Module:String: Difference between revisions

Created page with "-- <nowiki> --[[ Source: http://en.wikipedia.org/wiki/Module:String This module is intended to provide access to basic string functions. Most of the functions provided her..."
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imported>Unai01
(Created page with "-- <nowiki> --[[ Source: http://en.wikipedia.org/wiki/Module:String This module is intended to provide access to basic string functions. Most of the functions provided her...")
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-- <nowiki>
--[[   
--[[   
 
Source: http://en.wikipedia.org/wiki/Module:String
This module is intended to provide access to basic string functions.
This module is intended to provide access to basic string functions.
 
Most of the functions provided here can be invoked with named parameters,  
Most of the functions provided here can be invoked with named parameters,  
unnamed parameters, or a mixture.  If named parameters are used, Mediawiki will  
unnamed parameters, or a mixture.  If named parameters are used, Mediawiki will  
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Depending on the intended use, it may be advantageous to either preserve or
Depending on the intended use, it may be advantageous to either preserve or
remove such whitespace.
remove such whitespace.
 
Global options
Global options
     ignore_errors: If set to 'true' or 1, any error condition will result in  
     ignore_errors: If set to 'true' or 1, any error condition will result in  
         an empty string being returned rather than an error message.   
         an empty string being returned rather than an error message.   
       
     error_category: If an error occurs, specifies the name of a category to  
     error_category: If an error occurs, specifies the name of a category to  
         include with the error message.  The default category is   
         include with the error message.  The default category is   
         [Category:Errors reported by Module String].
         [Category:Errors reported by Module String].
       
     no_category: If set to 'true' or 1, no category will be added if an error
     no_category: If set to 'true' or 1, no category will be added if an error
         is generated.
         is generated.
       
Unit tests for this module are available at Module:String/tests.
Unit tests for this module are available at Module:String/tests.
]]
]]
 
local str = {}
local str = {}
 
--[[
--[[
len
len
 
This function returns the length of the target string.
This function returns the length of the target string.
 
Usage:
Usage:
{{#invoke:String|len|target_string|}}
{{#invoke:String|len|target_string|}}
OR
OR
{{#invoke:String|len|s=target_string}}
{{#invoke:String|len|s=target_string}}
 
Parameters
Parameters
     s: The string whose length to report
     s: The string whose length to report
 
If invoked using named parameters, Mediawiki will automatically remove any leading or
If invoked using named parameters, Mediawiki will automatically remove any leading or
trailing whitespace from the target string.   
trailing whitespace from the target string.   
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     return mw.ustring.len( s )
     return mw.ustring.len( s )
end
end
 
--[[
--[[
sub
sub
 
This function returns a substring of the target string at specified indices.
This function returns a substring of the target string at specified indices.
 
Usage:
Usage:
{{#invoke:String|sub|target_string|start_index|end_index}}
{{#invoke:String|sub|target_string|start_index|end_index}}
OR
OR
{{#invoke:String|sub|s=target_string|i=start_index|j=end_index}}
{{#invoke:String|sub|s=target_string|i=start_index|j=end_index}}
 
Parameters
Parameters
     s: The string to return a subset of
     s: The string to return a subset of
     i: The fist index of the substring to return, defaults to 1.
     i: The fist index of the substring to return, defaults to 1.
     j: The last index of the string to return, defaults to the last character.
     j: The last index of the string to return, defaults to the last character.
   
The first character of the string is assigned an index of 1.  If either i or j
The first character of the string is assigned an index of 1.  If either i or j
is a negative value, it is interpreted the same as selecting a character by  
is a negative value, it is interpreted the same as selecting a character by  
counting from the end of the string.  Hence, a value of -1 is the same as  
counting from the end of the string.  Hence, a value of -1 is the same as  
selecting the last character of the string.
selecting the last character of the string.
 
