiveURL												-- swap-in the archive's URL
				URL_origin = A:ORIGIN('ArchiveURL')								-- name of archive URL parameter for error messages
				Format = ArchiveFormat or '';									-- swap in archive's format
				UrlAccess = nil;												-- restricted access levels do not make sense for archived URLs
			end
 		end
	end

	if utilities.in_array (config.CitationClass, {'web', 'news', 'journal', 'magazine', 'pressrelease', 'podcast', 'newsgroup', 'arxiv', 'biorxiv', 'citeseerx', 'ssrn'}) or	-- if any of the 'periodical' cites except encyclopedia
		('citation' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and not utilities.is_set (Encyclopedia)) then
			local chap_param;
			if utilities.is_set (Chapter) then									-- get a parameter name from one of these chapter related meta-parameters
				chap_param = A:ORIGIN ('Chapter')
			elseif utilities.is_set (TransChapter) then
				chap_param = A:ORIGIN ('TransChapter')
			elseif utilities.is_set (ChapterURL) then
				chap_param = A:ORIGIN ('ChapterURL')
			elseif utilities.is_set (ScriptChapter) then
				chap_param = ScriptChapter_origin;
			else utilities.is_set (ChapterFormat)
				chap_param = A:ORIGIN ('ChapterFormat')
			end

			if utilities.is_set (chap_param) then								-- if we found one
				table.insert( z.message_tail, { utilities.set_message ( 'err_chapter_ignored', {chap_param}, true ) } );	-- add error message
				Chapter = '';													-- and set them to empty string to be safe with concatenation
				TransChapter = '';
				ChapterURL = '';
				ScriptChapter = '';
				ChapterFormat = '';
			end
	else																		-- otherwise, format chapter / article title
		local no_quotes = false;												-- default assume that we will be quoting the chapter parameter value
		if utilities.is_set (Contribution) and 0 < #c then						-- if this is a contribution with contributor(s)
			if utilities.in_array (Contribution:lower(), cfg.keywords_lists.contribution) then	-- and a generic contribution title
				no_quotes = true;												-- then render it unquoted
			end
		end

		Chapter = format_chapter_title (ScriptChapter, ScriptChapter_origin, Chapter, Chapter_origin, TransChapter, TransChapter_origin, ChapterURL, ChapterURL_origin, no_quotes, ChapterUrlAccess);		-- Contribution is also in Chapter
		if utilities.is_set (Chapter) then
			Chapter = Chapter .. ChapterFormat ;
			if 'map' == config.CitationClass and utilities.is_set (TitleType) then
				Chapter = Chapter .. ' ' .. TitleType;							-- map annotation here; not after title
			end
			Chapter = Chapter .. sepc .. ' ';
		elseif utilities.is_set (ChapterFormat) then							-- |chapter= not set but |chapter-format= is so ...
			Chapter = ChapterFormat .. sepc .. ' ';								-- ... ChapterFormat has error message, we want to see it
		end
	end

	-- Format main title
	local plain_title = false;
	local accept_title;
	Title, accept_title = utilities.has_accept_as_written (Title, true);		-- remove accept-this-as-written markup when it wraps all of <Title>
	if accept_title and ('' == Title) then										-- only support forced empty for now "(())"
		Title = cfg.messages['notitle'];										-- replace by predefined "No title" message
			-- TODO: utilities.set_message ( 'err_redundant_parameters', ...);	-- issue proper error message instead of muting	 
			ScriptTitle = '';													-- just mute for now	 
			TransTitle = '';													-- just mute for now
 		plain_title = true;														-- suppress text decoration for descriptive title
		utilities.set_message ('maint_untitled');								-- add maint cat
	end

	if not accept_title then -- <Title> not wrapped in accept-as-written markup
		if '...' == Title:sub (-3) then											-- if ellipsis is the last three characters of |title=
			Title = Title:gsub ('(%.%.%.)%.+$', '%1');							-- limit the number of dots to three
		elseif not mw.ustring.find (Title, '%.%s*%a%.$') and					-- end of title is not a 'dot-(optional space-)letter-dot' initialism ...
			not mw.ustring.find (Title, '%s+%a%.$') then						-- ...and not a 'space-letter-dot' initial (''Allium canadense'' L.)
				Title = mw.ustring.gsub(Title, '%' .. sepc .. '$', '');			-- remove any trailing separator character; sepc and ms.ustring() here for languages that use multibyte separator characters
		end

		if utilities.is_set (ArchiveURL) and is_archived_copy (Title) then
			utilities.set_message ('maint_archived_copy');						-- add maintenance category before we modify the content of Title
		end

		if is_generic_title (Title) then
			table.insert (z.message_tail, {utilities.set_message ( 'err_generic_title', {}, true ) } );	-- set an error message
		end
	end

	if (not plain_title) and (utilities.in_array (config.CitationClass, {'web', 'news', 'journal', 'magazine', 'pressrelease', 'podcast', 'newsgroup', 'mailinglist', 'interview', 'arxiv', 'biorxiv', 'citeseerx', 'ssrn'}) or
		('citation' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)) and not utilities.is_set (Encyclopedia)) or
		('map' == config.CitationClass and (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical)))) then		-- special case for cite map when the map is in a periodical treat as an article
			Title = kern_quotes (Title);										-- if necessary, separate title's leading and trailing quote marks from module provided quote marks
			Title = utilities.wrap_style ('quoted-title', Title);
			Title = script_concatenate (Title, ScriptTitle, 'script-title');	-- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped
			TransTitle = utilities.wrap_style ('trans-quoted-title', TransTitle );
	elseif plain_title or ('report' == config.CitationClass) then								-- no styling for cite report and descriptive titles (otherwise same as above)
		Title = script_concatenate (Title, ScriptTitle, 'script-title');		-- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped
		TransTitle = utilities.wrap_style ('trans-quoted-title', TransTitle );				-- for cite report, use this form for trans-title
	else
		Title = utilities.wrap_style ('italic-title', Title);
		Title = script_concatenate (Title, ScriptTitle, 'script-title');		-- <bdi> tags, lang attribute, categorization, etc.; must be done after title is wrapped
		TransTitle = utilities.wrap_style ('trans-italic-title', TransTitle);
	end

