Module:Citation/CS1

    From Nonbinary Wiki
    Revision as of 13:20, 20 April 2019 by wikipedia>Trappist the monk (sync from sandbox;)

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

    
    --[[--------------------------< F O R W A R D   D E C L A R A T I O N S >--------------------------------------
    ]]
    
    local dates, year_date_check, reformat_dates, date_hyphen_to_dash,				-- functions in Module:Citation/CS1/Date_validation
    	date_name_xlate
    
    local is_set, in_array, substitute, error_comment, set_error, select_one,		-- functions in Module:Citation/CS1/Utilities
    	add_maint_cat, wrap_style, safe_for_italics, is_wikilink, make_wikilink;
    
    local z ={};																	-- tables in Module:Citation/CS1/Utilities
    
    local extract_ids, extract_id_access_levels, build_id_list, is_embargoed;		-- functions in Module:Citation/CS1/Identifiers
    
    local make_coins_title, get_coins_pages, COinS;									-- 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 >--------------------------------------
    
    delare variables here that have page-wide scope that are not brought in from other modules; thatare created here
    and used here
    
    ]]
    
    local added_deprecated_cat;														-- boolean flag so that the category is added only once
    local added_prop_cats = {};														-- list of property categories that have been added to z.properties_cats
    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 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 _ 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.
    
    foreign_lang_source and foreign_lang_source_2 keys have a language code appended to them so that multiple languages
    may be categorized but multiples of the same language are not categorized.
    
    added_prop_cats is a table declared in page scope variables above
    
    ]]
    
    local function add_prop_cat (key, arguments)
    	if not added_prop_cats [key] then
    		added_prop_cats [key] = true;											-- note that we've added this category
    		key = key:gsub ('(foreign_lang_source_?2?)%a%a%a?', '%1');				-- strip lang code from keyname
    		table.insert( z.properties_cats, substitute (cfg.prop_cats [key], arguments));		-- make name then add to table
    	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)
    	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', {source}, true ) } );
    	end
    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
    
    rfc952 (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 incase 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 ('^[%a%d]') 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
    																				-- Do most common case first
    	if domain:match ('%f[%a%d][%a%d][%a%d%-]+[%a%d]%.%a%a+$') then				-- three or more character hostname.hostname or hostname.tld
    		return true;
    	elseif domain:match ('%f[%a%d][%a%d][%a%d%-]+[%a%d]%.xn%-%-[%a%d]+$') then	-- internationalized domain name with ACE prefix
    		return true;
    	elseif domain:match ('%f[%a%d][%a%d]%.cash$') then							-- one character/digit .cash hostname
    		return true;
    	elseif domain:match ('%f[%a%d][%a%d]%.today') then							-- one character/digit .today hostname
    		return true;
    	elseif domain:match ('%f[%a%d][%a%d]%.org$') then							-- one character/digit .org hostname
    		return true;
    	elseif domain:match ('%f[%a][qxz]%.com$') then								-- assigned one character .com hostname (x.com times out 2015-12-10)
    		return true;
    	elseif domain:match ('%f[%a][iq]%.net$') then								-- assigned one character .net hostname (q.net registered but not active 2015-12-10)
    		return true;
    	elseif domain:match ('%f[%a%d][%a%d]%.%a%a$') then							-- one character hostname and cctld (2 chars)
    		return true;
    	elseif domain:match ('%f[%a%d][%a%d][%a%d]%.%a%a+$') then					-- two character hostname and tld
    		return true;
    	elseif domain:match ('^%d%d?%d?%.%d%d?%d?%.%d%d?%d?%.%d%d?%d?') then		-- IPv4 address
    		return true;
    	else
    		return false;
    	end
    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 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.
    
    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
    		authority = authority:gsub ('//', '', 1);								-- replace place 1 pair of '/' with nothing;
    		if 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
    		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 wikilinked but not when |<param>-link= has a value.  This function emits an error message when
    that condition exists
    
    ]]
    
    local function link_title_ok (link, lorig, title, torig)
    local orig;
    
    	if 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
    		end
    	end
    
    	if is_set (orig) then
    		table.insert( z.message_tail, { set_error( 'bad_paramlink', orig)});	-- url or wikilink in |title= with |title-link=;
    	end
    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 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 is_set (error_message) then												-- done looping, if there is an error message, display it
    		table.insert( z.message_tail, { set_error( '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, { set_error( '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 is_set( label ) then
    		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
    	if not check_url( URL ) then
    		error_str = set_error( 'bad_url', {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 wikimarkup url
    
    	if is_set (access) then														-- access level (subscription, registration, limited)
    		base_url = 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, { set_error( 'deprecated_params', {name}, true ) } );		-- add error 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 wikimarkup) are not kerned.
    
    Replaces unicode quotemarks 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 = 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 = substitute (cfg.presentation['kern-wl-both'], str);
    		elseif mw.ustring.match (str, '%[%[[\"“”\'‘’].+%]%]')	then			-- leading quote marks
    			str = substitute (cfg.presentation['kern-wl-left'], str);
    		elseif mw.ustring.match (str, '%[%[.+[\"“”\'‘’]%]%]') then				-- trailing quote marks
    			str = 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 is_set (cap) then
    			label = 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 is_set (cap) then
    			label = substitute (cfg.presentation['kern-right'], {cap, cap2});
    		end
    		
    		if 2 == wl_type then
    			str = 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 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
    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=
    
    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 lang='';																-- initialize to empty string
    	local name;
    	if script_value:match('^%l%l%s*:') then										-- if first 3 non-space characters are script language prefix
    		lang = script_value:match('^(%l%l)%s*:%s*%S.*');						-- get the language prefix or nil if there is no script
    		if not is_set (lang) then
    			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, "en" );	-- get language name so that we can use it to categorize
    		if is_set (name) then													-- is prefix a proper ISO 639-1 language code?
    			script_value = script_value:gsub ('^%l%l%s*:%s*', '');				-- strip prefix from script
    																				-- is prefix one of these language codes?
    			if in_array (lang, cfg.script_lang_codes) then
    				add_prop_cat ('script_with_name', {name, lang})
    			else
    				add_prop_cat ('script')
    			end
    			lang = ' lang="' .. lang .. '" ';									-- convert prefix into a lang attribute
    		else
    			lang = '';															-- invalid so set lang to empty string
    		end
    	end
    	script_value = 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)
    	if is_set (script) then
    		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
    	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 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 substitute( msg, str );										-- including template text
    	else
    		return 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;
    
    	wl_type, D, L = 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 is_set (str) then
    			ws_url = table.concat ({											-- build a wikisource url
    				'https://en.wikisource.org/wiki/',								-- 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 is_set (str) then
    			ws_url = table.concat ({											-- build a wikisource url
    				'https://en.wikisource.org/wiki/',								-- 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 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
    				'https://en.wikisource.org/wiki/',								-- 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 anchor
    	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 _ 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 (scriptchapter, chapter, transchapter, chapterurl, 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 separaters with space characters
    		chapter = ws_label;
    	end
    
    	if not 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 = wrap_style ('quoted-title', chapter);
    		end
    	end
    
    	chapter = script_concatenate (chapter, scriptchapter)						-- <bdi> tags, lang atribute, categorization, etc; must be done after title is wrapped
    
    	if is_set (chapterurl) then
    		chapter = external_link (chapterurl, 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 = substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, chapter});				
    	end
    
    	if is_set (transchapter) then
    		transchapter = wrap_style ('trans-quoted-title', transchapter);
    		if is_set (chapter) then
    			chapter = chapter ..  ' ' .. transchapter;
    		else																	-- here when transchapter without chapter or script-chapter
    			chapter = transchapter;												-- 
    			chapter_error = ' ' .. set_error ('trans_missing_title', {'chapter'});
    		end
    	end
    
    --	if is_set (chapterurl) then
    --		chapter = external_link (chapterurl, chapter, chapter_url_source, access);		-- adds bare_url_missing_title error if appropriate
    --	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 nonprintable 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 dummy;																-- end of matching string; not used but required to hold end position when a capture is returned
    	local capture;																-- used by stripmarker detection to hold name of the stripmarker
    	local i=1;
    	local stripmarker, apostrophe;
    	
    	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
    
    	while cfg.invisible_chars[i] do
    		local char=cfg.invisible_chars[i][1]									-- the character or group name
    		local pattern=cfg.invisible_chars[i][2]									-- the pattern used to find it
    		position, dummy, capture = mw.ustring.find (v, pattern)					-- see if the parameter value contains characters that match the pattern
    		
    		if position and (char == 'zero width joiner') then						-- if we found a zero width joiner character
    			if mw.ustring.find (v, cfg.indic_script) then						-- its ok if one of the indic scripts
    				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 in_array (param, {'id', 'quote'})) then	-- templatestyles stripmarker allowed in these parameters
    					stripmarker = true;											-- set a flag
    			elseif true == stripmarker and 'delete' == char 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 then
    					err_msg = capture .. ' ' .. char;
    				else
    					err_msg = char .. ' ' .. 'character';
    				end
    
    				table.insert( z.message_tail, { set_error( 'invisible_char', {err_msg, wrap_style ('parameter', param), position}, true ) } );	-- add error message
    				return;															-- and done with this parameter
    			end
    		end
    		i=i+1;																	-- bump our index
    	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] = 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
    
