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Zeile 10: Zeile 10:
  
 
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.
Zeile 36: Zeile 36:
  
 
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
Zeile 42: Zeile 42:
 
]]
 
]]
 
function str.len( frame )
 
function str.len( frame )
local new_args = str._getParameters( frame.args, {'s'} );
+
local new_args = str._getParameters( frame.args, {'s'} )
local s = new_args['s'] or '';
+
local s = new_args['s'] or ''
 
return mw.ustring.len( s )
 
return mw.ustring.len( s )
 
end
 
end
Zeile 58: Zeile 58:
  
 
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
Zeile 71: Zeile 71:
 
]]
 
]]
 
function str.sub( frame )
 
function str.sub( frame )
local new_args = str._getParameters( frame.args, { 's', 'i', 'j' } );
+
local new_args = str._getParameters( frame.args, { 's', 'i', 'j' } )
local s = new_args['s'] or '';
+
local s = new_args['s'] or ''
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
i = len + i + 1;
+
i = len + i + 1
 
end
 
end
 
if j < 0 then
 
if j < 0 then
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' )
 
end
 
end
 
if j < i then
 
if j < i then
return str._error( 'String subset indices out of order' );
+
return str._error( 'String subset indices out of order' )
 
end
 
end
  
Zeile 115: Zeile 115:
 
{{#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}}
 
OR
 
OR
{{#invoke:String|pos|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
    pattern: The pattern or string to find within the string
+
pattern: The pattern or string to find within the string
    start: The index within the source string to start the search.  The first
+
start: The index within the source string to start the search.  The first
        character of the string has index 1.  Defaults to 1.
+
character of the string has index 1.  Defaults to 1.
    match: In some cases it may be possible to make multiple matches on a single
+
match: In some cases it may be possible to make multiple matches on a single
        string.  This specifies which match to return, where the first match is
+
string.  This specifies which match to return, where the first match is
        match= 1.  If a negative number is specified then a match is returned
+
match= 1.  If a negative number is specified then a match is returned
        counting from the last match.  Hence match = -1 is the same as requesting
+
counting from the last match.  Hence match = -1 is the same as requesting
        the last match.  Defaults to 1.
+
the last match.  Defaults to 1.
    plain: A flag indicating that the pattern should be understood as plain
+
plain: A flag indicating that the pattern should be understood as plain
        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
Zeile 143: Zeile 143:
 
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
  
 
]]
 
]]
 
-- This sub-routine is exported for use in other modules
 
-- This sub-routine is exported for use in other modules
function str._match( s, pattern, start, match_index, plain, nomatch )
+
function str._match( s, pattern, start, match_index, plain_flag, nomatch )
 
if s == '' then
 
if s == '' then
return str._error( 'Target string is empty' );
+
return str._error( 'Target string is empty' )
 
end
 
end
 
if pattern == '' then
 
if pattern == '' then
return str._error( 'Pattern string is empty' );
+
return str._error( 'Pattern string is empty' )
 
end
 
end
 
start = tonumber(start) or 1
 
start = tonumber(start) or 1
 
if math.abs(start) < 1 or math.abs(start) > mw.ustring.len( s ) then
 
if math.abs(start) < 1 or math.abs(start) > mw.ustring.len( s ) then
return str._error( 'Requested start is out of range' );
+
return str._error( 'Requested start is out of range' )
 
end
 
end
 
if match_index == 0 then
 
if match_index == 0 then
return str._error( 'Match index is out of range' );
+
return str._error( 'Match index is out of range' )
 
end
 
end
 
if plain_flag then
 
if plain_flag then
pattern = str._escapePattern( pattern );
+
pattern = str._escapePattern( pattern )
 
end
 
end
  
Zeile 173: Zeile 173:
 
else
 
else
 
if start > 1 then
 
if start > 1 then
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
 
-- Forward search
 
-- Forward search
 
for w in iterator do
 
for w in iterator do
match_index = match_index - 1;
+
match_index = match_index - 1
 
if match_index == 0 then
 
if match_index == 0 then
result = w;
+
result = w
break;
+
break
 
end
 
end
 
end
 
end
 
else
 
else
 
-- Reverse search
 
-- Reverse search
local result_table = {};
+
local result_table = {}
local count = 1;
+
local count = 1
 
for w in iterator do
 
for w in iterator do
result_table[count] = w;
+
result_table[count] = w
count = count + 1;
+
count = count + 1
 