	local TransError = "";
	if utilities.is_set (TransTitle) then
		if utilities.is_set (Title) then
			TransTitle = " " .. TransTitle;
		else
			TransError = " " .. utilities.set_message ( 'err_trans_missing_title', {'title'} );
		end
	end

	if utilities.is_set (Title) then											-- TODO: is this the right place to be making Wikisource URLs?
		if utilities.is_set (TitleLink) and utilities.is_set (URL) then
			table.insert( z.message_tail, { utilities.set_message ( 'err_wikilink_in_url', {}, true ) } );	-- set an error message because we can't have both
			TitleLink = '';														-- unset
		end
	
		if not utilities.is_set (TitleLink) and utilities.is_set (URL) then
			Title = external_link (URL, Title, URL_origin, UrlAccess) .. TransTitle .. TransError .. Format;
			URL = '';															-- unset these because no longer needed
			Format = "";
		elseif utilities.is_set (TitleLink) and not utilities.is_set (URL) then
			local ws_url;
			ws_url = wikisource_url_make (TitleLink);							-- ignore ws_label return; not used here
			if ws_url then
				Title = external_link (ws_url, Title .. '&nbsp;', 'ws link in title-link');	-- space char after Title to move icon away from italic text; TODO: a better way to do this?
				Title = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], TitleLink, Title});				
				Title = Title .. TransTitle .. TransError;
			else
				Title = utilities.make_wikilink (TitleLink, Title) .. TransTitle .. TransError;
			end
		else
			local ws_url, ws_label, L;											-- Title has italic or quote markup by the time we get here which causes is_wikilink() to return 0 (not a wikilink)
			ws_url, ws_label, L = wikisource_url_make (Title:gsub('^[\'"]*(.-)[\'"]*$', '%1'));	-- make ws URL from |title= interwiki link (strip italic or quote markup); link portion L becomes tooltip label
			if ws_url then
				Title = Title:gsub ('%b[]', ws_label);							-- replace interwiki link with ws_label to retain markup
				Title = external_link (ws_url, Title .. '&nbsp;', 'ws link in title');	-- space char after Title to move icon away from italic text; TODO: a better way to do this?
				Title = utilities.substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, Title});				
				Title = Title .. TransTitle .. TransError;
			else
				Title = Title .. TransTitle .. TransError;
			end
		end
	else
		Title = TransTitle .. TransError;
	end

	if utilities.is_set (Place) then
		Place = " " .. wrap_msg ('written', Place, use_lowercase) .. sepc .. " ";
	end

	local ConferenceURL_origin = A:ORIGIN('ConferenceURL');						-- get name of parameter that holds ConferenceURL
	if utilities.is_set (Conference) then
		if utilities.is_set (ConferenceURL) then
			Conference = external_link( ConferenceURL, Conference, ConferenceURL_origin, nil );
		end
		Conference = sepc .. " " .. Conference .. ConferenceFormat;
	elseif utilities.is_set (ConferenceURL) then
		Conference = sepc .. " " .. external_link( ConferenceURL, nil, ConferenceURL_origin, nil );
	end

	local Position = '';
	if not utilities.is_set (Position) then
		local Minutes = A['Minutes'];
		local Time = A['Time'];

		if utilities.is_set (Minutes) then
			if utilities.is_set (Time) then
				table.insert( z.message_tail, { utilities.set_message ( 'err_redundant_parameters', {utilities.wrap_style ('parameter', 'minutes') .. ' and ' .. utilities.wrap_style ('parameter', 'time')}, true ) } );
			end
			Position = " " .. Minutes .. " " .. cfg.messages['minutes'];
		else
			if utilities.is_set (Time) then
				local TimeCaption = A['TimeCaption']
				if not utilities.is_set (TimeCaption) then
					TimeCaption = cfg.messages['event'];
					if sepc ~= '.' then
						TimeCaption = TimeCaption:lower();
					end
				end
				Position = " " .. TimeCaption .. " " .. Time;
			end
		end
	else
		Position = " " .. Position;
		At = '';
	end

	Page, Pages, Sheet, Sheets = format_pages_sheets (Page, Pages, Sheet, Sheets, config.CitationClass, Periodical_origin, sepc, NoPP, use_lowercase);

	At = utilities.is_set (At) and (sepc .. " " .. At) or "";
	Position = utilities.is_set (Position) and (sepc .. " " .. Position) or "";
	if config.CitationClass == 'map' then
		local Sections = A['Sections'];											-- Section (singular) is an alias of Chapter so set earlier
		local Inset = A['Inset'];
		
		if utilities.is_set ( Inset ) then
			Inset = sepc .. " " .. wrap_msg ('inset', Inset, use_lowercase);
		end			

		if utilities.is_set ( Sections ) then
			Section = sepc .. " " .. wrap_msg ('sections', Sections, use_lowercase);
		elseif utilities.is_set ( Section ) then
			Section = sepc .. " " .. wrap_msg ('section', Section, use_lowercase);
		end
		At = At .. Inset .. Section;		
	end	

	local Others = A['Others'];
	if utilities.is_set (Others) and 0 == #a and 0 == #e then					-- add maint cat when |others= has value and used without |author=, |editor=
		if config.CitationClass == "AV-media-notes"
		or config.CitationClass == "audio-visual" then							-- special maint for AV/M which has a lot of 'false' positives right now
			utilities.set_message ('maint_others_avm')
		else
			utilities.set_message ('maint_others');
		end
	end
	Others = utilities.is_set (Others) and (sepc .. " " .. Others) or "";
	
	if utilities.is_set (Translators) then
		Others = safe_join ({sepc .. ' ', wrap_msg ('translated', Translators, use_lowercase), Others}, sepc);
	end
	if utilities.is_set (Interviewers) then
		Others = safe_join ({sepc .. ' ', wrap_msg ('interview', Interviewers, use_lowercase), Others}, sepc);
	end
	
	local TitleNote = A['TitleNote'];
	TitleNote = utilities.is_set (TitleNote) and (sepc .. " " .. TitleNote) or "";
	if utilities.is_set (Edition) then
		if Edition:match ('%f[%a][Ee]d%n?%.?$') or Edition:match ('%f[%a][Ee]dition$') then -- Ed, ed, Ed., ed., Edn, edn, Edn., edn.
			table.insert( z.message_tail, { utilities.set_message ( 'err_extra_text_edition')}); -- add error
		end
		Edition = " " .. wrap_msg ('edition', Edition);
	else
		Edition = '';
	end