    
    --[[--------------------------< 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 = 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 = 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 is_set(title_type) then
    		if "none" == 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 is_set (str) then
    		return str;
    	end
    	
    	str, count = str:gsub ('^%(%((.+)%)%)$', '%1');								-- remove accept-this-as-written markup when it wraps all of str
    	if 0 ~= count then															-- non-zero when markup removed; zero else
    		return str;																-- nothing to do, we're done
    	end
    	
    	str = str:gsub ('&[nm]dash;', {['&ndash;'] = '–', ['&mdash;'] = '—'});		-- replace &mdash; and &ndash; entities  with their characters; semicolon mucks up the text.split
    	
    	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
    		if mw.ustring.match (item, '^%w*[%.%-]?%w+%s*[%-–—]%s*%w*[%.%-]?%w+$') then	-- if a hyphenated range or has endash or emdash separators
    			if item:match ('%a+[%.%-]?%d+%s*%-%s*%a+[%.%-]?%d+') or				-- letterdigit hyphen letterdigit (optional separator between letter and digit)
    				item:match ('%d+[%.%-]?%a+%s*%-%s*%d+[%.%-]?%a+') or			-- digitletter hyphen digitletter (optional separator between digit and letter)
    				item:match ('%d+[%.%-]%d+%s*%-%s*%d+[%.%-]%d+') or				-- digit separator digit hyphen digit separator digit
    				item:match ('%d+%s*%-%s*%d+') or								-- digit hyphen digit
    				item:match ('%a+%s*%-%s*%a+') then								-- letter hyphen letter
    					item = item:gsub ('(%w*[%.%-]?%w+)%s*%-%s*(%w*[%.%-]?%w+)', '%1–%2');	-- replace hyphen, remove extraneous space characters
    			else
    				item = mw.ustring.gsub (item, '%s*[–—]%s*', '–');				-- for endash or emdash separated ranges, replace em with en, remove extraneous white space
    			end
    		end
    		item = item:gsub ('^%(%((.+)%)%)$', '%1');								-- remove the accept-this-as-written markup
    		table.insert (out, item);												-- add the (possibly modified) item to the output table
    	end
    
    	return table.concat (out, ', ');											-- concatenate the output table into a comma separated string
    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 'dupicate 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 wikimarkup
    					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 wikimarkup
    					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 2–9.  Puncutation not allowed.
    
    ]]
    
    local function is_suffix (suffix)
    	if in_array (suffix, {'Jr', 'Sr', '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 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
    	[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 ouside 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)
    	local first, suffix = first:match ('(.-),?%s*([%dJS][%drndth]+)%.?$') or first;		-- if first has something that looks like a generational suffix, get it
    
    	if is_set (suffix) then
    		if not is_suffix (suffix) then
    			add_vanc_error ('suffix');
    			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 ('non-Latin character');
    			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-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/.
    
    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)
    	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 intials?
    	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 ('suffix');									-- 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 intial 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 (e.g. authors / editors) 
    
    ]]
    
    local function list_people(control, people, etal)
    	local sep;
    	local namesep;
    	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 = cfg.presentation['sep_nl_vanc'];									-- name-list separator between authors 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 authors 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 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 = make_wikilink (person.link, one);						-- link author/editor if this page is not the author's/editor's page
    				end
    			end
    			table.insert( text, one )
    			table.insert( text, sep_one )
    		end
    	end
    
    	local count = #text / 2;													-- (number of names + number of separators) divided by 2
    	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
    
    
    --[[--------------------------< 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.
    
    namelist is one of the contributor-, author-, or editor-name lists chosen in that order.  year is Year or anchor_year.
    
    ]]
    local function anchor_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 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 it's 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 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, {set_error ('etal', {param})});		-- and set an error if not added
    				end
    			end
    		end
    	end
    
    	return name, etal;															-- 
    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 extranious editor annotations: ed, ed., eds, (Ed.), etc.
    These annotation do not belong in author parameters and are redundant in editor parameters.  If found, the function
    adds the editor markup maintenance category.
    
    ]]
    
    local function name_has_ed_markup (name, list_name)
    	local _, pattern;
    	local patterns = cfg.editor_markup_patterns;								-- get patterns from configuration
    
    	if is_set (name) then
    		for _, pattern in ipairs (patterns) do									-- spin through patterns table and
    			if name:match (pattern) then
    				add_maint_cat ('extra_text_names', cfg.special_case_translation [list_name]);	-- add a maint cat for this template
    				break;
    			end
    		end
    	end
    	return name;																-- and done
    end
    
    
    --[[--------------------------< N A M E _ H A S _ M U L T _ N A M E S >----------------------------------------
    
    Evaluates the content of author and editor (surnames only) parameters for multiple names.  Multiple names are
    indicated if there is more than one comma and or semicolon.  If found, the function adds the multiple name
    (author or editor) maintenance category.
    
    ]]
    
    local function name_has_mult_names (name, list_name)
    local count, _;
    	if is_set (name) then
    		_, count = name:gsub ('[;,]', '');										-- count the number of separator-like characters
    		
    		if 1 < count then														-- param could be |author= or |editor= so one separator character is acceptable
    			add_maint_cat ('mult_names', cfg.special_case_translation [list_name]);	-- more than one separator indicates multiple names so add a maint cat for this template
    		end
    	end
    	return name;																-- and done
    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)
    	if is_set (last) then
    		if last:match ('^%(%(.*%)%)$') then										-- if wrapped in doubled parentheses, accept as written 
    			last = last:match ('^%(%((.*)%)%)$');								-- strip parens
    		else
    			last = name_has_mult_names (last, list_name);						-- check for multiple names in the parameter (last only)
    			last = name_has_ed_markup (last, list_name);						-- check for extraneous 'editor' annotation
    		end
    	end
    	if is_set (first) then
    		if first:match ('^%(%(.*%)%)$') then									-- if wrapped in doubled parentheses, accept as written 
    			first = first:match ('^%(%((.*)%)%)$');								-- strip parens
    		else
    			first = name_has_ed_markup (first, list_name);						-- check for extraneous 'editor' annotation
    		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, the page is added to a maintenance category.
    
    ]]
    
    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;												-- selected parameter aliases used in error messaging
    	while true do
    		last, last_alias = select_one( args, cfg.aliases[list_name .. '-Last'], 'redundant_parameters', i );		-- search through args for name components beginning at 1
    		first, first_alias = 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, 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
    			table.insert( z.message_tail, { set_error( 'first_missing_last', {first_alias, first_alias:gsub('first', 'last')}, 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
    			link_title_ok (link, list_name:match ("(%w+)List"):lower() .. '-link' .. i, last, list_name:match ("(%w+)List"):lower() .. '-last' .. i);	-- check for improper wikimarkup
    
    			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', {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
    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 languages = mw.language.fetchLanguageNames(this_wiki_code, 'all')		-- get a list of language names known to Wikimedia
    																				-- ('all' is required for North Ndebele, South Ndebele, and Ojibwa)
    	local langlc = mw.ustring.lower(lang);										-- lower case version for comparisons
    
    	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() or 3 == code:len() then							-- two- or three-character codes only; 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 bit 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.
    
    ]]
    
    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 = mw.getContentLanguage();									-- get a language object for this wiki
    	local this_wiki_code = this_wiki:getCode()									-- get this wiki's language code
    	local this_wiki_name = mw.language.fetchLanguageName(this_wiki_code, 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
    			lang = lang:gsub ('^(%a%a%a?)%-.*', '%1');							-- strip ietf tags from code
    		else
    			if lang:match ('^%a%a%-') then										-- strip ietf tags from code; TODO: is there a need to support 3-char with tag?
    				lang = lang:match ('(%a%a)%-')									-- keep only 639-1 code portion to lang; TODO: do something with 3166 alpha 2 country code?
    			end
    			if 2 == lang:len() or 3 == lang:len() then							-- if two-or three-character code
    				name = mw.language.fetchLanguageName (lang:lower(), this_wiki_code);	-- get language name if |language= is a proper code
    			end
    		end
    
    		if is_set (name) then													-- if |language= specified a valid code
    			code = lang:lower();												-- save it
    		else
    			name, code = get_iso639_code (lang, this_wiki_code);				-- attempt to get code from name (assign name here so that we are sure of proper capitalization)
    		end
    	
    		if 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 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
    					add_prop_cat ('foreign_lang_source' .. code, {name, code})	-- categorize it
    				else															-- or is a recognized language (but has a three-character code)
    					add_prop_cat ('foreign_lang_source_2' .. code, {code})		-- categorize it differently TODO: support mutliple three-character code categories per cs1|2 template
    				end
    			end
    		else
    			add_maint_cat ('unknown_lang');										-- add maint category if not already added
    		end
    		
    		table.insert (language_list, name);
    		name = '';																-- so we can reuse it
    	end
    	
    	code = #language_list														-- reuse code as number of languages in the list
    	if 2 >= code then
    		name = table.concat (language_list, cfg.messages['parameter-pair-separator'])		-- insert '<space>and<space>' between two language names
    	elseif 2 < code then
    		name = table.concat (language_list, ', ');											-- and concatenate with '<comma><space>' separators
    		name = name:gsub (', ([^,]+)$', cfg.messages['parameter-final-separator'] .. '%1');	-- replace last '<comma><space>' separator with '<comma><space>and<space>' separator
    	end
    	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 1 _ S T Y L E >----------------------------------------------------
    
    Set style settings for CS1 citation templates. Returns separator and postscript settings
    At en.wiki, for cs1:
    	ps gets:	'.'
    	sep gets:	'.'
    