If the requested indices are out of range for the given string, an error is  
If the requested indices are out of range for the given string, an error is  
reported.
reported.
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     local i = tonumber( new_args['i'] ) or 1;
     local i = tonumber( new_args['i'] ) or 1;
     local j = tonumber( new_args['j'] ) or -1;
     local j = tonumber( new_args['j'] ) or -1;
   
     local len = mw.ustring.len( s );
     local len = mw.ustring.len( s );
 
     -- Convert negatives for range checking
     -- Convert negatives for range checking
     if i < 0 then
     if i < 0 then
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         j = len + j + 1;
         j = len + j + 1;
     end
     end
   
     if i > len or j > len or i < 1 or j < 1 then
     if i > len or j > len or i < 1 or j < 1 then
         return str._error( 'String subset index out of range' );
         return str._error( 'String subset index out of range' );
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         return str._error( 'String subset indices out of order' );
         return str._error( 'String subset indices out of order' );
     end
     end
   
     return mw.ustring.sub( s, i, j )
     return mw.ustring.sub( s, i, j )
end
end
 
--[[
--[[
This function implements that features of {{str sub old}} and is kept in order
This function implements that features of {{str sub old}} and is kept in order
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     return mw.ustring.sub( frame.args.s, i + 1, len and ( i + len ) )
     return mw.ustring.sub( frame.args.s, i + 1, len and ( i + len ) )
end
end
 
--[[
--[[
match
match
 
This function returns a substring from the source string that matches a  
This function returns a substring from the source string that matches a  
specified pattern.
specified pattern.
 
Usage:
Usage:
{{#invoke:String|match|source_string|pattern_string|start_index|match_number|plain_flag|nomatch_output}}
{{#invoke:String|match|source_string|pattern_string|start_index|match_number|plain_flag|nomatch_output}}
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{{#invoke:String|match|s=source_string|pattern=pattern_string|start=start_index
{{#invoke:String|match|s=source_string|pattern=pattern_string|start=start_index
     |match=match_number|plain=plain_flag|nomatch=nomatch_output}}
     |match=match_number|plain=plain_flag|nomatch=nomatch_output}}
 
Parameters
Parameters
     s: The string to search
     s: The string to search
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         text.  Defaults to false.
         text.  Defaults to false.
     nomatch: If no match is found, output the "nomatch" value rather than an error.
     nomatch: If no match is found, output the "nomatch" value rather than an error.
 
If invoked using named parameters, Mediawiki will automatically remove any leading or
If invoked using named parameters, Mediawiki will automatically remove any leading or
trailing whitespace from each string.  In some circumstances this is desirable, in  
trailing whitespace from each string.  In some circumstances this is desirable, in  
other cases one may want to preserve the whitespace.
other cases one may want to preserve the whitespace.
 
If the match_number or start_index are out of range for the string being queried, then
If the match_number or start_index are out of range for the string being queried, then
this function generates an error.  An error is also generated if no match is found.
this function generates an error.  An error is also generated if no match is found.
If one adds the parameter ignore_errors=true, then the error will be suppressed and  
If one adds the parameter ignore_errors=true, then the error will be suppressed and  
an empty string will be returned on any failure.
an empty string will be returned on any failure.
 
For information on constructing Lua patterns, a form of [regular expression], see:
For information on constructing Lua patterns, a form of [regular expression], see:
 
* https://www.lua.org/manual/5.1/manual.html#5.4.1
* http://www.lua.org/manual/5.1/manual.html#5.4.1
* https://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Patterns
* http://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Patterns
* https://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Ustring_patterns
* http://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Ustring_patterns
 