	Series = utilities.is_set (Series) and wrap_msg ('series', {sepc, Series}) or "";	-- not the same as SeriesNum
	local Agency = A['Agency'];
	Agency = utilities.is_set (Agency) and wrap_msg ('agency', {sepc, Agency}) or "";
	Volume = format_volume_issue (Volume, Issue, config.CitationClass, Periodical_origin, sepc, use_lowercase);

	if utilities.is_set (AccessDate) then
		local retrv_text = " " .. cfg.messages['retrieved']

		AccessDate = nowrap_date (AccessDate);									-- wrap in nowrap span if date in appropriate format
		if (sepc ~= ".") then retrv_text = retrv_text:lower() end				-- if mode is cs2, lower case
		AccessDate = utilities.substitute (retrv_text, AccessDate);				-- add retrieved text

		AccessDate = utilities.substitute (cfg.presentation['accessdate'], {sepc, AccessDate});	-- allow editors to hide accessdates
	end
	
	if utilities.is_set (ID) then ID = sepc .. " " .. ID; end
	
	local Docket = A['Docket'];
   	if "thesis" == config.CitationClass and utilities.is_set (Docket) then
		ID = sepc .. " Docket " .. Docket .. ID;
	end
   	if "report" == config.CitationClass and utilities.is_set (Docket) then		-- for cite report when |docket= is set
		ID = sepc .. ' ' .. Docket;												-- overwrite ID even if |id= is set
	end

	if utilities.is_set (URL) then
		URL = " " .. external_link( URL, nil, URL_origin, UrlAccess );
	end

	local Quote = A['Quote'];
	local TransQuote = A['TransQuote'];
	local ScriptQuote = A['ScriptQuote'];
	if utilities.is_set (Quote) or utilities.is_set (TransQuote) or utilities.is_set (ScriptQuote) then

		if utilities.is_set (Quote) then
			if Quote:sub(1, 1) == '"' and Quote:sub(-1, -1) == '"' then			-- if first and last characters of quote are quote marks
				Quote = Quote:sub(2, -2);										-- strip them off
			end
		end

		Quote = utilities.wrap_style ('quoted-text', Quote );					-- wrap in <q>...</q> tags
	
		if utilities.is_set (ScriptQuote) then
			Quote = script_concatenate (Quote, ScriptQuote, 'script-quote');	-- <bdi> tags, lang attribute, categorization, etc.; must be done after quote is wrapped
		end

		if utilities.is_set (TransQuote) then
			if TransQuote:sub(1, 1) == '"' and TransQuote:sub(-1, -1) == '"' then -- if first and last characters of |trans-quote are quote marks
				TransQuote = TransQuote:sub(2, -2); -- strip them off
			end
			Quote = Quote .. " " .. utilities.wrap_style ('trans-quoted-title', TransQuote );
		end

		if utilities.is_set (QuotePage) or utilities.is_set (QuotePages) then	-- add page prefix
			local quote_prefix = '';
			if utilities.is_set (QuotePage) then
				extra_text_in_page_check (QuotePage, 'quote-page');				-- add to maint cat if |quote-page= value begins with what looks like p., pp., etc.
				if not NoPP then
					quote_prefix = utilities.substitute (cfg.messages['p-prefix'], {sepc, QuotePage}), '', '', '';
				else
					quote_prefix = utilities.substitute (cfg.messages['nopp'], {sepc, QuotePage}), '', '', '';
				end
			elseif utilities.is_set (QuotePages) then
				extra_text_in_page_check (QuotePages, 'quote-pages');			-- add to maint cat if |quote-pages= value begins with what looks like p., pp., etc.
				if tonumber(QuotePages) ~= nil and not NoPP then				-- if only digits, assume single page
					quote_prefix = utilities.substitute (cfg.messages['p-prefix'], {sepc, QuotePages}), '', '';
				elseif not NoPP then
					quote_prefix = utilities.substitute (cfg.messages['pp-prefix'], {sepc, QuotePages}), '', '';
				else
					quote_prefix = utilities.substitute (cfg.messages['nopp'], {sepc, QuotePages}), '', '';
				end
			end
                        
			Quote = quote_prefix .. ": " .. Quote;
		else
			Quote = sepc .. " " .. Quote;
		end

		PostScript = "";														-- cs1|2 does not supply terminal punctuation when |quote= is set
	end
	
	-- We check length of PostScript here because it will have been nuked by
	-- the quote parameters. We'd otherwise emit a message even if there wasn't
	-- a displayed postscript.
	-- TODO: Should the max size (1) be configurable?
	-- TODO: Should we check a specific pattern?
	if utilities.is_set(PostScript) and mw.ustring.len(PostScript) > 1 then
		utilities.set_message('maint_postscript')
	end
	
	local Archived
	if utilities.is_set (ArchiveURL) then
		local arch_text;
		if not utilities.is_set (ArchiveDate) then
			ArchiveDate = utilities.set_message ('err_archive_missing_date');
		end
		if "live" == UrlStatus then
			arch_text = cfg.messages['archived'];
			if sepc ~= "." then arch_text = arch_text:lower() end
			Archived = sepc .. " " .. utilities.substitute ( cfg.messages['archived-live'],
				{ external_link( ArchiveURL, arch_text, A:ORIGIN('ArchiveURL'), nil ) .. ArchiveFormat, ArchiveDate } );
			if not utilities.is_set (OriginalURL) then
				Archived = Archived .. " " .. utilities.set_message ('err_archive_missing_url');							   
			end
		elseif utilities.is_set (OriginalURL) then								-- UrlStatus is empty, 'dead', 'unfit', 'usurped', 'bot: unknown'
			if utilities.in_array (UrlStatus, {'unfit', 'usurped', 'bot: unknown'}) then
				arch_text = cfg.messages['archived-unfit'];
				if sepc ~= "." then arch_text = arch_text:lower() end
				Archived = sepc .. " " .. arch_text .. ArchiveDate;				-- format already styled
				if 'bot: unknown' == UrlStatus then
					utilities.set_message ('maint_bot_unknown');				-- and add a category if not already added
				else
					utilities.set_message ('maint_unfit');						-- and add a category if not already added
				end
			else																-- UrlStatus is empty, 'dead'
				arch_text = cfg.messages['archived-dead'];
				if sepc ~= "." then arch_text = arch_text:lower() end
				Archived = sepc .. " " .. utilities.substitute ( arch_text,
					{ external_link( OriginalURL, cfg.messages['original'], OriginalURL_origin, OriginalAccess ) .. OriginalFormat, ArchiveDate } );	-- format already styled
			end	
		else																	-- OriginalUrl not set
			arch_text = cfg.messages['archived-missing'];
			if sepc ~= "." then arch_text = arch_text:lower() end
			Archived = sepc .. " " .. utilities.substitute ( arch_text, 
				{ utilities.set_message ('err_archive_missing_url'), ArchiveDate } );
		end
	elseif utilities.is_set (ArchiveFormat) then
		Archived = ArchiveFormat;												-- if set and ArchiveURL not set ArchiveFormat has error message
	else
		Archived = ""
	end
	
