Module:String

[] [] []

Info

Documentation del modulo

Iste modulo forni functionalitate basic pro manipular catenas de characteres (strings).

Le major parte del functiones fornite hic pote esser invocate con parametros a nomine, parametros sin nomine, o un mixtura de illos. De parametros a nomine, MediaWiki removera automaticamente le spatios blanc initial o final. Dependente del uso intendite, conservar o remover le spatio blanc pote esser avantagiose.

Optiones global

ignore_errors

Si 'true' o 1, un error produce un catena vacue in loco de un message de error.

error_category

Si un error occurre, specifica le nomine de un categoria a includer con le message de error. Le categoria predefinite es Categoria:Errors reported by Module String.

no_category

Si 'true' o 1, nulle categoria essera addite si un error se produce.

len

Iste function retorna le longitude de un catena.

Usage:

{{#invoke:String|len|catena_a_tractar}}

O

{{#invoke:String|len|s= catena_a_tractar }}

Parametros:

s

Le catena cuje longitude reportar

sub

Iste function retorna un subcatena de un catena a base del indices specificate.

Usage:

{{#invoke:String|sub|catena_a_tractar|position_de_initio|position_de_fin}}

OR

{{#invoke:String|sub|s= catena_a_tractar |i= position_de_initio |j= position_de_fin }}

Parametros:

s

Le catena del qual retornar un subcatena

i

Le prime indice del subcatena a retornar, predefinite a 1.

j

Le ultime indice del subcatena a retornar, predefinite al ultime character.

Le prime character del catena ha un indice de 1, le secunde de 2, le tertie de 3, etc. Si i o j ha un valor negative, selige un character a partir del fin del catena. Per exemplo, un valor de -1 selige le ultime character del catena, -2 le penultime, -3 le antepenultime, etc.

Si un indice excede le dimension del catena, un error se produce.

match

Iste function retorna un subcatena ab le catena de origine que corresponde a un expression regular specificate.

Usage:

{{#invoke:String|match|catena_de_fonte|expression_regular|position_de_initio|numero_del_correspondentia|marcator_de_texto_simple|sortita_si_necun_correspondentia}}

OR

{{#invoke:String|match|s= catena_de_fonte |pattern= expression_regular |start= position_de_initio|match= numero_del_correspondentia|plain= marcator_de_texto_simple |nomatch= sortita_si_necun_correspondentia }}

Parameters:

s

Le catena in le qual cercar

pattern

Le expression o catena a cercar intra le catena

start

Le indice intra le catena de origine al qual comenciar a cercar. Le prime character del catena ha le indice 1. Predefinite a 1.

match

In alcun casos es possibile cercar un sol catena plure vices. Isto specifica le resultato a retornar, ubi le prime resultato es match= 1. Si un numero negative es specificate, un resultato se retorna a partir del ultime resultato. Per exemplo, match = -1 requesta le ultime resultato. Predefinite a 1.

plain

Valor boolean indicante que le expression debe esser interpretate como texto simple e non como un expression regular de stilo Lua. Predefinite a false (pro cambiar lo: plain=true)

nomatch

Si nulle resultato se produce, scribe le valor de "nomatch" in loco de un message de error.

Si le numero_del_correspondentia or position_de_initio excede le dimension del catena a cercar, o si nulle resultato es trovate, un error se produce. Le parametro ignore_errors=true supprime omne message de error e un catena vacue se retorna in su loco.

Pro information sur construer expressiones regular de Lua, vide:

• Scribunto patterns
• Scribunto Unicode string patterns

pos

Iste function retorna un character singule ab le catena al position pos.

Usage:

{{#invoke:String|pos|catena_a_tractar|valor_de_indice}}

O

{{#invoke:String|pos|target= catena_a_tractar |pos= valor_de_indice }}

Parametros:

target

Le catena a cercar

pos

Le indice del character a retornar

Le prime character ha un indice de 1.

Un valor negative selige un character a partir del fin del catena. Per exemplo, pos = -1 selige le ultime character.

Un valor de zero, o que excede le dimension del catena, produce un error.

find

Iste function permitte cercar un catena o expression intra un altere catena.