]]
]]
function str.match( frame )
function str.match( frame )
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     local match_index = math.floor( tonumber(new_args['match']) or 1 );
     local match_index = math.floor( tonumber(new_args['match']) or 1 );
     local nomatch = new_args['nomatch'];
     local nomatch = new_args['nomatch'];
   
     if s == '' then
     if s == '' then
         return str._error( 'Target string is empty' );
         return str._error( 'Target string is empty' );
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         pattern = str._escapePattern( pattern );
         pattern = str._escapePattern( pattern );
     end
     end
   
     local result
     local result
     if match_index == 1 then
     if match_index == 1 then
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             s = mw.ustring.sub( s, start );
             s = mw.ustring.sub( s, start );
         end
         end
       
         local iterator = mw.ustring.gmatch(s, pattern);
         local iterator = mw.ustring.gmatch(s, pattern);
         if match_index > 0 then
         if match_index > 0 then
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                 count = count + 1;
                 count = count + 1;
             end
             end
           
             result = result_table[ count + match_index ];             
             result = result_table[ count + match_index ];             
         end
         end
     end         
     end         
   
     if result == nil then
     if result == nil then
         if nomatch == nil then
         if nomatch == nil then
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     end
     end
end
end
 
--[[
--[[
pos
pos
 
This function returns a single character from the target string at position pos.
This function returns a single character from the target string at position pos.
 
Usage:
Usage:
{{#invoke:String|pos|target_string|index_value}}
{{#invoke:String|pos|target_string|index_value}}
OR
OR
{{#invoke:String|pos|target=target_string|pos=index_value}}
{{#invoke:String|pos|target=target_string|pos=index_value}}
 
Parameters
Parameters
     target: The string to search
     target: The string to search
     pos: The index for the character to return
     pos: The index for the character to return
 
If invoked using named parameters, Mediawiki will automatically remove any leading or
If invoked using named parameters, Mediawiki will automatically remove any leading or
trailing whitespace from the target string.  In some circumstances this is desirable, in  
trailing whitespace from the target string.  In some circumstances this is desirable, in  
other cases one may want to preserve the whitespace.
other cases one may want to preserve the whitespace.
 
The first character has an index value of 1.
The first character has an index value of 1.
 
If one requests a negative value, this function will select a character by counting backwards  
If one requests a negative value, this function will select a character by counting backwards  
from the end of the string.  In other words pos = -1 is the same as asking for the last character.
from the end of the string.  In other words pos = -1 is the same as asking for the last character.
 
A requested value of zero, or a value greater than the length of the string returns an error.
A requested value of zero, or a value greater than the length of the string returns an error.
]]
]]
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     local target_str = new_args['target'] or '';
     local target_str = new_args['target'] or '';
     local pos = tonumber( new_args['pos'] ) or 0;
     local pos = tonumber( new_args['pos'] ) or 0;
 
     if pos == 0 or math.abs(pos) > mw.ustring.len( target_str ) then
     if pos == 0 or math.abs(pos) > mw.ustring.len( target_str ) then
         return str._error( 'String index out of range' );
         return str._error( 'String index out of range' );
     end     
     end     
   
     return mw.ustring.sub( target_str, pos, pos );
     return mw.ustring.sub( target_str, pos, pos );
end
end
 
--[[
--[[
str_find
str_find
 
This function duplicates the behavior of {{str_find}}, including all of its quirks.
This function duplicates the behavior of {{str_find}}, including all of its quirks.
This is provided in order to support existing templates, but is NOT RECOMMENDED for  
This is provided in order to support existing templates, but is NOT RECOMMENDED for  
new code and templates.  New code is recommended to use the "find" function instead.
new code and templates.  New code is recommended to use the "find" function instead.
 
Returns the first index in "source" that is a match to "target".  Indexing is 1-based,
Returns the first index in "source" that is a match to "target".  Indexing is 1-based,
and the function returns -1 if the "target" string is not present in "source".
and the function returns -1 if the "target" string is not present in "source".
 