    ]]
    
    local function set_cs1_style (ps)
    	if not is_set (ps) then														-- unless explicitely set to something
    		ps = cfg.presentation['ps_cs1'];										-- terminate the rendered citation
    	end
    	return cfg.presentation['sep_cs1'], ps;										-- element separator
    end
    
    
    --[[--------------------------< S E T _ C S 2 _ S T Y L E >----------------------------------------------------
    
    Set style settings for CS2 citation templates. Returns separator, postscript, ref settings
    At en.wiki, for cs2:
    	ps gets:	'' (empty string - no terminal punctuation)
    	sep gets:	','
    
    ]]
    
    local function set_cs2_style (ps, ref)
    	if not is_set (ps) then														-- if |postscript= has not been set, set cs2 default
    		ps = cfg.presentation['ps_cs2'];										-- terminate the rendered citation
    	end
    	if not is_set (ref) then													-- if |ref= is not set
    		ref = "harv";															-- set default |ref=harv
    	end
    	return cfg.presentation['sep_cs2'], ps, ref;								-- element separator
    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;
    	if (cite_class == "citation") then											-- for citation templates (CS2)
    		sep, ps, ref = set_cs2_style (ps, ref);
    	else																		-- not a citation template so CS1
    		sep, ps = set_cs1_style (ps);
    	end
    
    	return sep, ps, ref															-- return them all
    end
    
    
    --[[--------------------------< S E T _ S T Y L E >------------------------------------------------------------
    
    Establish basic style settings to be used when rendering the citation.  Uses |mode= if set and valid or uses
    config.CitationClass from the template's #invoke: to establish style.
    
    ]]
    
    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
    	
    	return sep, ps, ref
    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 is_set (format) then
    		format = wrap_style ('format', format);									-- add leading space, parentheses, resize
    		if not is_set (url) then
    			format = format .. set_error( '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 = 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)
    	if 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
    				add_maint_cat ('disp_name', cfg.special_case_translation [list_name]);
    			end
    		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
    			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 page to Category:CS1 maint: extra text if |page= or |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:
    	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
    	bad pattern: '^[Pp][Pp]' matches matches when |page(s)= begins pp or pP or Pp or PP
    
    ]]
    
    local function extra_text_in_page_check (page)
    	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?
    	local bad_pattern = '^[Pp]?[Pp]%.?[ %d]';
    
    	if not page:match (good_pattern) and (page:match (bad_pattern) or  page:match ('^[Pp]ages?')) then
    		add_maint_cat ('extra_text');
    	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 parnetheses 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 place holder
    	
    	local i = 1;
    	
    	while name_table[i] do
    		if name_table[i]:match ('^%(%(.*[^%)][^%)]$') then						-- first segment of corporate with one or more commas; this segment has the opening doubled parens
    			local name = name_table[i];
    			i=i+1;																-- bump indexer to next segment
    			while name_table[i] do
    				name = name .. ', ' .. name_table[i];							-- concatenate with previous segments
    				if name_table[i]:match ('^.*%)%)$') then						-- if this table member has the closing doubled parens
    					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 = 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 paranethese ((corporate name)) to suppress the format tests.
    
    Supports generational suffixes Jr, 2nd, 3rd, 4th–6th.
    
    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 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
    		if v_name:match ('^%(%(.+%)%)$') then									-- corporate authors are wrapped in doubled parentheses to supress vanc formatting and error detection
    			first = '';															-- set to empty string for concatenation and because it may have been set for previous author/editor
    			last = v_name:match ('^%(%((.+)%)%)$')								-- remove doubled parntheses
    			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 ('punctuation');
    			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 author intials
    			if is_suffix (first) then											-- if a valid suffix
    				suffix = first													-- save it as a suffix and
    				first = table.remove(lastfirstTable);							-- get what should be the initials from the table
    			end																	-- no suffix error message here because letter combination may be result of Romanization; check for digits?
    			last = table.concat(lastfirstTable, " ")							-- returns a string that is the concatenation of all other names that are not initials
    			if mw.ustring.match (last, '%a+%s+%u+%s+%a+') then
    				add_vanc_error ('missing comma');								-- 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 ('name');										-- matches a space between two intiials
    			end
    		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?
    		end
    																
    		if 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 ('initials');									-- too many initials; mixed case initials (which may be ok Romanization); hyphenated initials
    			end
    			is_good_vanc_name (last, first);									-- check first and last before restoring the suffix which may have a non-Latin digit
    			if 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, '');
    			end
    		end
    
    		link = select_one( args, cfg.aliases[list_name .. '-Link'], 'redundant_parameters', i ) or v_link_table[i];
    		mask = select_one( args, cfg.aliases[list_name .. '-Mask'], '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 |editors=, |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
    similarly, |editorn= (and aliases) highest and |editors= lowest
    
    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 or editors as appropriate.
    
    ]]
    
    local function select_author_editor_source (vxxxxors, xxxxors, args, list_name)
    local lastfirst = false;
    	if select_one( args, cfg.aliases[list_name .. '-Last'], 'none', 1 ) or		-- do this twice incase we have a |first1= without a |last1=; this ...
    		select_one( args, cfg.aliases[list_name .. '-First'], 'none', 1 ) or	-- ... also catches the case where |first= is used with |vauthors=
    		select_one( args, cfg.aliases[list_name .. '-Last'], 'none', 2 ) or
    		select_one( args, cfg.aliases[list_name .. '-First'], 'none', 2 ) then
    			lastfirst=true;
    	end
    
    	if (is_set (vxxxxors) and true == lastfirst) or								-- these are the three error conditions
    		(is_set (vxxxxors) and is_set (xxxxors)) or
    		(true == lastfirst and 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, { set_error( '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 is_set (vxxxxors) then return 2 end;
    	if 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, no, etc).  When the parameter value has not been assigned a value (missing or empty
    in the source template) the function returns true.  If the parameter value is one of the list of allowed values returns
    true; else, emits an error message and returns false.
    
    ]]
    
    local function is_valid_parameter_value (value, name, possible)
    	if not is_set (value) then
    		return true;															-- an empty parameter is ok
    	elseif in_array(value:lower(), possible) then
    		return true;
    	else
    		table.insert( z.message_tail, { set_error( 'invalid_param_val', {name, value}, true ) } );	-- not an allowed value so add error message
    		return false
    	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 terninate 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 is_set (volume) and not is_set (issue) then
    		return '';
    	end
    	
    	if 'magazine' == cite_class or (in_array (cite_class, {'citation', 'map'}) and 'magazine' == origin) then
    		if is_set (volume) and is_set (issue) then
    			return wrap_msg ('vol-no', {sepc, volume, issue}, lower);
    		elseif is_set (volume) then
    			return wrap_msg ('vol', {sepc, volume}, lower);
    		else
    			return wrap_msg ('issue', {sepc, issue}, lower);
    		end
    	end
    
    	local vol = '';																-- here for all cites except magazine
    		
    	if is_set (volume) then
    		if volume:match ('^[MDCLXVI]+$') or volume:match ('^%d+$')then			-- volume value is all digits or all uppercase roman numerals
    			vol = substitute (cfg.presentation['vol-bold'], {sepc, hyphen_to_dash(volume)});	-- render in bold face
    		elseif (4 < mw.ustring.len(volume)) then								-- not all digits or roman numerals and longer than 4 characters
    			vol = substitute (cfg.messages['j-vol'], {sepc, volume});			-- not bold
    			add_prop_cat ('long_vol');
    		else																	-- four or less characters
    			vol = substitute (cfg.presentation['vol-bold'], {sepc, hyphen_to_dash(volume)});	-- bold
    		end
    	end
    	if is_set (issue) then
    		return vol .. 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 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 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 (in_array (cite_class, {'citation', 'map', 'interview'}) and 'journal' == origin);
    	
    	if is_set (page) then
    		if is_journal then
    			return substitute (cfg.messages['j-page(s)'], page), '', '', '';
    		elseif not nopp then
    			return substitute (cfg.messages['p-prefix'], {sepc, page}), '', '', '';
    		else
    			return substitute (cfg.messages['nopp'], {sepc, page}), '', '', '';
    		end
    	elseif is_set(pages) then
    		if is_journal then
    			return 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 '', substitute (cfg.messages['p-prefix'], {sepc, pages}), '', '';
    		elseif not nopp then
    			return '', substitute (cfg.messages['pp-prefix'], {sepc, pages}), '', '';
    		else
    			return '', 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 interwikilink as plain text
    for use in COinS.  This COinS thing is done because here we convert an interwiki link to and 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, pages, at)
    	local ws_url, ws_label, coins_pages, L;										-- for wikisource interwikilinks; TODO: this corrupts page metadata (span remains in place after cleanup; fix there?)
    
    	if is_set (page) then
    		if is_set (pages) or is_set(at) then
    			pages = '';															-- unset the others
    			at = '';
    		end
    		extra_text_in_page_check (page);										-- add this page to maint cat if |page= value begins with what looks like p. or pp.
    
