Module:LangSwitch - Revision history

Epìdosis: Try

2026-06-05T15:01:03Z

Try

← Older revision		Revision as of 15:01, 5 June 2026
Line 10:		Line 10:
	* User:Jarekt		* User:Jarekt
	]]		]]

	~~-- add optional module~~
	~~-- used for debugging purposes as it detects cases of unintended global variables~~
	~~require('strict')~~

	local p = {}		local p = {}
Line 28:		Line 24:
	args - table with translations by language		args - table with translations by language
	lang - desired language (often user's native language)		lang - desired language (often user's native language)

	Error Handling:		Error Handling:

	]]		]]
			local function defaultCheck(args)
	function ~~p._langSwitch~~(args~~, lang~~) ~~-- args: table of translations~~
	~~-- Return error if there is not default and no english version~~
	if not args.en and not args.default then		if not args.en and not args.default then
	local err = '<b class="error">LangSwitch Error: no default</b>'		local err = '<b class="error">LangSwitch Error: no default</b>'
Line 43:		Line 37:
	end		end
	end		end
			return false
	~~-- To improve performance try quick switch~~, ~~and load fallback chain only if needed.~~		end
	~~-- In the vast majority of cases fast switch is sufficient~~
	local ~~val~~ = args~~[lang]~~
	if ~~val~~ == '~' then		local function quickSwitch(args, arg)
	~~return~~ ''		local err = defaultCheck(args)
	~~elseif val and val ~= '' then~~		if err then
	return ~~val~~		return err
	~~elseif~~ args~~.quick~~ then		end
	return ~~nil~~		if arg == '~' then
			arg = ''
			end
			return arg
			end


			function p._langSwitch(args, lang) -- args: table of translations
			-- Return error if there is not default and no english version
			local err = defaultCheck(args)
			if err then
			return err
	end		end

	-- get the list of accepetable language (lang + those in lang's fallback chain) and check their content		-- get the list of accepetable language (lang + those in lang's fallback chain) and check their content
	assert(lang, 'LangSwitch Error: no lang')		assert(lang, 'LangSwitch Error: no lang')

			--local langList = {lang}
			--if not args[lang] then
	local langList = mw.language.getFallbacksFor(lang)		local langList = mw.language.getFallbacksFor(lang)
	table.insert(langList,1,lang)		table.insert(langList, 1, lang)
	table.insert(langList,math.max(#langList,2),'default')		table.insert(langList, math.max(#langList, 2), 'default')
	for _, language in ipairs(langList) do		--end
	~~val~~ = args[language]
	if ~~val~~ == '~' then		for _, language in ipairs(langList) do
			lang = args[language]
			if lang == '~' then
	return ''		return ''
	elseif ~~val~~ and ~~val~~ ~= '' then		elseif lang and lang ~= '' then
	return ~~val~~		return lang
	end		end
	end		end
Line 81:		Line 90:
	frame.args - table with translations by language		frame.args - table with translations by language
	frame.args.lang - desired language (often user's native language)		frame.args.lang - desired language (often user's native language)

	Error Handling:		Error Handling:

	]]		]]
	function p.langSwitch(frame) -- version to be used from wikitext		function p.langSwitch(frame) -- version to be used from wikitext
	local args = frame.args		local args = frame.args
	-- if no expected args provided than check parent template/module args		-- if no expected args provided than check parent template/module args
	if args.en==nil and args.default==nil and args.nocat==nil then		if args.en == nil and args.default == nil and args.nocat == nil then
	args = mw.getCurrentFrame():getParent().args		args = mw.getCurrentFrame():getParent().args
	end		end

	local lang = args.lang		local lang = args.lang
	if not lang or not mw.language.~~isKnownLanguageTag~~(lang) then		if not lang or not mw.language.isSupportedLanguage(lang) then
	lang = frame:callParserFunction( "int", "lang" ) -- get user's chosen language		lang = frame:callParserFunction("int", "lang") -- get user's chosen language
	end		end