	local Lay = '';
	local LaySource = A['LaySource'];
	local LayURL = A['LayURL'];
	local LayFormat = A['LayFormat'];
	LayFormat = style_format (LayFormat, LayURL, 'lay-format', 'lay-url');
	if utilities.is_set (LayURL) then
		if utilities.is_set (LayDate) then LayDate = " (" .. LayDate .. ")" end
		if utilities.is_set (LaySource) then 
			LaySource = " &ndash; ''" .. utilities.safe_for_italics (LaySource) .. "''";
		else
			LaySource = "";
		end
		if sepc == '.' then
			Lay = sepc .. " " .. external_link( LayURL, cfg.messages['lay summary'], A:ORIGIN('LayURL'), nil ) .. LayFormat .. LaySource .. LayDate
		else
			Lay = sepc .. " " .. external_link( LayURL, cfg.messages['lay summary']:lower(), A:ORIGIN('LayURL'), nil ) .. LayFormat .. LaySource .. LayDate
		end			
	elseif utilities.is_set (LayFormat) then									-- Test if |lay-format= is given without giving a |lay-url=
		Lay = sepc .. LayFormat;												-- if set and LayURL not set, then LayFormat has error message
	end

	local TranscriptURL = A['TranscriptURL']
	local TranscriptFormat = A['TranscriptFormat'];
	TranscriptFormat = style_format (TranscriptFormat, TranscriptURL, 'transcript-format', 'transcripturl');
	local Transcript = A['Transcript'];
	local TranscriptURL_origin = A:ORIGIN('TranscriptURL');						-- get name of parameter that holds TranscriptURL
	if utilities.is_set (Transcript) then
		if utilities.is_set (TranscriptURL) then
			Transcript = external_link( TranscriptURL, Transcript, TranscriptURL_origin, nil );
		end
		Transcript = sepc .. ' ' .. Transcript .. TranscriptFormat;
	elseif utilities.is_set (TranscriptURL) then
		Transcript = external_link( TranscriptURL, nil, TranscriptURL_origin, nil );
	end

	local Publisher;
	if utilities.is_set (PublicationDate) then
		PublicationDate = wrap_msg ('published', PublicationDate);
	end
	if utilities.is_set (PublisherName) then
		if utilities.is_set (PublicationPlace) then
			Publisher = sepc .. " " .. PublicationPlace .. ": " .. PublisherName .. PublicationDate;
		else
			Publisher = sepc .. " " .. PublisherName .. PublicationDate;  
		end			
	elseif utilities.is_set (PublicationPlace) then 
		Publisher= sepc .. " " .. PublicationPlace .. PublicationDate;
	else 
		Publisher = PublicationDate;
	end
	
	local TransPeriodical =  A['TransPeriodical'];
	local TransPeriodical_origin =  A:ORIGIN ('TransPeriodical');
	-- Several of the above rely upon detecting this as nil, so do it last.
	if (utilities.is_set (Periodical) or utilities.is_set (ScriptPeriodical) or utilities.is_set (TransPeriodical)) then
		if utilities.is_set (Title) or utilities.is_set (TitleNote) then 
			Periodical = sepc .. " " .. format_periodical (ScriptPeriodical, ScriptPeriodical_origin, Periodical, TransPeriodical, TransPeriodical_origin);
		else 
			Periodical = format_periodical (ScriptPeriodical, ScriptPeriodical_origin, Periodical, TransPeriodical, TransPeriodical_origin);
		end
	end
	
	local Language = A['Language'];
	if utilities.is_set (Language) then
		Language = language_parameter (Language);								-- format, categories, name from ISO639-1, etc.
	else
		Language='';															-- language not specified so make sure this is an empty string;
	--[[ TODO: need to extract the wrap_msg from language_parameter
	so that we can solve parentheses bunching problem with Format/Language/TitleType
	]]
	end

	--[[
	Handle the oddity that is cite speech.  This code overrides whatever may be the value assigned to TitleNote (through |department=) and forces it to be " (Speech)" so that
	the annotation directly follows the |title= parameter value in the citation rather than the |event= parameter value (if provided).
	]]
	if "speech" == config.CitationClass then									-- cite speech only
		TitleNote = " (Speech)";												-- annotate the citation
		if utilities.is_set (Periodical) then									-- if Periodical, perhaps because of an included |website= or |journal= parameter 
			if utilities.is_set (Conference) then								-- and if |event= is set
				Conference = Conference .. sepc .. " ";							-- then add appropriate punctuation to the end of the Conference variable before rendering
			end
		end
	end

	-- Piece all bits together at last.  Here, all should be non-nil.
	-- We build things this way because it is more efficient in LUA
	-- not to keep reassigning to the same string variable over and over.