    		ws_url, ws_label, L = wikisource_url_make (page);						-- make ws url from |page= interwiki link; link portion L becomes tool tip 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 = substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, page});
    			coins_pages = ws_label;
    		end
    	elseif is_set (pages) then
    		if is_set (at) then
    			at = '';															-- unset
    		end
    		extra_text_in_page_check (pages);										-- add this page to maint cat if |pages= value begins with what looks like p. or pp.
    
    		ws_url, ws_label, L = wikisource_url_make (pages);						-- make ws url from |pages= interwiki link; link portion L becomes tool tip 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 = substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, pages});
    			coins_pages = ws_label;
    		end
    	elseif is_set (at) then
    		ws_url, ws_label, L = wikisource_url_make (at);							-- make ws url from |at= interwiki link; link portion L becomes tool tip 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 = substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], L, at});
    			coins_pages = ws_label;
    		end
    	end
    	
    	return page, pages, at, coins_pages;
    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 funct 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.or 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 = 'save command';
    		url = url:gsub ('(//web%.archive%.org)/save/', '%1/*/', 1);				-- for preview mode: modify ArchiveURL
    	elseif url:match('//liveweb%.archive%.org/') then
    		err_msg = 'liveweb';
    	else
    		path, timestamp, flag = url:match('//web%.archive%.org/([^%d]*)(%d+)([^/]*)/');		-- split out some of the url parts for evaluation
    		
    		if not is_set(timestamp) or 14 ~= timestamp:len() then					-- path and flag optional, must have 14-digit timestamp here
    			err_msg = '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 is_set(path) and 'web/' ~= path then								-- older archive urls do not have the extra 'web/' path element
    			err_msg = 'path';
    		elseif is_set (flag) and not is_set (path) then							-- flag not allowed with the old form url (without the 'web/' path element)
    			err_msg = 'flag';
    		elseif 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 = 'flag';
    		else
    			return url, date;													-- return archiveURL and ArchiveDate
    		end
    	end
    																				-- if here, something not right so
    	table.insert( z.message_tail, { set_error( 'archive_url', {err_msg}, true ) } );	-- add error message and
    	if 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
    
    
    --[[--------------------------< 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.	
    
    -- set default parameter values defined by |mode= parameter.
    	local Mode = A['Mode'];
    	if not is_valid_parameter_value (Mode, 'mode', cfg.keywords['mode']) then
    		Mode = '';
    	end
    
    	local author_etal;
    	local a	= {};																-- authors list from |lastn= / |firstn= pairs or |vauthors=
    	local Authors;
    	local NameListFormat = A['NameListFormat'];
    	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
    			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=
    			if 'authors' == A:ORIGIN('Authors') then							-- but add a maint cat if the parameter is |authors=
    				add_maint_cat ('authors');										-- because use of this parameter is discouraged; what to do about the aliases is a TODO:
    			end
    		end
    		if is_set (Collaboration) then
    			author_etal = true;													-- so that |display-authors=etal not required
    		end
    	end
    
    	local Others = A['Others'];
    
    	local editor_etal;
    	local e	= {};																-- editors list from |editor-lastn= / |editor-firstn= pairs or |veditors=
    	local Editors;
    
    	do																			-- to limit scope of selected
    		local selected = select_author_editor_source (A['Veditors'], A['Editors'], args, 'EditorList');
    		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
    			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=
    			add_maint_cat ('editors');											-- but add a maint cat because use of this parameter is discouraged
    		end
    	end
    
    	local translator_etal;
    	local t = {};																-- translators list from |translator-lastn= / translator-firstn= pairs
    	local Translators;															-- assembled translators name list
    	t = extract_names (args, 'TranslatorList');									-- fetch translator list from |translatorn= / |translator-lastn=, -firstn=, -linkn=, -maskn=
    
    	local interviewer_etal;
    	local interviewers_list = {};												
    	local Interviewers;															-- used later
    	interviewers_list = extract_names (args, 'InterviewerList');				-- process preferred interviewers parameters
    
    	local contributor_etal;
    	local c = {};																-- contributors list from |contributor-lastn= / contributor-firstn= pairs
    	local Contributors;															-- assembled contributors name list
    	local Contribution = A['Contribution'];
    	if in_array(config.CitationClass, {"book","citation"}) and not 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 is_set (Contribution) then									-- |contributor= requires |contribution=
    				table.insert( z.message_tail, { set_error( '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, { set_error( '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 select_one (args, cfg.aliases['ContributorList-Last'], 'redundant_parameters', 1 ) then	-- are there contributor name list parameters?
    			table.insert( z.message_tail, { set_error( 'contributor_ignored')});	-- add contributor ignored error message
    		end
    		Contribution = nil;														-- unset
    	end
    
    	if not is_valid_parameter_value (NameListFormat, 'name-list-format', cfg.keywords['name-list-format']) then			-- only accepted value for this parameter is 'vanc'
    		NameListFormat = '';													-- anything else, set to empty string
    	end
    
    if is_set (Others) then
    	if 0 == #a and 0 == #e then									-- add maint cat when |others= has value and used without |author=, |editor=
    		add_maint_cat ('others');
    	end
    end
    
    	local Year = A['Year'];
    	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'];
    			link_title_ok (TitleLink, A:ORIGIN ('TitleLink'), Title, 'title');	-- check for wikimarkup in |title-link= or wikimarkup in |title= when |title-link= is set
    
    	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 ArchiveDate;
    	local ArchiveURL;
    
    	ArchiveURL, ArchiveDate = archive_url_check (A['ArchiveURL'], A['ArchiveDate'])
    	
    	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 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 Periodical_origin = A:ORIGIN('Periodical');							-- get the name of the periodical parameter
    
    	local Series = A['Series'];
    	
    	local Volume;
    	local Issue;
    	local Page;
    	local Pages;
    	local At;
    
    	if in_array (config.CitationClass, cfg.templates_using_volume) then
    		Volume = A['Volume'];
    	end
    																				-- conference & map books do not support issue
    	if in_array (config.CitationClass, cfg.templates_using_issue) and not (in_array (config.CitationClass, {'conference', 'map'}) and not is_set (Periodical))then
    		Issue = hyphen_to_dash (A['Issue']);
    	end
    	local Position = '';
    	if not 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 = A['PublicationPlace']
    	local Place = A['Place'];
    	
    	local PublisherName = A['PublisherName'];
    	local RegistrationRequired = A['RegistrationRequired'];
    		if not is_valid_parameter_value (RegistrationRequired, 'registration', cfg.keywords ['yes_true_y']) then
    			RegistrationRequired=nil;
    		end
    
    	local SubscriptionRequired = A['SubscriptionRequired'];
    		if not is_valid_parameter_value (SubscriptionRequired, 'subscription', cfg.keywords ['yes_true_y']) then
    			SubscriptionRequired=nil;
    		end
    
    	local UrlAccess = A['UrlAccess'];
    		if not is_valid_parameter_value (UrlAccess, 'url-access', cfg.keywords ['url-access']) then
    			UrlAccess = nil;
    		end
    		if not is_set(URL) and is_set(UrlAccess) then
    			UrlAccess = nil;
    			table.insert( z.message_tail, { set_error( 'param_access_requires_param', {'url'}, true ) } );
    		end
    
    		if is_set (UrlAccess) and is_set (SubscriptionRequired) then			-- while not aliases, these are much the same so if both are set
    			table.insert( z.message_tail, { set_error( 'redundant_parameters', {wrap_style ('parameter', 'url-access') .. ' and ' .. wrap_style ('parameter', 'subscription')}, true ) } );		-- add error message
    			SubscriptionRequired = nil;											-- unset; prefer |access= over |subscription=
    		end
    		if is_set (UrlAccess) and is_set (RegistrationRequired) then			-- these are not the same but contradictory so if both are set
    			table.insert( z.message_tail, { set_error( 'redundant_parameters', {wrap_style ('parameter', 'url-access') .. ' and ' .. wrap_style ('parameter', 'registration')}, true ) } );		-- add error message
    			RegistrationRequired = nil;											-- unset; prefer |access= over |registration=
    		end
    
    	local ChapterUrlAccess = A['ChapterUrlAccess'];
    		if not is_valid_parameter_value (ChapterUrlAccess, 'chapter-url-access', cfg.keywords ['url-access']) then	-- same as url-access
    			ChapterUrlAccess = nil;
    		end
    		if not is_set(ChapterURL) and is_set(ChapterUrlAccess) then
    			ChapterUrlAccess = nil;
    			table.insert( z.message_tail, { set_error( 'param_access_requires_param', {'chapter-url'}, true ) } );
    		end
    
    	local Via = A['Via'];
    	local AccessDate = A['AccessDate'];
    	local Agency = A['Agency'];
    
    	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 );
    	local ID_access_levels = extract_id_access_levels( args, ID_list );
    
    	local Quote = A['Quote'];
    
    	local LayFormat = A['LayFormat'];
    	local LayURL = A['LayURL'];
    	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'];
    		if not is_valid_parameter_value (LastAuthorAmp, 'last-author-amp', cfg.keywords ['yes_true_y']) then
    			LastAuthorAmp = nil;												-- set to empty string
    		end
    
    	local no_tracking_cats = A['NoTracking'];
    		if not is_valid_parameter_value (no_tracking_cats, 'no-tracking', cfg.keywords ['yes_true_y']) then
    			no_tracking_cats = nil;												-- set to empty string
    		end
    