end
 
end
  
result = result_table[ count + match_index ];
+
result = result_table[ count + match_index ]
 
end
 
end
 
end
 
end
Zeile 201: Zeile 201:
 
if result == nil then
 
if result == nil then
 
if nomatch == nil then
 
if nomatch == nil then
return str._error( 'Match not found' );
+
return str._error( 'Match not found' )
 
else
 
else
return nomatch;
+
return nomatch
 
end
 
end
 
else
 
else
return result;
+
return result
 
end
 
end
 
end
 
end
 
-- This is the entry point for #invoke:String|match
 
-- This is the entry point for #invoke:String|match
 
function str.match( frame )
 
function str.match( frame )
local new_args = str._getParameters( frame.args, {'s', 'pattern', 'start', 'match', 'plain', 'nomatch'} );
+
local new_args = str._getParameters( frame.args, {'s', 'pattern', 'start', 'match', 'plain', 'nomatch'} )
local s = new_args['s'] or '';
+
local s = new_args['s'] or ''
local start = tonumber( new_args['start'] ) or 1;
+
local start = tonumber( new_args['start'] ) or 1
local plain_flag = str._getBoolean( new_args['plain'] or false );
+
local plain_flag = str._getBoolean( new_args['plain'] or false )
local pattern = new_args['pattern'] or '';
+
local pattern = new_args['pattern'] or ''
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']
  
return str._match( s, pattern, start, match_index, plain, nomatch )
+
return str._match( s, pattern, start, match_index, plain_flag, nomatch )
 
end
 
end
  
Zeile 233: Zeile 233:
  
 
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
Zeile 248: Zeile 248:
 
]]
 
]]
 
function str.pos( frame )
 
function str.pos( frame )
local new_args = str._getParameters( frame.args, {'target', 'pos'} );
+
local new_args = str._getParameters( frame.args, {'target', 'pos'} )
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
  
Zeile 274: Zeile 274:
 
]]
 
]]
 
function str.str_find( frame )
 
function str.str_find( frame )
local new_args = str._getParameters( frame.args, {'source', 'target'} );
+
local new_args = str._getParameters( frame.args, {'source', 'target'} )
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
  
Zeile 302: Zeile 302:
  
 
Parameters
 
Parameters
    source: The string to search
+
source: The string to search
    target: The string or pattern to find within source
+
target: The string or pattern to find within source
    start: The index within the source string to start the search, defaults to 1
+
start: The index within the source string to start the search, defaults to 1
    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
Zeile 320: Zeile 320:
 
]]
 
]]
 
function str.find( frame )
 
function str.find( frame )
local new_args = str._getParameters( frame.args, {'source', 'target', 'start', 'plain' } );
+
local new_args = str._getParameters( frame.args, {'source', 'target', 'start', 'plain' } )
local source_str = new_args['source'] or '';
+
local source_str = new_args['source'] or ''
local pattern = new_args['target'] or '';
+
local pattern = new_args['target'] or ''
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 )
Zeile 353: Zeile 353:
  
 
Parameters
 
Parameters
    source: The string to search
+
source: The string to search
    pattern: The string or pattern to find within source
+
pattern: The string or pattern to find within source
    replace: The replacement text
+
replace: The replacement text
    count: The number of occurences to replace, defaults to all.
+
count: The number of occurences to replace, defaults to all.
    plain: Boolean flag indicating that pattern should be understood as plain
+
plain: Boolean flag indicating that pattern 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
 
]]
 
]]
 
function str.replace( frame )
 
function str.replace( frame )
local new_args = str._getParameters( frame.args, {'source', 'pattern', 'replace', 'count', 'plain' } );
+
local new_args = str._getParameters( frame.args, {'source', 'pattern', 'replace', 'count', 'plain' } )
local source_str = new_args['source'] or '';
+
local source_str = new_args['source'] or ''
local pattern = new_args['pattern'] or '';
+
local pattern = new_args['pattern'] or ''
local replace = new_args['replace'] or '';
+
local replace = new_args['replace'] or ''
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 )
 
else
 
else
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] )
Zeile 413: Zeile 412:
  
 
Parameters
 
Parameters
    pattern_string: The pattern string to escape.
+
pattern_string: The pattern string to escape.
 