	local tcommon;
	local tcommon2;																-- used for book cite when |contributor= is set
	
	if utilities.in_array (config.CitationClass, {"journal", "citation"}) and utilities.is_set (Periodical) then
		if utilities.is_set (Others) then Others = safe_join ({Others, sepc .. " "}, sepc) end		-- add terminal punctuation & space; check for dup sepc; TODO why do we need to do this here?
		tcommon = safe_join( {Others, Title, TitleNote, Conference, Periodical, Format, TitleType, Series, Language, Edition, Publisher, Agency, Volume}, sepc );
	elseif utilities.in_array (config.CitationClass, {"book", "citation"}) and not utilities.is_set (Periodical) then		-- special cases for book cites
		if utilities.is_set (Contributors) then									-- when we are citing foreword, preface, introduction, etc.
			tcommon = safe_join( {Title, TitleNote}, sepc );					-- author and other stuff will come after this and before tcommon2
			tcommon2 = safe_join( {Conference, Periodical, Format, TitleType, Series, Language, Volume, Others, Edition, Publisher, Agency}, sepc );
		else
			tcommon = safe_join( {Title, TitleNote, Conference, Periodical, Format, TitleType, Series, Language, Volume, Others, Edition, Publisher, Agency}, sepc );
		end

	elseif 'map' == config.CitationClass then									-- special cases for cite map
		if utilities.is_set (Chapter) then										-- map in a book; TitleType is part of Chapter
			tcommon = safe_join( {Title, Format, Edition, Scale, Series, Language, Cartography, Others, Publisher, Volume}, sepc );
		elseif utilities.is_set (Periodical) then								-- map in a periodical
			tcommon = safe_join( {Title, TitleType, Format, Periodical, Scale, Series, Language, Cartography, Others, Publisher, Volume}, sepc );
		else																	-- a sheet or stand-alone map
			tcommon = safe_join( {Title, TitleType, Format, Edition, Scale, Series, Language, Cartography, Others, Publisher}, sepc );
		end
		
	elseif 'episode' == config.CitationClass then								-- special case for cite episode
		tcommon = safe_join( {Title, TitleNote, TitleType, Series, Language, Edition, Publisher}, sepc );

	else																		-- all other CS1 templates
		tcommon = safe_join( {Title, TitleNote, Conference, Periodical, Format, TitleType, Series, Language, 
			Volume, Others, Edition, Publisher, Agency}, sepc );
	end
	
	if #ID_list > 0 then
		ID_list = safe_join( { sepc .. " ",  table.concat( ID_list, sepc .. " " ), ID }, sepc );
	else
		ID_list = ID;
	end
	
	local Via = A['Via'];
	Via = utilities.is_set (Via) and  wrap_msg ('via', Via) or '';
	local idcommon;
	if 'audio-visual' == config.CitationClass or 'episode' == config.CitationClass then	-- special case for cite AV media & cite episode position transcript
		idcommon = safe_join( { ID_list, URL, Archived, Transcript, AccessDate, Via, Lay, Quote }, sepc );
	else
		idcommon = safe_join( { ID_list, URL, Archived, AccessDate, Via, Lay, Quote }, sepc );
	end
	
	local text;
	local pgtext = Position .. Sheet .. Sheets .. Page .. Pages .. At;

	local OrigDate = A['OrigDate'];
	OrigDate = utilities.is_set (OrigDate) and wrap_msg ('origdate', OrigDate) or '';
	if utilities.is_set (Date) then
		if utilities.is_set (Authors) or utilities.is_set (Editors) then		-- date follows authors or editors when authors not set
			Date = " (" .. Date .. ")" .. OrigDate .. sepc .. " ";				-- in parentheses
		else																	-- neither of authors and editors set
			if (string.sub(tcommon, -1, -1) == sepc) then						-- if the last character of tcommon is sepc
				Date = " " .. Date .. OrigDate;									-- Date does not begin with sepc
			else
				Date = sepc .. " " .. Date .. OrigDate;							-- Date begins with sepc
			end
		end
	end	
	if utilities.is_set (Authors) then
		if (not utilities.is_set (Date)) then									-- when date is set it's in parentheses; no Authors termination
			Authors = terminate_name_list (Authors, sepc);						-- when no date, terminate with 0 or 1 sepc and a space
		end
		if utilities.is_set (Editors) then
			local in_text = " ";
			local post_text = "";
			if utilities.is_set (Chapter) and 0 == #c then
				in_text = in_text .. cfg.messages['in'] .. " "
				if (sepc ~= '.') then
					in_text = in_text:lower()									-- lowercase for cs2
				end
			end
			if EditorCount <= 1 then
				post_text = " (" .. cfg.messages['editor'] .. ")";				-- be consistent with no-author, no-date case
			else
				post_text = " (" .. cfg.messages['editors'] .. ")";
			end
			Editors = terminate_name_list (in_text .. Editors .. post_text, sepc);	-- terminate with 0 or 1 sepc and a space
		end
		if utilities.is_set (Contributors) then									-- book cite and we're citing the intro, preface, etc.
			local by_text = sepc .. ' ' .. cfg.messages['by'] .. ' ';
			if (sepc ~= '.') then by_text = by_text:lower() end					-- lowercase for cs2
			Authors = by_text .. Authors;										-- author follows title so tweak it here
			if utilities.is_set (Editors) and utilities.is_set (Date) then		-- when Editors make sure that Authors gets terminated
				Authors = terminate_name_list (Authors, sepc);					-- terminate with 0 or 1 sepc and a space
			end
			if (not utilities.is_set (Date)) then								-- when date is set it's in parentheses; no Contributors termination
				Contributors = terminate_name_list (Contributors, sepc);		-- terminate with 0 or 1 sepc and a space
			end
			text = safe_join( {Contributors, Date, Chapter, tcommon, Authors, Place, Editors, tcommon2, pgtext, idcommon }, sepc );
		else
			text = safe_join( {Authors, Date, Chapter, Place, Editors, tcommon, pgtext, idcommon }, sepc );
		end
	elseif utilities.is_set (Editors) then
		if utilities.is_set (Date) then
			if EditorCount <= 1 then
				Editors = Editors .. ", " .. cfg.messages['editor'];
			else
				Editors = Editors .. ", " .. cfg.messages['editors'];
			end
		else
			if EditorCount <= 1 then
				Editors = Editors .. " (" .. cfg.messages['editor'] .. ")" .. sepc .. " "
			else
				Editors = Editors .. " (" .. cfg.messages['editors'] .. ")" .. sepc .. " "
			end
		end
		text = safe_join( {Editors, Date, Chapter, Place, tcommon, pgtext, idcommon}, sepc );
	else
		if utilities.in_array (config.CitationClass, {"journal", "citation"}) and utilities.is_set (Periodical) then
			text = safe_join( {Chapter, Place, tcommon, pgtext, Date, idcommon}, sepc );
		else
			text = safe_join( {Chapter, Place, tcommon, Date, pgtext, idcommon}, sepc );
		end
	end
	
	if utilities.is_set (PostScript) and PostScript ~= sepc then
		text = safe_join( {text, sepc}, sepc ); 								-- Deals with italics, spaces, etc.
		text = text:sub(1, -sepc:len() - 1);
	end	
	
	text = safe_join( {text, PostScript}, sepc );