Important Note: If the "target" string is empty / missing, this function returns a
Important Note: If the "target" string is empty / missing, this function returns a
value of "1", which is generally unexpected behavior, and must be accounted for
value of "1", which is generally unexpected behavior, and must be accounted for
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     local source_str = new_args['source'] or '';
     local source_str = new_args['source'] or '';
     local target_str = new_args['target'] or '';
     local target_str = new_args['target'] or '';
 
     if target_str == '' then
     if target_str == '' then
         return 1;
         return 1;
     end     
     end     
   
     local start = mw.ustring.find( source_str, target_str, 1, true )
     local start = mw.ustring.find( source_str, target_str, 1, true )
     if start == nil then
     if start == nil then
         start = -1
         start = -1
     end
     end
   
     return start
     return start
end
end
 
--[[
--[[
find
find
 
This function allows one to search for a target string or pattern within another
This function allows one to search for a target string or pattern within another
string.
string.
 
Usage:
Usage:
{{#invoke:String|find|source_str|target_string|start_index|plain_flag}}
{{#invoke:String|find|source_str|target_string|start_index|plain_flag}}
OR
OR
{{#invoke:String|find|source=source_str|target=target_str|start=start_index|plain=plain_flag}}
{{#invoke:String|find|source=source_str|target=target_str|start=start_index|plain=plain_flag}}
 
Parameters
Parameters
     source: The string to search
     source: The string to search
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     plain: Boolean flag indicating that target should be understood as plain
     plain: Boolean flag indicating that target should be understood as plain
         text and not as a Lua style regular expression, defaults to true
         text and not as a Lua style regular expression, defaults to true
 
If invoked using named parameters, Mediawiki will automatically remove any leading or
If invoked using named parameters, Mediawiki will automatically remove any leading or
trailing whitespace from the parameter.  In some circumstances this is desirable, in  
trailing whitespace from the parameter.  In some circumstances this is desirable, in  
other cases one may want to preserve the whitespace.
other cases one may want to preserve the whitespace.
 
This function returns the first index >= "start" where "target" can be found  
This function returns the first index >= "start" where "target" can be found  
within "source".  Indices are 1-based.  If "target" is not found, then this  
within "source".  Indices are 1-based.  If "target" is not found, then this  
function returns 0.  If either "source" or "target" are missing / empty, this
function returns 0.  If either "source" or "target" are missing / empty, this
function also returns 0.
function also returns 0.
 
This function should be safe for UTF-8 strings.
This function should be safe for UTF-8 strings.
]]
]]
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     local start_pos = tonumber(new_args['start']) or 1;
     local start_pos = tonumber(new_args['start']) or 1;
     local plain = new_args['plain'] or true;
     local plain = new_args['plain'] or true;
       
     if source_str == '' or pattern == '' then
     if source_str == '' or pattern == '' then
         return 0;
         return 0;
     end     
     end     
   
     plain = str._getBoolean( plain );
     plain = str._getBoolean( plain );
 
     local start = mw.ustring.find( source_str, pattern, start_pos, plain )
     local start = mw.ustring.find( source_str, pattern, start_pos, plain )
     if start == nil then
     if start == nil then
         start = 0
         start = 0
     end
     end
   
     return start
     return start
end
end
 
--[[
--[[
replace
replace
 
This function allows one to replace a target string or pattern within another
This function allows one to replace a target string or pattern within another
string.
string.
 
Usage:
Usage:
{{#invoke:String|replace|source_str|pattern_string|replace_string|replacement_count|plain_flag}}
{{#invoke:String|replace|source_str|pattern_string|replace_string|replacement_count|plain_flag}}
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{{#invoke:String|replace|source=source_string|pattern=pattern_string|replace=replace_string|
{{#invoke:String|replace|source=source_string|pattern=pattern_string|replace=replace_string|
   count=replacement_count|plain=plain_flag}}
   count=replacement_count|plain=plain_flag}}
 