Usage:

{{#invoke:String|find|catena_de_origine|catena_a_tractar|position_de_initio|marcator_de_texto_simple}}

O

{{#invoke:String|find|source= catena_de_origine |target= target_str |start= position_de_initio|plain= marcator_de_texto_simple }}

Parametros:

source

Le catena a cercar

target

Le catena o expression a trovar intra source

start

Le indice in source pro comenciar le recerca, predefinite a 1

plain

Valor boolean indicante que le expression debe esser interpretate como texto simple e non como un expression regular de stilo Lua. Predefinite a true

Iste function retorna le prime indice >= "start" ubi "target" pote esser trovate intra "source". Le indices ha un base de 1. Si "target" non es trovate, o si "source" o "target" manca o es vacue, iste function retorna 0.

Iste function deberea esser secur pro catenas a codification UTF-8.

replace

Iste function permitte reimplaciar un catena o expression intra un altere catena.

Usage:

{{#invoke:String|replace|catena_de_origine|expression_regular|catena_a_reimplaciar|numero_de_reimplaciamentos|marcator_de_texto_simple}}

O

{{#invoke:String|replace|source= catena_de_fonte |pattern= expression_regular|replace= catena_a_reimplaciar |count= numero_de_reimplaciamentos |plain= marcator_de_texto_simple }}

Parametros:

source

Le catena a cercar

pattern

Le catena o patrono a cercar intra source

replace

Le texto a reimplaciar

count

Le numero de occurrentias a reimplaciar; predefinite a all (totes)

plain

Valor boolean indicante que le expression debe esser interpretate como texto simple e non como un expression ustring de Scribunto (un expression regular de stilo Lua apte pro Unicode). Predefinite a true

rep

Repete un catena n vices. Un function simple pro connecter catena.rep a patronos. Usage:

{{#invoke:String|rep|origine|numero}}

Parametros:

origine

Le catena a repeter

numero

Le numero de repetitiones

Exemplo: {{#invoke:String|rep|hello|3}} da hellohellohello

Nota

Iste documentation contine material traducite ab Wikipedia in anglese. Le texto original se trova in le version 773625196 de en:Module:String/doc, e es usate secundo le mandatos del licentia respective.

Nota

Iste modulo contine codice adaptate e traducite ab Wikipedia in anglese. Le codice original se trova in le version 1305419441 de en:Module:String, e es usate secundo le mandatos del licentia respective.

--[[

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 first 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 {{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. It is exported for use in other modules

Usage:
strmatch = require("Module:String")._match
sresult = strmatch( s, pattern, start, match, plain, nomatch )

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.

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 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

--[[
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
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 {{str_find}}, 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 = string.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

-- findpagetext returns the position of a piece of text in a page
-- First positional parameter or |text is the search text
-- Optional parameter |title is the page title, defaults to current page
-- Optional parameter |plain is either true for plain search (default) or false for Lua pattern search
-- Optional parameter |nomatch is the return value when no match is found; default is nil
function str._findpagetext(args)
	-- process parameters
	local nomatch = args.nomatch or ""
	if nomatch == "" then nomatch = nil end
	--
	local text = mw.text.trim(args[1] or args.text or "")
	if text == "" then return nil end
	--
	local title = args.title or ""
	local titleobj
	if title == "" then
		titleobj = mw.title.getCurrentTitle()
	else
		titleobj = mw.title.new(title)
	end
	--
	local plain = args.plain or ""
	if plain:sub(1, 1) == "f" then plain = false else plain = true end
	-- get the page content and look for 'text' - return position or nomatch
	local content = titleobj and titleobj:getContent()
	return content and mw.ustring.find(content, text, 1, plain) or nomatch
end
function str.findpagetext(frame)
	local args = frame.args
	local pargs = frame:getParent().args
	for k, v in pairs(pargs) do
		args[k] = v
	end
	if not (args[1] or args.text) then return nil end
	-- just the first value
	return (str._findpagetext(args))
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 = '<strong class="error">String Module Error: ' .. error_str .. '</strong>'
	if error_category ~= '' and not str._getBoolean( no_category ) then
		error_str = '[[Category:' .. error_category .. ']]' .. 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 ( string.gsub( pattern_str, "[%(%)%.%%%+%-%*%?%[%^%$%]]", "%%%0" ) )
end

return str