	-- Now enclose the whole thing in a <cite> element
	local options = {};
	
	if utilities.is_set (config.CitationClass) and config.CitationClass ~= "citation" then
		options.class = string.format ('%s %s %s', 'citation', config.CitationClass, utilities.is_set (Mode) and Mode or 'cs1');	-- class=citation required for blue highlight when used with |ref=
	else
		options.class = string.format ('%s %s', 'citation', utilities.is_set (Mode) and Mode or 'cs2');
	end

	local Ref = A['Ref'];
	if 'harv' == Ref then														-- need to check this before setting to default
		utilities.set_message ('maint_ref_harv');								-- add maint cat to identify templates that have this now-extraneous param value
	elseif not utilities.is_set (Ref) then
		Ref = 'harv';															-- set as default when not set externally
	end
	if 'none' ~= cfg.keywords_xlate[Ref:lower()] then
		local id = Ref
		local namelist = {};													-- holds selected contributor, author, editor name list
		local year = first_set ({Year, anchor_year}, 2);						-- Year first for legacy citations and for YMD dates that require disambiguation

		if #c > 0 then															-- if there is a contributor list
			namelist = c;														-- select it
		elseif #a > 0 then														-- or an author list
			namelist = a;
		elseif #e > 0 then														-- or an editor list
			namelist = e;
		end
		local citeref_id
		if #namelist > 0 then													-- if there are names in namelist
			citeref_id = make_citeref_id (namelist, year);						-- go make the CITEREF anchor
		else
			citeref_id = '';													-- unset
		end
		if citeref_id == Ref then
			utilities.set_message ('maint_ref_duplicates_default');
		end
		if 'harv' == Ref then
			id = citeref_id
		end
		options.id = id;
	end
	
	if string.len(text:gsub("<span[^>/]*>(.-)</span>", "%1"):gsub("%b<>", "")) <= 2 then	-- remove <span> tags and other HTML-like markup; then get length of what remains
		z.error_categories = {};
		text = utilities.set_message ('err_empty_citation');
		z.message_tail = {};
	end
	
	local render = {};															-- here we collect the final bits for concatenation into the rendered citation

	if utilities.is_set (options.id) then										-- here we wrap the rendered citation in <cite ...>...</cite> tags
		table.insert (render, utilities.substitute (cfg.presentation['cite-id'], {mw.uri.anchorEncode(options.id), mw.text.nowiki(options.class), text}));	-- when |ref= is set
	else
		table.insert (render, utilities.substitute (cfg.presentation['cite'], {mw.text.nowiki(options.class), text}));	-- all other cases
	end		

	table.insert (render, utilities.substitute (cfg.presentation['ocins'], {OCinSoutput}));	-- append metadata to the citation

	if 0 ~= #z.message_tail then
		table.insert (render, ' ');
		for i,v in ipairs( z.message_tail ) do
			if utilities.is_set (v[1]) then
				if i == #z.message_tail then
					table.insert (render, utilities.error_comment ( v[1], v[2] ));
				else
					table.insert (render, utilities.error_comment ( v[1] .. "; ", v[2] ));
				end
			end
		end
	end

	if 0 ~= #z.maintenance_cats then
		local maint_msgs = {};													-- here we collect all of the maint messages
		for _, v in ipairs( z.maintenance_cats ) do								-- append maintenance categories
			local maint = {};													-- here we assemble a maintenence message
			table.insert (maint, v);											-- maint msg is the category name
			table.insert (maint, ' (');											-- open the link text
			table.insert (maint, utilities.substitute (cfg.messages[':cat wikilink'], {v}));	-- add the link
			table.insert (maint, ')');											-- and close it
			table.insert (maint_msgs, table.concat (maint));					-- assemble new maint message and add it to the maint_msgs table
		end
		table.insert (render, utilities.substitute (cfg.presentation['hidden-maint'], table.concat (maint_msgs, ' ')));	-- wrap the group of maint message with proper presentation and save
	end
	
	if not no_tracking_cats then
		for _, v in ipairs( z.error_categories ) do								-- append error categories
			table.insert (render, utilities.substitute (cfg.messages['cat wikilink'], {v}));
		end
		for _, v in ipairs( z.maintenance_cats ) do								-- append maintenance categories
			table.insert (render, utilities.substitute (cfg.messages['cat wikilink'], {v}));
		end
		for _, v in ipairs( z.properties_cats ) do								-- append properties categories
			table.insert (render, utilities.substitute (cfg.messages['cat wikilink'], {v}));
		end
	end

	return table.concat (render);	
end


--[[--------------------------< V A L I D A T E >--------------------------------------------------------------

Looks for a parameter's name in one of several whitelists.