]]
 
]]
 
function str.escapePattern( frame )
 
function str.escapePattern( frame )
 
local pattern_str = frame.args[1]
 
local pattern_str = frame.args[1]
 
if not pattern_str then
 
if not pattern_str then
return str._error( 'No pattern string specified' );
+
return str._error( 'No pattern string specified' )
 
end
 
end
 
local result = str._escapePattern( pattern_str )
 
local result = str._escapePattern( pattern_str )
 
return result
 
return result
 +
end
 +
 +
--[[
 +
count
 +
This function counts the number of occurrences of one string in another.
 +
]]
 +
function str.count(frame)
 +
local args = str._getParameters(frame.args, {'source', 'pattern', 'plain'})
 +
local source = args.source or ''
 +
local pattern = args.pattern or ''
 +
local plain = str._getBoolean(args.plain or true)
 +
if plain then
 +
pattern = str._escapePattern(pattern)
 +
end
 +
local _, count = mw.ustring.gsub(source, pattern, '')
 +
return count
 +
end
 +
 +
--[[
 +
endswith
 +
This function determines whether a string ends with another string.
 +
]]
 +
function str.endswith(frame)
 +
local args = str._getParameters(frame.args, {'source', 'pattern'})
 +
local source = args.source or ''
 +
local pattern = args.pattern or ''
 +
if pattern == '' then
 +
-- All strings end with the empty string.
 +
return "yes"
 +
end
 +
if mw.ustring.sub(source, -mw.ustring.len(pattern), -1) == pattern then
 +
return "yes"
 +
else
 +
return ""
 +
end
 +
end
 +
 +
--[[
 +
join
 +
 +
Join all non empty arguments together; the first argument is the separator.
 +
Usage:
 +
{{#invoke:String|join|sep|one|two|three}}
 +
]]
 +
function str.join(frame)
 +
local args = {}
 +
local sep
 +
for _, v in ipairs( frame.args ) do
 +
if sep then
 +
if v ~= '' then
 +
table.insert(args, v)
 +
end
 +
else
 +
sep = v
 +
end
 +
end
 +
return table.concat( args, sep or '' )
 
end
 
end
  
Zeile 431: Zeile 487:
 
]]
 
]]
 
function str._getParameters( frame_args, arg_list )
 
function str._getParameters( frame_args, arg_list )
local new_args = {};
+
local new_args = {}
local index = 1;
+
local index = 1
local value;
+
local value
  
for i,arg in ipairs( arg_list ) do
+
for _, arg in ipairs( arg_list ) do
 
value = frame_args[arg]
 
value = frame_args[arg]
 
if value == nil then
 
if value == nil then
value = frame_args[index];
+
value = frame_args[index]
index = index + 1;
+
index = index + 1
 
end
 
end
new_args[arg] = value;
+
new_args[arg] = value
 
end
 
end
  
return new_args;
+
return new_args
 
end
 
end
  
Zeile 451: Zeile 507:
 
]]
 
]]
 
function str._error( error_str )
 
function str._error( error_str )
local frame = mw.getCurrentFrame();
+
local frame = mw.getCurrentFrame()
local error_category = frame.args.error_category or 'Errors reported by Module String';
+
local error_category = frame.args.error_category or 'Errors reported by Module String'
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
  
Zeile 472: Zeile 528:
 
]]
 
]]
 
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()
 
if boolean_str == 'false' or boolean_str == 'no' or boolean_str == '0'
 
if boolean_str == 'false' or boolean_str == 'no' or boolean_str == '0'
 
or boolean_str == '' then
 
or boolean_str == '' then
boolean_value = false;
+
boolean_value = false
 
else
 
else
boolean_value = true;
+
boolean_value = true
 
end
 
end
 
elseif type( boolean_str ) == 'boolean' then
 
elseif type( boolean_str ) == 'boolean' then
boolean_value = boolean_str;
+
boolean_value = boolean_str
 
else
 
else
error( 'No boolean value found' );
+
error( 'No boolean value found' )
 
end
 
end
 
return boolean_value
 
return boolean_value
Zeile 495: Zeile 551:
 
]]
 
]]
 
function str._escapePattern( pattern_str )
 
function str._escapePattern( pattern_str )
return mw.ustring.gsub( pattern_str, "([%(%)%.%%%+%-%*%?%[%^%$%]])", "%%%1" );
+
return mw.ustring.gsub( pattern_str, "([%(%)%.%%%+%-%*%?%[%^%$%]])", "%%%1" )
 +
end
 +
 
 +
--[[
 +
check if string is a number
 +
]]
 +
function str.isNumber( frame )
 +
if not tonumber( frame.args[1] ) then
 +
return 0
 +
else
 +
return 1
 +
end
 
end
 
end
  
 
return str
 
return str

Aktuelle Version vom 9. November 2019, 11:47 Uhr

--[[

This module is intended to provide access to basic string functions.