    	--local variables that are not cs1 parameters
    	local use_lowercase;														-- controls capitalization of certain static text
    	local this_page = mw.title.getCurrentTitle();								-- also used for COinS and for language
    	local anchor_year;															-- used in the CITEREF identifier
    	local COinS_date = {};														-- holds date info extracted from |date= for the COinS metadata by Module:Date verification
    
    	local DF = A['DF'];															-- date format set in cs1|2 template
    	if not is_valid_parameter_value (DF, 'df', cfg.keywords['date-format']) then	-- validate reformatting keyword
    		DF = '';																-- not valid, set to empty string
    	end
    	if not is_set (DF) then
    		DF = cfg.global_df;
    	end
    
    	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
    			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)
    	select_one( args, {'page', 'p', 'pp', 'pages', 'at', 'sheet', 'sheets'}, '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, Pages, At);
    
    	local NoPP = A['NoPP'] 
    	if is_set (NoPP) and is_valid_parameter_value (NoPP, 'nopp', cfg.keywords ['yes_true_y']) then
    		NoPP = true;
    	else
    		NoPP = nil;																-- unset, used as a flag later
    	end
    
    	-- both |publication-place= and |place= (|location=) allowed if different
    	if not is_set(PublicationPlace) and is_set(Place) then
    		PublicationPlace = Place;							-- promote |place= (|location=) to |publication-place
    	end
    	
    	if PublicationPlace == Place then Place = ''; end		-- don't need both if they are the same
    	
    	--[[
    	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
    		|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
    	
    	]]
    
    local Encyclopedia = A['Encyclopedia'];
    
    	if ( config.CitationClass == "encyclopaedia" ) or ( config.CitationClass == "citation" and is_set (Encyclopedia)) then	-- test code for citation
    		if is_set(Periodical) then												-- Periodical is set when |encyclopedia is set
    			if is_set(Title) or is_set (ScriptTitle) then
    				if not is_set(Chapter) then
    					Chapter = Title;											-- |encyclopedia and |title are set so map |title to |article and |encyclopedia to |title
    					ScriptChapter = ScriptTitle;
    					TransChapter = TransTitle;
    					ChapterURL = URL;
    					ChapterUrlAccess = UrlAccess;
    
    					if not is_set (ChapterURL) and is_set (TitleLink) then
    						Chapter = make_wikilink (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
    
    	-- Special case for cite techreport.
    	if (config.CitationClass == "techreport") then								-- special case for cite techreport
    		if is_set(A['Number']) then												-- cite techreport uses 'number', which other citations alias to 'issue'
    			if not 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, { set_error('redundant_parameters', {wrap_style ('parameter', 'id') .. ' and ' .. wrap_style ('parameter', 'number')}, true )});
    			end
    		end	
    	end
    
    	-- special case for cite mailing list
    	if (config.CitationClass == "mailinglist") then
    		Periodical = A ['MailingList'];
    	elseif 'mailinglist' == A:ORIGIN('Periodical') then
    		Periodical = '';														-- unset because mailing list is only used for cite mailing list
    	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;
    			ChapterUrlAccess = UrlAccess;
    			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 Cartography = "";
    	local Scale = "";
    	local Sheet = A['Sheet'] or '';
    	local Sheets = A['Sheets'] or '';
    	if config.CitationClass == "map" then
    		Chapter = A['Map'];
    		ChapterURL = A['MapURL'];
    		ChapterUrlAccess = UrlAccess;
    		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.
    	if 'episode' == config.CitationClass or 'serial' == config.CitationClass then
    		local AirDate = A['AirDate'];
    		local SeriesLink = A['SeriesLink'];
    
    		link_title_ok (SeriesLink, A:ORIGIN ('SeriesLink'), Series, 'series');	-- check for wikimarkup in |series-link= or wikimarkup in |series= when |series-link= is set
    
    		local Network = A['Network'];
    		local Station = A['Station'];
    		local s, n = {}, {};
    																				-- do common parameters first
    		if is_set(Network) then table.insert(n, Network); end
    		if is_set(Station) then table.insert(n, Station); end
    		ID = table.concat(n, sepc .. ' ');
    		
    		if not is_set (Date) and is_set (AirDate) then							-- promote airdate to date
    			Date = AirDate;
    		end
    
    		if 'episode' == config.CitationClass then								-- handle the oddities that are strictly {{cite episode}}
    			local Season = A['Season'];
    			local SeriesNumber = A['SeriesNumber'];
    
    			if is_set (Season) and is_set (SeriesNumber) then					-- these are mutually exclusive so if both are set
    				table.insert( z.message_tail, { set_error( 'redundant_parameters', {wrap_style ('parameter', 'season') .. ' and ' .. 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 is_set(Season) then table.insert(s, wrap_msg ('season', Season, use_lowercase)); end
    			if is_set(SeriesNumber) then table.insert(s, wrap_msg ('series', SeriesNumber, use_lowercase)); end
    			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;
    			ChapterUrlAccess = UrlAccess;
    			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 = make_wikilink (ChapterLink, Chapter);
    			elseif is_set (ChapterLink) and is_set (ChapterURL) then			-- if both are set, URL links episode;
    				Series = 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 is_set (Series) and is_set (SeriesLink) then
    				Series = make_wikilink (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}}, {{cite biorxiv}}, {{cite citeseerx}}, before generation of COinS data.
    	do
    		if in_array (config.CitationClass, {'arxiv', 'biorxiv', 'citeseerx'}) then
    			if not is_set (ID_list[config.CitationClass:upper()]) then			-- |arxiv= or |eprint= required for cite arxiv; |biorxiv= & |citeseerx= required for their templates
    				table.insert( z.message_tail, { set_error( config.CitationClass .. '_missing', {}, true ) } );		-- add error message
    			end
    			
    			if 'arxiv' == config.CitationClass then
    				Periodical = 'arXiv';											-- set to arXiv for COinS; after that, must be set to empty string
    			end
    
    			if 'biorxiv' == config.CitationClass then
    				Periodical = 'bioRxiv';											-- set to bioRxiv for COinS; after that, must be set to empty string
    			end
    
    			if 'citeseerx' == config.CitationClass then
    				Periodical = 'CiteSeerX';										-- set to CiteSeerX for COinS; after that, must be set to empty string
    			end
    		end
    	end
    
    	-- handle type parameter for those CS1 citations that have default values
    	if in_array(config.CitationClass, {"AV-media-notes", "interview", "mailinglist", "map", "podcast", "pressrelease", "report", "techreport", "thesis"}) then
    		TitleType = set_titletype (config.CitationClass, TitleType);
    		if is_set(Degree) and "Thesis" == TitleType then						-- special case for cite thesis
    			TitleType = Degree .. ' ' .. cfg.title_types ['thesis']:lower();
    		end
    	end
    
    	if is_set(TitleType) then													-- if type parameter is specified
    		TitleType = 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_origin;															-- to hold the name of parameter promoted to Date; required for date error messaging
    
    	if not 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 is_set (Date) and 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
    	]]
    	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')},
    			['embargo'] = {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')},
    			};
    		anchor_year, Embargo, error_message = dates(date_parameters_list, COinS_date);
    
    -- start temporary Julian / Gregorian calendar uncertainty categorization
    		if COinS_date.inter_cal_cat then
    			add_prop_cat ('jul_greg_uncertainty');
    		end
    -- end temporary Julian / Gregorian calendar uncertainty categorization
    
    		if is_set (Year) and is_set (Date) then									-- both |date= and |year= not normally needed; 
    			local mismatch = year_date_check (Year, Date)
    			if 0 == mismatch then												-- |year= does not match a year-value in |date=
    				if is_set (error_message) then									-- if there is already an error message
    					error_message = error_message .. ', ';						-- tack on this additional message
    				end
    				error_message = error_message .. '&#124;year= / &#124;date= mismatch';
    			elseif 1 == mismatch then											-- |year= matches year-value in |date=
    				add_maint_cat ('date_year');
    			end
    		end
    		
    		if not is_set(error_message) then										-- error free dates only
    			local modified = false;												-- flag
    			
    			if is_set (DF) then													-- if we need to reformat dates
    				modified = reformat_dates (date_parameters_list, DF, false);	-- reformat to DF format, use long month names if appropriate
    			end
    
    			if true == date_hyphen_to_dash (date_parameters_list) then			-- convert hyphens to dashes where appropriate
    				modified = true;
    				add_maint_cat ('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 these three lines.  Not supported by en.wiki (for obvious reasons)
    	-- set date_name_xlate() second argument to true to translate English digits to local digits (will translate ymd dates)
    --			if 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, { set_error( 'bad_date', {error_message}, true ) } );	-- add this error message
    		end
    	end	-- end of do
    
    	-- Account for the oddity that is {{cite journal}} with |pmc= set and |url= not set.  Do this after date check but before COInS.
    	-- 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=
    			if is_set(AccessDate) then											-- access date requires |url=; pmc created url is not |url=
    				table.insert( z.message_tail, { set_error( 'accessdate_missing_url', {}, true ) } );
    				AccessDate = '';												-- unset
    			end
    