Parameters in the whitelist can have three values:
	true - active, supported parameters
	false - deprecated, supported parameters
	nil - unsupported parameters
	
]]

local function validate (name, cite_class, empty)
	local name = tostring (name);
	local enum_name;															-- for enumerated parameters, is name with enumerator replaced with '#'
	local state;
	local function state_test (state, name)										-- local function to do testing of state values
		if true == state then return true; end									-- valid actively supported parameter
		if false == state then
			if empty then return nil; end										-- empty deprecated parameters are treated as unknowns
			deprecated_parameter (name);										-- parameter is deprecated but still supported
			return true;
		end
		if 'discouraged' == state then
			discouraged_parameter (name);										-- parameter is discouraged but still supported
			return true;
		end
		return nil;
	end		

	if name:find ('#') then														-- # is a cs1|2 reserved character so parameters with # not permitted
		return nil;
	end

	if utilities.in_array (cite_class, whitelist.preprint_template_list ) then	-- limited parameter sets allowed for these templates
		state = whitelist.limited_basic_arguments[name];
		if true == state_test (state, name) then return true; end

		state = whitelist.preprint_arguments[cite_class][name];					-- look in the parameter-list for the template identified by cite_class
		if true == state_test (state, name) then return true; end

																				-- limited enumerated parameters list
		enum_name = name:gsub("%d+", "#" );										-- replace digit(s) with # (last25 becomes last#) (mw.ustring because non-Western 'local' digits)
		state = whitelist.limited_numbered_arguments[enum_name];
		if true == state_test (state, name) then return true; end

		return false;															-- not supported because not found or name is set to nil
	end																			-- end limited parameter-set templates

	if utilities.in_array (cite_class, whitelist.unique_param_template_list) then 	-- experiment for template-specific parameters for templates that accept parameters from the basic argument list
		state = whitelist.unique_arguments[cite_class][name];					-- look in the template-specific parameter-lists for the template identified by cite_class
		if true == state_test (state, name) then return true; end
	end																			-- if here, fall into general validation
		
	state = whitelist.basic_arguments[name];									-- all other templates; all normal parameters allowed
	if true == state_test (state, name) then return true; end

																				-- all enumerated parameters allowed
	enum_name = name:gsub("%d+", "#" );											-- replace digit(s) with # (last25 becomes last#) (mw.ustring because non-Western 'local' digits)
	state = whitelist.numbered_arguments[enum_name];
	if true == state_test (state, name) then return true; end

	return false;																-- not supported because not found or name is set to nil
end


--[=[-------------------------< I N T E R _ W I K I _ C H E C K >----------------------------------------------

check <value> for inter-language interwiki-link markup.  <prefix> must be a MediaWiki-recognized language
code.  when these values have the form (without leading colon):
	[[<prefix>:link|label]] return label as plain-text
	[[<prefix>:link]] return <prefix>:link as plain-text

return value as is else

]=]

local function inter_wiki_check (parameter, value)
	local prefix = value:match ('%[%[(%a+):');									-- get an interwiki prefix if one exists
	local _;
	
	if prefix and cfg.inter_wiki_map[prefix:lower()] then						-- if prefix is in the map, needs preceding colon so
		table.insert( z.message_tail, {utilities.set_message ('err_bad_paramlink', parameter)});	-- emit an error message
		_, value, _ = utilities.is_wikilink (value);							-- extract label portion from wikilink
	end
	return value;
end


--[[--------------------------< M I S S I N G _ P I P E _ C H E C K >------------------------------------------

Look at the contents of a parameter. If the content has a string of characters and digits followed by an equal
sign, compare the alphanumeric string to the list of cs1|2 parameters.  If found, then the string is possibly a
parameter that is missing its pipe.  There are two tests made:
	{{cite ... |title=Title access-date=2016-03-17}}	-- the first parameter has a value and whitespace separates that value from the missing pipe parameter name
	{{cite ... |title=access-date=2016-03-17}}			-- the first parameter has no value (whitespace after the first = is trimmed by MediaWiki)
cs1|2 shares some parameter names with XML/HTML attributes: class=, title=, etc.  To prevent false positives XML/HTML
tags are removed before the search.

If a missing pipe is detected, this function adds the missing pipe maintenance category.

]]

local function missing_pipe_check (parameter, value)
	local capture;
	value = value:gsub ('%b<>', '');											-- remove XML/HTML tags because attributes: class=, title=, etc.

	capture = value:match ('%s+(%a[%w%-]+)%s*=') or value:match ('^(%a[%w%-]+)%s*=');	-- find and categorize parameters with possible missing pipes
	if capture and validate (capture) then										-- if the capture is a valid parameter name
		table.insert( z.message_tail, {utilities.set_message ('err_missing_pipe', parameter)});
	end
end


--[[--------------------------< H A S _ E X T R A N E O U S _ P U N C T >--------------------------------------

look for extraneous terminal punctuation in most parameter values; parameters listed in skip table are not checked

]]

local function has_extraneous_punc (param, value)
	if 'number' == type (param) then
		return;
	end
	
	param = param:gsub ('%d+', '#');											-- enumerated name-list mask params allow terminal punct; normalize 
	if cfg.punct_skip[param] then
		return;																	-- parameter name found in the skip table so done
	end
	
	if value:match ('[,;:]$') then
		utilities.set_message ('maint_extra_punct');							-- has extraneous punctuation; add maint cat
	end
end


--[[--------------------------< C I T A T I O N >--------------------------------------------------------------

This is used by templates such as {{cite book}} to create the actual citation text.

]]

local function citation(frame)
	Frame = frame;																-- save a copy in case we need to display an error message in preview mode
	local pframe = frame:getParent()
	local styles;
	
	if nil ~= string.find (frame:getTitle(), 'sandbox', 1, true) then			-- did the {{#invoke:}} use sandbox version?
		cfg = mw.loadData ('Module:Citation/CS1/Configuration/sandbox');		-- load sandbox versions of support modules
		whitelist = mw.loadData ('Module:Citation/CS1/Whitelist/sandbox');
		utilities = require ('Module:Citation/CS1/Utilities/sandbox');
		validation = require ('Module:Citation/CS1/Date_validation/sandbox');
		identifiers = require ('Module:Citation/CS1/Identifiers/sandbox');
		metadata = require ('Module:Citation/CS1/COinS/sandbox');
		styles = 'Module:Citation/CS1/sandbox/styles.css';
		
	else																		-- otherwise
		cfg = mw.loadData ('Module:Citation/CS1/Configuration');				-- load live versions of support modules
		whitelist = mw.loadData ('Module:Citation/CS1/Whitelist');
		utilities = require ('Module:Citation/CS1/Utilities');
		validation = require ('Module:Citation/CS1/Date_validation');
		identifiers = require ('Module:Citation/CS1/Identifiers');
		metadata = require ('Module:Citation/CS1/COinS');
		styles = 'Module:Citation/CS1/styles.css';
	end