Most of the functions provided here can be invoked with named parameters, unnamed parameters, or a mixture. If named parameters are used, Mediawiki will automatically remove any leading or trailing whitespace from the parameter. Depending on the intended use, it may be advantageous to either preserve or remove such whitespace.

Global options ignore_errors: If set to 'true' or 1, any error condition will result in an empty string being returned rather than an error message.

error_category: If an error occurs, specifies the name of a category to include with the error message. The default category is [Category:Errors reported by Module String].

no_category: If set to 'true' or 1, no category will be added if an error is generated.

Unit tests for this module are available at Module:String/tests. ]]

local str = {}

--[[ len

This function returns the length of the target string.

Usage: {{#invoke:String|len|target_string|}} OR {{#invoke:String|len|s=target_string}}

Parameters s: The string whose length to report

If invoked using named parameters, Mediawiki will automatically remove any leading or trailing whitespace from the target string. ]] function str.len( frame ) local new_args = str._getParameters( frame.args, {'s'} ) local s = new_args['s'] or return mw.ustring.len( s ) end

--[[ sub

This function returns a substring of the target string at specified indices.

Usage: {{#invoke:String|sub|target_string|start_index|end_index}} OR {{#invoke:String|sub|s=target_string|i=start_index|j=end_index}}

Parameters s: The string to return a subset of 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.

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 counting from the end of the string. Hence, a value of -1 is the same as selecting the last character of the string.

If the requested indices are out of range for the given string, an error is reported. ]] function str.sub( frame ) local new_args = str._getParameters( frame.args, { 's', 'i', 'j' } ) local s = new_args['s'] or local i = tonumber( new_args['i'] ) or 1 local j = tonumber( new_args['j'] ) or -1

local len = mw.ustring.len( s )

-- Convert negatives for range checking if i < 0 then i = len + i + 1 end if j < 0 then j = len + j + 1 end

if i > len or j > len or i < 1 or j < 1 then return str._error( 'String subset index out of range' ) end if j < i then return str._error( 'String subset indices out of order' ) end

return mw.ustring.sub( s, i, j ) end

--[[ This function implements that features of Vorlage:Str sub old and is kept in order to maintain these older templates. ]] function str.sublength( frame ) local i = tonumber( frame.args.i ) or 0 local len = tonumber( frame.args.len ) return mw.ustring.sub( frame.args.s, i + 1, len and ( i + len ) ) end

--[[ match

This function returns a substring from the source string that matches a specified pattern.

Usage: {{#invoke:String|match|source_string|pattern_string|start_index|match_number|plain_flag|nomatch_output}} OR {{#invoke:String|match|s=source_string|pattern=pattern_string|start=start_index |match=match_number|plain=plain_flag|nomatch=nomatch_output}}

Parameters s: The string to search pattern: The pattern or string to find within the string start: The index within the source string to start the search. The first character of the string has index 1. Defaults to 1. match: In some cases it may be possible to make multiple matches on a single string. This specifies which match to return, where the first match is match= 1. If a negative number is specified then a match is returned counting from the last match. Hence match = -1 is the same as requesting the last match. Defaults to 1. plain: A flag indicating that the pattern should be understood as plain text. Defaults to false. 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 trailing whitespace from each string. In some circumstances this is desirable, in 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 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 an empty string will be returned on any failure.