    		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 is_set(Title) and
    		not is_set(TransTitle) and
    		not is_set(ScriptTitle) then
    			if 'episode' == config.CitationClass then							-- special case for cite episode; TODO: is there a better way to do this?
    				table.insert( z.message_tail, { set_error( 'citation_missing_title', {'series'}, true ) } );
    			else
    				table.insert( z.message_tail, { set_error( 'citation_missing_title', {'title'}, true ) } );
    			end
    	end
    	
    	if 'none' == Title and in_array (config.CitationClass, {'journal', 'citation'}) and is_set (Periodical) and 'journal' == A:ORIGIN('Periodical') then	-- special case for journal cites
    		Title = '';																-- set title to empty string
    		add_maint_cat ('untitled');
    	end
    
    	check_for_url ({															-- add error message when any of these parameters contains a URL
    		['title']=Title,
    		[A:ORIGIN('Chapter')]=Chapter,
    		[A:ORIGIN('Periodical')]=Periodical,
    		[A:ORIGIN('PublisherName')] = 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 is_set (Encyclopedia)) then
    		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
    	local coins_author = a;														-- default for coins rft.au 
    	if 0 < #c then																-- but if contributor list
    		coins_author = c;														-- use that instead
    	end
    
    	-- this is the function call to COinS()
    	local OCinSoutput = COinS({
    		['Periodical'] = Periodical,
    		['Encyclopedia'] = Encyclopedia,
    		['Chapter'] = make_coins_title (coins_chapter, ScriptChapter),			-- Chapter and ScriptChapter stripped of bold / italic wikimarkup
    		['Degree'] = Degree;													-- cite thesis only
    		['Title'] = make_coins_title (coins_title, ScriptTitle),				-- Title and ScriptTitle stripped of bold / italic wikimarkup
    		['PublicationPlace'] = PublicationPlace,
    		['Date'] = COinS_date.rftdate,											-- COinS_date has correctly formatted date if Date is valid;
    		['Season'] = COinS_date.rftssn,
    		['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 get_coins_pages (first_set ({Sheet, Sheets, Page, Pages, At}, 5)),				-- pages stripped of external links
    		['Edition'] = Edition,
    		['PublisherName'] = PublisherName,
    		['URL'] = first_set ({ChapterURL, URL}, 2),
    		['Authors'] = coins_author,
    		['ID_list'] = ID_list,
    		['RawPage'] = this_page.prefixedText,
    	}, config.CitationClass);
    
    	-- Account for the oddities that are {{cite arxiv}}, {{cite biorxiv}}, and {{cite citeseerx}} AFTER generation of COinS data.
    	if in_array (config.CitationClass, {'arxiv', 'biorxiv', 'citeseerx'}) then	-- we have set rft.jtitle in COinS to arXiv, bioRxiv, or CiteSeerX 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 then
    		if is_set (PublisherName) then
    			PublisherName = substitute (cfg.messages['newsgroup'], external_link( 'news:' .. PublisherName, PublisherName, A:ORIGIN('PublisherName'), nil ));
    		end
    	end
    
    
    
    	-- 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.
    	local EditorCount;															-- used only for choosing {ed.) or (eds.) annotation at end of editor name-list
    	do
    		local last_first_list;
    		local control = { 
    			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
    			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);
    			last_first_list, EditorCount = list_people(control, e, editor_etal);
    
    			if is_set (Editors) then
    				Editors, editor_etal = name_has_etal (Editors, editor_etal, false, 'editors');	-- find and remove variations on et al.
    				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 
    				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);
    			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);
    			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);
    			Contributors = list_people (control, c, contributor_etal);
    --			control.maximum = #c;												-- number of contributors
    --			Contributors = list_people(control, c, false);						-- et al not currently supported
    		end
    		do																		-- now do authors
    			control.maximum , author_etal = get_display_names (A['DisplayAuthors'], #a, 'authors', author_etal);
    
    			last_first_list = list_people(control, a, author_etal);
    
    			if 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 is_set (Authors) and is_set (Collaboration) then
    			Authors = Authors .. ' (' .. Collaboration .. ')';					-- add collaboration after et al.
    		end
    
    	end
    
    	-- apply |[xx-]format= styling; at the end, these parameters hold correctly styled format annotation,
    	-- an error message if the associated url is not set, or an empty string for concatenation
    	ArchiveFormat = style_format (ArchiveFormat, ArchiveURL, 'archive-format', 'archive-url');
    	ConferenceFormat = style_format (ConferenceFormat, ConferenceURL, 'conference-format', 'conference-url');
    	Format = style_format (Format, URL, 'format', 'url');
    	LayFormat = style_format (LayFormat, LayURL, 'lay-format', 'lay-url');
    	TranscriptFormat = style_format (TranscriptFormat, TranscriptURL, 'transcript-format', 'transcripturl');
    
    	-- special case for chapter format so no error message or cat when chapter not supported
    	if not (in_array(config.CitationClass, {'web', 'news', 'journal', 'magazine', 'pressrelease', 'podcast', 'newsgroup', 'arxiv', 'biorxiv', 'citeseerx'}) or
    		('citation' == config.CitationClass and is_set (Periodical) and not is_set (Encyclopedia))) then
    			ChapterFormat = style_format (ChapterFormat, ChapterURL, 'chapter-format', 'chapter-url');
    	end
    
    	if not is_set(URL) then
    		if in_array(config.CitationClass, {"web","podcast", "mailinglist"}) then	-- |url= required for cite web, cite podcast, and cite mailinglist
    			table.insert( z.message_tail, { set_error( 'cite_web_url', {}, true ) } );
    		end
    		
    		-- do we have |accessdate= without either |url= or |chapter-url=?
    		if is_set(AccessDate) and not is_set(ChapterURL)then					-- ChapterURL may be set when URL is not set;
    			table.insert( z.message_tail, { set_error( 'accessdate_missing_url', {}, true ) } );
    			AccessDate = '';
    		end
    	end
    
    	local OriginalURL, OriginalURLorigin, OriginalFormat, OriginalAccess;
    	DeadURL = DeadURL:lower();													-- used later when assembling archived text
    	if is_set( ArchiveURL ) then
    		if 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
    			OriginalURLorigin = ChapterURLorigin;								-- name of chapter-url parameter for error messages
    			OriginalFormat = ChapterFormat;										-- and original |chapter-format=
    			if 'no' ~= DeadURL then
    				ChapterURL = ArchiveURL											-- swap-in the archive's url
    				ChapterURLorigin = 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 is_set (URL) then
    			OriginalURL = URL;													-- save copy of original source URL
    			OriginalURLorigin = URLorigin;										-- name of url parameter for error messages
    			OriginalFormat = Format; 											-- and original |format=
    			OriginalAccess = UrlAccess;
    			if 'no' ~= DeadURL then												-- if URL set then archive-url applies to it
    				URL = ArchiveURL												-- swap-in the archive's url
    				URLorigin = 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 in_array(config.CitationClass, {'web','news','journal', 'magazine', 'pressrelease', 'podcast', 'newsgroup', 'arxiv', 'biorxiv', 'citeseerx'}) or	-- if any of the 'periodical' cites except encyclopedia
    		('citation' == config.CitationClass and is_set (Periodical) and not is_set (Encyclopedia)) then
    			local chap_param;
    			if is_set (Chapter) then											-- get a parameter name from one of these chapter related meta-parameters
    				chap_param = A:ORIGIN ('Chapter')
    			elseif is_set (TransChapter) then
    				chap_param = A:ORIGIN ('TransChapter')
    			elseif is_set (ChapterURL) then
    				chap_param = A:ORIGIN ('ChapterURL')
    			elseif is_set (ScriptChapter) then
    				chap_param = A:ORIGIN ('ScriptChapter')
    			else is_set (ChapterFormat)
    				chap_param = A:ORIGIN ('ChapterFormat')
    			end
    
    			if is_set (chap_param) then											-- if we found one
    				table.insert( z.message_tail, { set_error( '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 is_set (Contribution) and 0 < #c then								-- if this is a contribution with contributor(s)
    			if in_array (Contribution:lower(), cfg.keywords.contribution) then	-- and a generic contribution title
    				no_quotes = true;												-- then render it unquoted
    			end
    		end
    