	utilities.set_selected_modules (cfg);										-- so that functions in Utilities can see the selected cfg tables
	identifiers.set_selected_modules (cfg, utilities);							-- so that functions in Identifiers can see the selected cfg tables and selected Utilities module
	validation.set_selected_modules (cfg, utilities);							-- so that functions in Date validataion can see selected cfg tables and the selected Utilities module
	metadata.set_selected_modules (cfg, utilities);								-- so that functions in COinS can see the selected cfg tables and selected Utilities module

	z = utilities.z;															-- table of error and category tables in Module:Citation/CS1/Utilities

	local args = {};															-- table where we store all of the template's arguments
	local suggestions = {};														-- table where we store suggestions if we need to loadData them
	local error_text, error_state;

	local config = {};															-- table to store parameters from the module {{#invoke:}}
	for k, v in pairs( frame.args ) do											-- get parameters from the {{#invoke}} frame
		config[k] = v;
	--	args[k] = v;															-- crude debug support that allows us to render a citation from module {{#invoke:}}; skips parameter validation; TODO: keep?
	end	

	local capture;																-- the single supported capture when matching unknown parameters using patterns
	local empty_unknowns = {};													-- sequence table to hold empty unknown params for error message listing
	for k, v in pairs( pframe.args ) do											-- get parameters from the parent (template) frame
		v = mw.ustring.gsub (v, '^%s*(.-)%s*$', '%1');							-- trim leading/trailing whitespace; when v is only whitespace, becomes empty string
		if v ~= '' then
			if ('string' == type (k)) then
				k = mw.ustring.gsub (k, '%d', cfg.date_names.local_digits);		-- for enumerated parameters, translate 'local' digits to Western 0-9
			end
			if not validate( k, config.CitationClass ) then			
				error_text = "";
				if type( k ) ~= 'string' then
					-- exclude empty numbered parameters
					if v:match("%S+") ~= nil then
						error_text, error_state = utilities.set_message ( 'err_text_ignored', {v}, true );
					end
				elseif validate( k:lower(), config.CitationClass ) then 
					error_text, error_state = utilities.set_message ( 'err_parameter_ignored_suggest', {k, k:lower()}, true );	-- suggest the lowercase version of the parameter
				else
					if nil == suggestions.suggestions then						-- if this table is nil then we need to load it
						if nil ~= string.find (frame:getTitle(), 'sandbox', 1, true) then			-- did the {{#invoke:}} use sandbox version?
							suggestions = mw.loadData( 'Module:Citation/CS1/Suggestions/sandbox' );	-- use the sandbox version
						else
							suggestions = mw.loadData( 'Module:Citation/CS1/Suggestions' );			-- use the live version
						end
					end
					for pattern, param in pairs (suggestions.patterns) do		-- loop through the patterns to see if we can suggest a proper parameter
						capture = k:match (pattern);							-- the whole match if no capture in pattern else the capture if a match
						if capture then											-- if the pattern matches 
							param = utilities.substitute (param, capture);		-- add the capture to the suggested parameter (typically the enumerator)
							if validate (param, config.CitationClass) then		-- validate the suggestion to make sure that the suggestion is supported by this template (necessary for limited parameter lists)
								error_text, error_state = utilities.set_message ('err_parameter_ignored_suggest', {k, param}, true);	-- set the suggestion error message
							else
								error_text, error_state = utilities.set_message ( 'err_parameter_ignored', {k}, true );	-- suggested param not supported by this template
								v = '';											-- unset
							end
						end
					end
					if not utilities.is_set (error_text) then					-- couldn't match with a pattern, is there an explicit suggestion?						
						if (suggestions.suggestions[ k:lower() ] ~= nil) and validate (suggestions.suggestions[ k:lower() ], config.CitationClass) then
							error_text, error_state = utilities.set_message ( 'err_parameter_ignored_suggest', {k, suggestions.suggestions[ k:lower() ]}, true );
						else
							error_text, error_state = utilities.set_message ( 'err_parameter_ignored', {k}, true );
							v = '';												-- unset value assigned to unrecognized parameters (this for the limited parameter lists)
						end
					end
				end				  
				if error_text ~= '' then
					table.insert( z.message_tail, {error_text, error_state} );
				end				
			end

			args[k] = v;														-- save this parameter and its value

		elseif not utilities.is_set (v) then									-- for empty parameters
			if not validate (k, config.CitationClass, true) then				-- is this empty parameter a valid parameter
				k = ('' == k) and '(empty string)' or k;						-- when k is empty string (or was space(s) trimmed to empty string), replace with descriptive text
				table.insert (empty_unknowns, utilities.wrap_style ('parameter', k));	-- format for error message and add to the list
			end
																				-- crude debug support that allows us to render a citation from module {{#invoke:}} TODO: keep?
	--	elseif args[k] ~= nil or (k == 'postscript') then						-- when args[k] has a value from {{#invoke}} frame (we don't normally do that)
	--		args[k] = v;														-- overwrite args[k] with empty string from pframe.args[k] (template frame); v is empty string here
		end																		-- not sure about the postscript bit; that gets handled in parameter validation; historical artifact?
	end	

	if 0 ~= #empty_unknowns then												-- create empty unknown error message
		table.insert (z.message_tail, {utilities.set_message ('err_param_unknown_empty', {
			1 == #empty_unknowns and '' or 's',
			utilities.make_sep_list (#empty_unknowns, empty_unknowns)
			}, true )});
	end

	for k, v in pairs( args ) do
		if 'string' == type (k) then											-- don't evaluate positional parameters
			has_invisible_chars (k, v);											-- look for invisible characters
		end
		has_extraneous_punc (k, v);												-- look for extraneous terminal punctuation in parameter values
		missing_pipe_check (k, v);												-- do we think that there is a parameter that is missing a pipe?
		args[k] = inter_wiki_check (k, v);										-- when language interwiki-linked parameter missing leading colon replace with wiki-link label
	end

	return table.concat ({
		frame:extensionTag ('templatestyles', '', {src=styles}),
		citation0( config, args)
	});
end

--[[--------------------------< E X P O R T E D   F U N C T I O N S >------------------------------------------
]]

return {citation = citation};
    Retrieved from "https://nonbinary.wiki/index.php?title=Module:Citation/CS1&oldid=17821"