For information on constructing Lua patterns, a form of [regular expression], see:

]] -- This sub-routine is exported for use in other modules function str._match( s, pattern, start, match_index, plain_flag, nomatch ) if s == then return str._error( 'Target string is empty' ) end if pattern == then return str._error( 'Pattern string is empty' ) end start = tonumber(start) or 1 if math.abs(start) < 1 or math.abs(start) > mw.ustring.len( s ) then return str._error( 'Requested start is out of range' ) end if match_index == 0 then return str._error( 'Match index is out of range' ) end if plain_flag then pattern = str._escapePattern( pattern ) end

local result if match_index == 1 then -- Find first match is simple case result = mw.ustring.match( s, pattern, start ) else if start > 1 then s = mw.ustring.sub( s, start ) end

local iterator = mw.ustring.gmatch(s, pattern) if match_index > 0 then -- Forward search for w in iterator do match_index = match_index - 1 if match_index == 0 then result = w break end end else -- Reverse search local result_table = {} local count = 1 for w in iterator do result_table[count] = w count = count + 1 end

result = result_table[ count + match_index ] end end

if result == nil then if nomatch == nil then return str._error( 'Match not found' ) else return nomatch end else return result end end -- This is the entry point for #invoke:String|match function str.match( frame ) local new_args = str._getParameters( frame.args, {'s', 'pattern', 'start', 'match', 'plain', 'nomatch'} ) local s = new_args['s'] or local start = tonumber( new_args['start'] ) or 1 local plain_flag = str._getBoolean( new_args['plain'] or false ) local pattern = new_args['pattern'] or local match_index = math.floor( tonumber(new_args['match']) or 1 ) local nomatch = new_args['nomatch']

return str._match( s, pattern, start, match_index, plain_flag, nomatch ) end

--[[ pos

This function returns a single character from the target string at position pos.

Usage: {{#invoke:String|pos|target_string|index_value}} OR {{#invoke:String|pos|target=target_string|pos=index_value}}

Parameters target: The string to search pos: The index for the character to return

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 other cases one may want to preserve the whitespace.

The first character has an index value of 1.

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.

A requested value of zero, or a value greater than the length of the string returns an error. ]] function str.pos( frame ) local new_args = str._getParameters( frame.args, {'target', 'pos'} ) local target_str = new_args['target'] or local pos = tonumber( new_args['pos'] ) or 0

if pos == 0 or math.abs(pos) > mw.ustring.len( target_str ) then return str._error( 'String index out of range' ) end

return mw.ustring.sub( target_str, pos, pos ) end

--[[ str_find

This function duplicates the behavior of {{#invoke:Str|find|{{{1}}}|{{{2}}}}}, including all of its quirks. 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.

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".

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 separatetly. ]] function str.str_find( frame ) local new_args = str._getParameters( frame.args, {'source', 'target'} ) local source_str = new_args['source'] or local target_str = new_args['target'] or

if target_str == then return 1 end

local start = mw.ustring.find( source_str, target_str, 1, true ) if start == nil then start = -1 end

return start end

--[[ find

This function allows one to search for a target string or pattern within another string.

Usage: {{#invoke:String|find|source_str|target_string|start_index|plain_flag}} OR {{#invoke:String|find|source=source_str|target=target_str|start=start_index|plain=plain_flag}}

Parameters source: The string to search target: The string or pattern to find within source start: The index within the source string to start the search, defaults to 1 plain: Boolean flag indicating that target should be understood as plain text and not as a Lua style regular expression, defaults to true

If invoked using named parameters, Mediawiki will automatically remove any leading or trailing whitespace from the parameter. In some circumstances this is desirable, in other cases one may want to preserve the whitespace.

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 function returns 0. If either "source" or "target" are missing / empty, this function also returns 0.

This function should be safe for UTF-8 strings. ]] function str.find( frame ) local new_args = str._getParameters( frame.args, {'source', 'target', 'start', 'plain' } ) local source_str = new_args['source'] or local pattern = new_args['target'] or local start_pos = tonumber(new_args['start']) or 1 local plain = new_args['plain'] or true

if source_str == or pattern == then return 0 end

plain = str._getBoolean( plain )

local start = mw.ustring.find( source_str, pattern, start_pos, plain ) if start == nil then start = 0 end

return start end

--[[ replace

This function allows one to replace a target string or pattern within another string.