    		Chapter = format_chapter_title (ScriptChapter, Chapter, TransChapter, ChapterURL, ChapterURLorigin, no_quotes, ChapterUrlAccess);		-- Contribution is also in Chapter
    		if is_set (Chapter) then
    			Chapter = Chapter .. ChapterFormat ;
    			if 'map' == config.CitationClass and is_set (TitleType) then
    				Chapter = Chapter .. ' ' .. TitleType;							-- map annotation here; not after title
    			end
    			Chapter = Chapter.. sepc .. ' ';
    		elseif 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.
    	if is_set (ArchiveURL) and mw.ustring.match (mw.ustring.lower(Title), cfg.special_case_translation['archived_copy']) then	-- if title is 'Archived copy' (place holder added by bots that can't find proper title)
    		add_maint_cat ('archived_copy');										-- add maintenance category before we modify the content of Title
    	end
    
    	if Title:match ('^%(%(.*%)%)$') then										-- if keep as written markup:
    		Title= Title:gsub ('^%(%((.*)%)%)$', '%1')								-- remove the markup
    	else
    		if '...' == Title:sub (-3) then											-- if elipsis 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 in_array(config.CitationClass, {'web', 'news', 'journal', 'magazine', 'pressrelease', 'podcast', 'newsgroup', 'mailinglist', 'interview', 'arxiv', 'biorxiv', 'citeseerx'}) or
    		('citation' == config.CitationClass and is_set (Periodical) and not is_set (Encyclopedia)) or
    		('map' == config.CitationClass and is_set (Periodical)) 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 = wrap_style ('quoted-title', Title);
    			Title = script_concatenate (Title, ScriptTitle);					-- <bdi> tags, lang atribute, categorization, etc; must be done after title is wrapped
    			TransTitle= wrap_style ('trans-quoted-title', TransTitle );
    	elseif 'report' == config.CitationClass then								-- no styling for cite report
    		Title = script_concatenate (Title, ScriptTitle);						-- <bdi> tags, lang atribute, categorization, etc; must be done after title is wrapped
    		TransTitle= wrap_style ('trans-quoted-title', TransTitle );				-- for cite report, use this form for trans-title
    	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
    
    	local TransError = "";
    	if is_set(TransTitle) then
    		if is_set(Title) then
    			TransTitle = " " .. TransTitle;
    		else
    			TransError = " " .. set_error( 'trans_missing_title', {'title'} );
    		end
    	end
    
    	if is_set(Title) then
    		if not is_set (TitleLink) and is_set (URL) then
    			Title = external_link (URL, Title, URLorigin, UrlAccess) .. TransTitle .. TransError .. Format;
    			URL = '';															-- unset these because no longer needed
    			Format = "";
    		elseif is_set (TitleLink) and not 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 = substitute (cfg.presentation['interwiki-icon'], {cfg.presentation['class-wikisource'], TitleLink, Title});				
    				Title = Title .. TransTitle .. TransError;
    			else
    				Title = make_wikilink (TitleLink, Title) .. TransTitle .. TransError;
    			end
    		else
    			local ws_url, ws_label;
    			ws_url, ws_label, L = wikisource_url_make (Title);					-- make ws url from |title= interwiki link; link portion L becomes tool tip 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 = 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 is_set(Place) then
    		Place = " " .. wrap_msg ('written', Place, use_lowercase) .. sepc .. " ";
    	end
    
    	if is_set (Conference) then
    		if is_set (ConferenceURL) then
    			Conference = external_link( ConferenceURL, Conference, ConferenceURLorigin, nil );
    		end
    		Conference = sepc .. " " .. Conference .. ConferenceFormat;
    	elseif is_set(ConferenceURL) then
    		Conference = sepc .. " " .. external_link( ConferenceURL, nil, ConferenceURLorigin, nil );
    	end
    
    	if not is_set(Position) then
    		local Minutes = A['Minutes'];
    		local Time = A['Time'];
    
    		if is_set(Minutes) then
    			if is_set (Time) then
    				table.insert( z.message_tail, { set_error( 'redundant_parameters', {wrap_style ('parameter', 'minutes') .. ' and ' .. wrap_style ('parameter', 'time')}, true ) } );
    			end
    			Position = " " .. Minutes .. " " .. cfg.messages['minutes'];
    		else
    			if is_set(Time) then
    				local TimeCaption = A['TimeCaption']
    				if not 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 = is_set(At) and (sepc .. " " .. At) or "";
    	Position = is_set(Position) and (sepc .. " " .. Position) or "";
    	if config.CitationClass == 'map' then
    		local Section = A['Section'];
    		local Sections = A['Sections'];
    		local Inset = A['Inset'];
    		
    		if is_set( Inset ) then
    			Inset = sepc .. " " .. wrap_msg ('inset', Inset, use_lowercase);
    		end			
    
    		if is_set( Sections ) then
    			Section = sepc .. " " .. wrap_msg ('sections', Sections, use_lowercase);
    		elseif is_set( Section ) then
    			Section = sepc .. " " .. wrap_msg ('section', Section, use_lowercase);
    		end
    		At = At .. Inset .. Section;		
    	end	
    
    	if 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
    
    	Others = is_set(Others) and (sepc .. " " .. Others) or "";
    	
    	if is_set (Translators) then
    		Others = safe_join ({sepc .. ' ', wrap_msg ('translated', Translators, use_lowercase), Others}, sepc);
    	end
    	if is_set (Interviewers) then
    		Others = safe_join ({sepc .. ' ', wrap_msg ('interview', Interviewers, use_lowercase), Others}, sepc);
    	end
    	
    	TitleNote = is_set(TitleNote) and (sepc .. " " .. TitleNote) or "";
    	if is_set (Edition) then
    		if Edition:match ('%f[%a][Ee]d%.?$') or Edition:match ('%f[%a][Ee]dition$') then
    			add_maint_cat ('extra_text', 'edition');
    		end
    		Edition = " " .. wrap_msg ('edition', Edition);
    	else
    		Edition = '';
    	end
    
    	Series = is_set(Series) and (sepc .. " " .. Series) or "";
    		OrigYear = is_set(OrigYear) and (" [" .. OrigYear .. "]") or "";		-- TODO: presentation
    
    	Agency = is_set(Agency) and (sepc .. " " .. Agency) or "";
    
    	Volume = format_volume_issue (Volume, Issue, config.CitationClass, Periodical_origin, sepc, use_lowercase);
    
    	------------------------------------ totally unrelated data
    	if is_set(Via) then
    		Via = " " .. wrap_msg ('via', Via);
    	end
    
    	--[[
    	Subscription implies paywall; Registration does not.  If both are used in a citation, the subscription required link
    	note is displayed. There are no error messages for this condition.
    	
    	]]
    	if is_set (SubscriptionRequired) then
    		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
    
    	if 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 = substitute (retrv_text, AccessDate);						-- add retrieved text
    
    		AccessDate = substitute (cfg.presentation['accessdate'], {sepc, AccessDate});	-- allow editors to hide accessdates
    	end
    	
    	if is_set(ID) then ID = sepc .." ".. ID; end
       	if "thesis" == config.CitationClass and is_set(Docket) then
    		ID = sepc .." Docket ".. Docket .. ID;
    	end
       	if "report" == config.CitationClass and is_set(Docket) then					-- for cite report when |docket= is set
    		ID = sepc .. ' ' .. Docket;												-- overwrite ID even if |id= is set
    	end
    
    	ID_list = build_id_list( ID_list, {IdAccessLevels=ID_access_levels, DoiBroken = DoiBroken, ASINTLD = ASINTLD, IgnoreISBN = IgnoreISBN, Embargo=Embargo, Class = Class} );
    
    	if is_set(URL) then
    		URL = " " .. external_link( URL, nil, URLorigin, UrlAccess );
    	end
    
    	if 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
    		Quote = sepc .." " .. wrap_style ('quoted-text', Quote ); 				-- wrap in <q>...</q> tags
    		PostScript = "";														-- cs1|2 does not supply terminal punctuation when |quote= is set
    	end
    	
    	local Archived
    	if is_set(ArchiveURL) then
    		if not is_set(ArchiveDate) then
    			ArchiveDate = set_error('archive_missing_date');
    		end
    		if "no" == DeadURL then
    			local arch_text = cfg.messages['archived'];
    			if sepc ~= "." then arch_text = arch_text:lower() end
    			Archived = sepc .. " " .. substitute( cfg.messages['archived-not-dead'],
    				{ external_link( ArchiveURL, arch_text, A:ORIGIN('ArchiveURL'), nil ) .. ArchiveFormat, ArchiveDate } );
    			if not is_set(OriginalURL) then
    				Archived = Archived .. " " .. set_error('archive_missing_url');							   
    			end
    		elseif is_set(OriginalURL) then											-- DeadURL is empty, 'yes', 'true', 'y', 'unfit', 'usurped'
    			local arch_text = cfg.messages['archived-dead'];
    			if sepc ~= "." then arch_text = arch_text:lower() end
    			if in_array (DeadURL, {'unfit', 'usurped', 'bot: unknown'}) then
    				Archived = sepc .. " " .. 'Archived from the original on ' .. ArchiveDate;	-- format already styled
    				if 'bot: unknown' == DeadURL then
    					add_maint_cat ('bot:_unknown');								-- and add a category if not already added
    				else
    					add_maint_cat ('unfit');									-- and add a category if not already added
    				end
    			else																-- DeadURL is empty, 'yes', 'true', or 'y'
    				Archived = sepc .. " " .. substitute( arch_text,
    					{ external_link( OriginalURL, cfg.messages['original'], OriginalURLorigin, OriginalAccess ) .. 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
    	elseif is_set (ArchiveFormat) then
    		Archived = ArchiveFormat;												-- if set and ArchiveURL not set ArchiveFormat has error message
    	else
    		Archived = ""
    	end
    	
    	local Lay = '';
    	if is_set(LayURL) then
    		if is_set(LayDate) then LayDate = " (" .. LayDate .. ")" end
    		if is_set(LaySource) then 
    			LaySource = " &ndash; ''" .. 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 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
    
    	if is_set(Transcript) then
    		if is_set(TranscriptURL) then
    			Transcript = external_link( TranscriptURL, Transcript, TranscriptURLorigin, nil );
    		end
    		Transcript = sepc .. ' ' .. Transcript .. TranscriptFormat;
    	elseif is_set(TranscriptURL) then
    		Transcript = external_link( TranscriptURL, nil, TranscriptURLorigin, nil );
    	end
    
    	local Publisher;
    	if is_set(PublicationDate) then
    		PublicationDate = wrap_msg ('published', PublicationDate);
    	end
    	if is_set(PublisherName) then
    		if is_set(PublicationPlace) then
    			Publisher = sepc .. " " .. PublicationPlace .. ": " .. PublisherName .. PublicationDate;
    		else
    			Publisher = sepc .. " " .. PublisherName .. PublicationDate;  
    		end			
    	elseif is_set(PublicationPlace) then 
    		Publisher= sepc .. " " .. PublicationPlace .. PublicationDate;
    	else 
    		Publisher = PublicationDate;
    	end
    	