Parameters
Parameters
     source: The string to search
     source: The string to search
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     local count = tonumber( new_args['count'] );
     local count = tonumber( new_args['count'] );
     local plain = new_args['plain'] or true;
     local plain = new_args['plain'] or true;
       
     if source_str == '' or pattern == '' then
     if source_str == '' or pattern == '' then
         return source_str;
         return source_str;
     end     
     end     
     plain = str._getBoolean( plain );
     plain = str._getBoolean( plain );
 
     if plain then
     if plain then
         pattern = str._escapePattern( pattern );
         pattern = str._escapePattern( pattern );
         replace = mw.ustring.gsub( replace, "%%", "%%%%" ); --Only need to escape replacement sequences.
         replace = mw.ustring.gsub( replace, "%%", "%%%%" ); --Only need to escape replacement sequences.
     end
     end
   
     local result;
     local result;
 
     if count ~= nil then
     if count ~= nil then
         result = mw.ustring.gsub( source_str, pattern, replace, count );
         result = mw.ustring.gsub( source_str, pattern, replace, count );
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         result = mw.ustring.gsub( source_str, pattern, replace );
         result = mw.ustring.gsub( source_str, pattern, replace );
     end         
     end         
 
     return result;
     return result;
end
end
 
--[[  
--[[  
     simple function to pipe string.rep to templates.
     simple function to pipe string.rep to templates.
]]
]]
 
function str.rep( frame )
function str.rep( frame )
     local repetitions = tonumber( frame.args[2] )
     local repetitions = tonumber( frame.args[2] )
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     return string.rep( frame.args[1] or '', repetitions )
     return string.rep( frame.args[1] or '', repetitions )
end
end
 
--[[
--[[
Helper function that populates the argument list given that user may need to use a mix of
Helper function that populates the argument list given that user may need to use a mix of
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     local index = 1;
     local index = 1;
     local value;
     local value;
   
     for i,arg in ipairs( arg_list ) do
     for i,arg in ipairs( arg_list ) do
         value = frame_args[arg]
         value = frame_args[arg]
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         new_args[arg] = value;
         new_args[arg] = value;
     end
     end
   
     return new_args;
     return new_args;
end         
end         
 
--[[
--[[
Helper function to handle error messages.
Helper function to handle error messages.
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     local ignore_errors = frame.args.ignore_errors or false;
     local ignore_errors = frame.args.ignore_errors or false;
     local no_category = frame.args.no_category or false;
     local no_category = frame.args.no_category or false;
   
     if str._getBoolean(ignore_errors) then
     if str._getBoolean(ignore_errors) then
         return '';
         return '';
     end
     end
   
     local error_str = '<strong class="error">String Module Error: ' .. error_str .. '</strong>';
     local error_str = '<strong class="error">String Module Error: ' .. error_str .. '</strong>';
     if error_category ~= '' and not str._getBoolean( no_category ) then
     if error_category ~= '' and not str._getBoolean( no_category ) then
         error_str = '[[Category:' .. error_category .. ']]' .. error_str;
         error_str = '[[Category:' .. error_category .. ']]' .. error_str;
     end         
     end         
   
     return error_str;
     return error_str;
end
end
 
--[[
--[[
Helper Function to interpret boolean strings
Helper Function to interpret boolean strings
Line 444: Line 445:
function str._getBoolean( boolean_str )
function str._getBoolean( boolean_str )
     local boolean_value;
     local boolean_value;
   
     if type( boolean_str ) == 'string' then
     if type( boolean_str ) == 'string' then
         boolean_str = boolean_str:lower();
         boolean_str = boolean_str:lower();
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     return boolean_value
     return boolean_value
end
end
 
--[[
--[[
Helper function that escapes all pattern characters so that they will be treated  
Helper function that escapes all pattern characters so that they will be treated  
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     return mw.ustring.gsub( pattern_str, "([%(%)%.%%%+%-%*%?%[%^%$%]])", "%%%1" );
     return mw.ustring.gsub( pattern_str, "([%(%)%.%%%+%-%*%?%[%^%$%]])", "%%%1" );
end
end
 
return str
return str
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