Usage: {{#invoke:String|replace|source_str|pattern_string|replace_string|replacement_count|plain_flag}} OR {{#invoke:String|replace|source=source_string|pattern=pattern_string|replace=replace_string|

  count=replacement_count|plain=plain_flag}}

Parameters source: The string to search pattern: The string or pattern to find within source replace: The replacement text count: The number of occurences to replace, defaults to all. plain: Boolean flag indicating that pattern should be understood as plain text and not as a Lua style regular expression, defaults to true ]] function str.replace( frame ) local new_args = str._getParameters( frame.args, {'source', 'pattern', 'replace', 'count', 'plain' } ) local source_str = new_args['source'] or local pattern = new_args['pattern'] or local replace = new_args['replace'] or local count = tonumber( new_args['count'] ) local plain = new_args['plain'] or true

if source_str == or pattern == then return source_str end plain = str._getBoolean( plain )

if plain then pattern = str._escapePattern( pattern ) replace = mw.ustring.gsub( replace, "%%", "%%%%" ) --Only need to escape replacement sequences. end

local result

if count ~= nil then result = mw.ustring.gsub( source_str, pattern, replace, count ) else result = mw.ustring.gsub( source_str, pattern, replace ) end

return result end

--[[ simple function to pipe string.rep to templates. ]] function str.rep( frame ) local repetitions = tonumber( frame.args[2] ) if not repetitions then return str._error( 'function rep expects a number as second parameter, received "' .. ( frame.args[2] or ) .. '"' ) end return string.rep( frame.args[1] or , repetitions ) end

--[[ escapePattern

This function escapes special characters from a Lua string pattern. See [1] for details on how patterns work.

[1] https://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Patterns

Usage: {{#invoke:String|escapePattern|pattern_string}}

Parameters pattern_string: The pattern string to escape. ]] function str.escapePattern( frame ) local pattern_str = frame.args[1] if not pattern_str then return str._error( 'No pattern string specified' ) end local result = str._escapePattern( pattern_str ) return result end

--[[ count This function counts the number of occurrences of one string in another. ]] function str.count(frame) local args = str._getParameters(frame.args, {'source', 'pattern', 'plain'}) local source = args.source or local pattern = args.pattern or local plain = str._getBoolean(args.plain or true) if plain then pattern = str._escapePattern(pattern) end local _, count = mw.ustring.gsub(source, pattern, ) return count end

--[[ endswith This function determines whether a string ends with another string. ]] function str.endswith(frame) local args = str._getParameters(frame.args, {'source', 'pattern'}) local source = args.source or local pattern = args.pattern or if pattern == then -- All strings end with the empty string. return "yes" end if mw.ustring.sub(source, -mw.ustring.len(pattern), -1) == pattern then return "yes" else return "" end end

--[[ join

Join all non empty arguments together; the first argument is the separator. Usage: {{#invoke:String|join|sep|one|two|three}} ]] function str.join(frame) local args = {} local sep for _, v in ipairs( frame.args ) do if sep then if v ~= then table.insert(args, v) end else sep = v end end return table.concat( args, sep or ) end

--[[ Helper function that populates the argument list given that user may need to use a mix of named and unnamed parameters. This is relevant because named parameters are not identical to unnamed parameters due to string trimming, and when dealing with strings we sometimes want to either preserve or remove that whitespace depending on the application. ]] function str._getParameters( frame_args, arg_list ) local new_args = {} local index = 1 local value

for _, arg in ipairs( arg_list ) do value = frame_args[arg] if value == nil then value = frame_args[index] index = index + 1 end new_args[arg] = value end

return new_args end

--[[ Helper function to handle error messages. ]] function str._error( error_str ) local frame = mw.getCurrentFrame() local error_category = frame.args.error_category or 'Errors reported by Module String' local ignore_errors = frame.args.ignore_errors or false local no_category = frame.args.no_category or false

if str._getBoolean(ignore_errors) then return end

local error_str = 'String Module Error: ' .. error_str .. '' if error_category ~= and not str._getBoolean( no_category ) then error_str = .. error_str end

return error_str end

--[[ Helper Function to interpret boolean strings ]] function str._getBoolean( boolean_str ) local boolean_value

if type( boolean_str ) == 'string' then boolean_str = boolean_str:lower() if boolean_str == 'false' or boolean_str == 'no' or boolean_str == '0' or boolean_str == then boolean_value = false else boolean_value = true end elseif type( boolean_str ) == 'boolean' then boolean_value = boolean_str else error( 'No boolean value found' ) end return boolean_value end

--[[ Helper function that escapes all pattern characters so that they will be treated as plain text. ]] function str._escapePattern( pattern_str ) return mw.ustring.gsub( pattern_str, "([%(%)%.%%%+%-%*%?%[%^%$%]])", "%%%1" ) end

--[[ check if string is a number ]] function str.isNumber( frame ) if not tonumber( frame.args[1] ) then return 0 else return 1 end end

return str