    	-- Several of the above rely upon detecting this as nil, so do it last.
    	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
    
    	--[[
    	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 is_set (Periodical) then							-- if Periodical, perhaps because of an included |website= or |journal= parameter 
    			if 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 in_array(config.CitationClass, {"journal","citation"}) and is_set(Periodical) then
    		if 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 in_array(config.CitationClass, {"book","citation"}) and not is_set(Periodical) then		-- special cases for book cites
    		if 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 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}, 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 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, SubscriptionRequired, Lay, Quote }, sepc );
    	else
    		idcommon = safe_join( { ID_list, URL, Archived, AccessDate, Via, SubscriptionRequired, Lay, Quote }, sepc );
    	end
    	
    	local text;
    	local pgtext = Position .. Sheet .. Sheets .. Page .. Pages .. At;
    
    	if is_set(Date) then
    		if is_set (Authors) or is_set (Editors) then							-- date follows authors or editors when authors not set
    			Date = " (" .. Date ..")" .. OrigYear .. sepc .. " ";				-- in paranetheses
    		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 .. OrigYear;									-- Date does not begin with sepc
    			else
    				Date = sepc .. " " .. Date .. OrigYear;							-- Date begins with sepc
    			end
    		end
    	end	
    	if is_set(Authors) then
    		if (not 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 is_set(Editors) then
    			local in_text = " ";
    			local post_text = "";
    			if 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 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 is_set (Editors) and 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 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 is_set(Editors) then
    		if 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 in_array(config.CitationClass, {"journal","citation"}) and 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 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 is_set(config.CitationClass) and config.CitationClass ~= "citation" then
    		options.class = config.CitationClass;
    		options.class = "citation " .. config.CitationClass;					-- class=citation required for blue highlight when used with |ref=
    	else
    		options.class = "citation";
    	end
    	
    	if is_set(Ref) and Ref:lower() ~= "none" then								-- set reference anchor if appropriate
    		local id = Ref
    		if ('harv' == Ref ) then
    			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
    			if #namelist > 0 then												-- if there are names in namelist
    				id = anchor_id (namelist, year);								-- go make the CITEREF anchor
    			else
    				id = '';														-- unset
    			end
    		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 = set_error('empty_citation');
    		z.message_tail = {};
    	end
    	
    	local render = {};															-- here we collect the final bits for concatenation into the rendered citation
    
    	if is_set(options.id) then													-- here we wrap the rendered citation in <cite ...>...</cite> tags
    		table.insert (render, substitute (cfg.presentation['cite-id'], {mw.uri.anchorEncode(options.id), mw.text.nowiki(options.class), text}));	-- when |ref= is set
    	else
    		table.insert (render, substitute (cfg.presentation['cite'], {mw.text.nowiki(options.class), text}));	-- all other cases
    	end		
    
    	table.insert (render, 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 is_set(v[1]) then
    				if i == #z.message_tail then
    					table.insert (render, error_comment( v[1], v[2] ));
    				else
    					table.insert (render, 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, make_wikilink (':Category:' .. v, 'link'));	-- 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, substitute (cfg.presentation['hidden-maint'], table.concat (maint_msgs, ' ')));	-- wrap the group of maint message with proper presentation and save
    	end
    	
    	no_tracking_cats = no_tracking_cats:lower();
    	if in_array(no_tracking_cats, {"", "no", "false", "n"}) then
    		for _, v in ipairs( z.error_categories ) do
    			table.insert (render, make_wikilink ('Category:' .. v));
    		end
    		for _, v in ipairs( z.maintenance_cats ) do								-- append maintenance categories
    			table.insert (render, make_wikilink ('Category:' .. v));
    		end
    		for _, v in ipairs( z.properties_cats ) do								-- append properties categories
    			table.insert (render, make_wikilink ('Category:' .. 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)
    	local name = tostring (name);
    	local state;
    	
    	if in_array (cite_class, {'arxiv', 'biorxiv', 'citeseerx'}) then			-- limited parameter sets allowed for these templates
    		state = whitelist.limited_basic_arguments[name];
    		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
    
    		state = whitelist[cite_class .. '_basic_arguments'][name];				-- look in the parameter-list for the template identified by cite_class
    
    		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
    																				-- limited enumerated parameters list
    		name = name:gsub("%d+", "#" );											-- replace digit(s) with # (last25 becomes last#) (mw.ustring because non-Western 'local' digits)
    		state = whitelist.limited_numbered_arguments[name];
    		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
    
    		return false;															-- not supported because not found or name is set to nil
    	end																			-- end limited parameter-set templates
    		
    	state = whitelist.basic_arguments[name];									-- all other templates; all normal parameters allowed
    											
    	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
    																				-- all enumerated parameters allowed
    	name = name:gsub("%d+", "#" );												-- replace digit(s) with # (last25 becomes last#) (mw.ustring because non-Western 'local' digits)
    	state = whitelist.numbered_arguments[name];
    
    	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
    	
    	return false;																-- not supported because not found or name is set to nil
    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:
    	{{cite ... |title=Title access-date=2016-03-17}}
    
    cs1|2 shares some parameter names with xml/html atributes: 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[%a%d]+)%s*=') or value:match ('^(%a[%a%d]+)%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, {set_error ('missing_pipe',parameter)});
    	end
    end
    
    
    --[[--------------------------< C S 1 . 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 incase we need to display an error message in preview mode
    	local pframe = frame:getParent()
    	local validation, utilities, identifiers, metadata, 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 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
    
    	dates = validation.dates;													-- imported functions from Module:Citation/CS1/Date validation
    	year_date_check = validation.year_date_check;
    	reformat_dates = validation.reformat_dates;
    	date_hyphen_to_dash = validation.date_hyphen_to_dash;
    	date_name_xlate = validation.date_name_xlate;
    
    	is_set = utilities.is_set;													-- imported functions from Module:Citation/CS1/Utilities
    	in_array = utilities.in_array;
    	substitute = utilities.substitute;
    	error_comment = utilities.error_comment;
    	set_error = utilities.set_error;
    	select_one = utilities.select_one;
    	add_maint_cat = utilities.add_maint_cat;
    	wrap_style = utilities.wrap_style;
    	safe_for_italics = utilities.safe_for_italics;
    	is_wikilink = utilities.is_wikilink;
    	make_wikilink = utilities.make_wikilink;
    
    	z = utilities.z;															-- table of error and category tables in Module:Citation/CS1/Utilities
    
    	extract_ids = identifiers.extract_ids;										-- imported functions from Module:Citation/CS1/Identifiers
    	build_id_list = identifiers.build_id_list;
    	is_embargoed = identifiers.is_embargoed;
    	extract_id_access_levels = identifiers.extract_id_access_levels;
    	
    	make_coins_title = metadata.make_coins_title;								-- imported functions from Module:Citation/CS1/COinS
    	get_coins_pages = metadata.get_coins_pages;
    	COinS = metadata.COinS;
    
    	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
    		config[k] = v;
    --		args[k] = v;															-- debug tool that allows us to render a citation from module {{#invoke:}}
    	end	
    
    	local capture;																-- the single supported capture when matching unknown parameters using patterns
    	for k, v in pairs( pframe.args ) do
    		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 = set_error( 'text_ignored', {v}, true );
    					end
    				elseif validate( k:lower(), config.CitationClass ) then 
    					error_text, error_state = set_error( '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 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)
    							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 = set_error ('parameter_ignored_suggest', {k, param}, true);	-- set the suggestion error message
    							else
    								error_text, error_state = set_error( 'parameter_ignored', {param}, true );	-- suggested param not supported by this template
    							end
    						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 );
    							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
    			missing_pipe_check (k, v);												-- do we think that there is a parameter that is missing a pipe?
    																				-- TODO: is this the best place for this translation?
    			args[k] = v;
    		elseif args[k] ~= nil or (k == 'postscript') then						-- here when v is empty string
    			args[k] = v;														-- why do we do this?  we don't support 'empty' parameters
    		end		
    	end	
    
    	for k, v in pairs( args ) do
    		if 'string' == type (k) then											-- don't evaluate positional parameters
    			has_invisible_chars (k, v);
    		end
    	end
    	return table.concat ({citation0( config, args), frame:extensionTag ('templatestyles', '', {src=styles})});
    end
    
    --[[--------------------------< E X P O R T E D   F U N C T I O N S >------------------------------------------
    ]]
    
    return {citation = citation};