Module:String: Difference between revisions

1,365 bytes removed ,  6 January 2021
Created page with "--[[ 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..."
w>RexxS
(separate annotations for str.match from those for str._match)
 
[[Templates]]>ISUtahraptor
(Created page with "--[[ 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...")
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--[[
--[[
_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. It is exported for use in other modules
specified pattern.


Usage:
Usage:
strmatch = require("Module:String")._match
{{#invoke:String|match|source_string|pattern_string|start_index|match_number|plain_flag|nomatch_output}}
sresult = strmatch( s, pattern, start, match, plain, nomatch )
OR
{{#invoke:String|match|s=source_string|pattern=pattern_string|start=start_index
    |match=match_number|plain=plain_flag|nomatch=nomatch_output}}


Parameters
Parameters
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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
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:
For information on constructing Lua patterns, a form of [regular expression], see:
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end
end
end
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:
* http://www.lua.org/manual/5.1/manual.html#5.4.1
* http://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Patterns
* http://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Ustring_patterns
]]
-- 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 )