	-- Try quick switch ~~which checks the most likely option when fallback is not needed~~		-- Try quick switch
	~~args.quick = true;~~		local args1 = args[lang]
	local ~~val~~ = ~~p._langSwitch(~~args, lang)		if args1 and args1 ~= '' then
	if ~~val~~ then		return quickSwitch(args, args1)
	return ~~val~~
	end		end

	-- Allow input in format: {{LangSwitch\|de=Grün\|es/it/pt=Verde\|fr=Vert\|en=Green \|lang=en}}		-- Allow input in format: {{LangSwitch\|de=Grün\|es/it/pt=Verde\|fr=Vert\|en=Green \|lang=en}}
	-- with multiple languages mapping to a single value		-- with multiple languages mapping to a single value
	~~local~~ args1 = {}		args1 = {}
	for name, value in pairs( args ) do		for name, value in pairs(args) do
	if value ~= '' and type(name)=='string' then		if value ~= '' and type(name) == 'string' then
	for str in string.gmatch( name, "([^/]+)" ) do		-- split multi keys
			for str in string.gmatch(name, "([^/]+)") do
	args1[str] = value		args1[str] = value
	end		end

Epìdosis: 1 revision imported: Import templates and modules from Wikidata

2026-06-03T17:15:02Z

1 revision imported: Import templates and modules from Wikidata

← Older revision		Revision as of 17:15, 3 June 2026
(No difference)

d>Legoktm: Replace Module:No globals with require( "strict" )

2022-11-17T23:40:35Z

Replace Module:No globals with require( "strict" )

New page

--[[
__ __ _ _ _ ____ _ _ _
| \/ | ___ __| |_ _| | ___ _| | __ _ _ __ __ _/ ___|_ _(_) |_ ___| |__
| |\/| |/ _ \ / _` | | | | |/ _ (_) | / _` | '_ \ / _` \___ \ \ /\ / / | __/ __| '_ \
| | | | (_) | (_| | |_| | | __/_| |__| (_| | | | | (_| |___) \ V V /| | || (__| | | |
|_| |_|\___/ \__,_|\__,_|_|\___(_)_____\__,_|_| |_|\__, |____/ \_/\_/ |_|\__\___|_| |_|
|___/
Authors and maintainers:
* User:Zolo - original version in Module:Fallback
* User:Jarekt
]]

-- add optional module
-- used for debugging purposes as it detects cases of unintended global variables
require('strict')

local p = {}

--[[
_langSwitch

This function is the core part of the LangSwitch template.

Example usage from Lua:
text = _langSwitch({en='text in english', pl='tekst po polsku'}, lang)

Parameters:
args - table with translations by language
lang - desired language (often user's native language)

Error Handling:

]]

function p._langSwitch(args, lang) -- args: table of translations
-- Return error if there is not default and no english version
if not args.en and not args.default then
local err = '<b class="error">LangSwitch Error: no default</b>'
if args.nocat == '1' then
return err
else
return err .. '[[Category:LangSwitch template without default version]]'
end
end

-- To improve performance try quick switch, and load fallback chain only if needed.
-- In the vast majority of cases fast switch is sufficient
local val = args[lang]
if val == '~' then
return ''
elseif val and val ~= '' then
return val
elseif args.quick then
return nil
end

-- get the list of accepetable language (lang + those in lang's fallback chain) and check their content
assert(lang, 'LangSwitch Error: no lang')
local langList = mw.language.getFallbacksFor(lang)
table.insert(langList,1,lang)
table.insert(langList,math.max(#langList,2),'default')
for _, language in ipairs(langList) do
val = args[language]
if val == '~' then
return ''
elseif val and val ~= '' then
return val
end
end
end

--[[
langSwitch

This function is the core part of the LangSwitch template.

Example Usage from a template:
{{#invoke:fallback|langSwitch|en=text in english|pl=tekst po polsku|lang={{int:lang}} }}

Parameters:
frame.args - table with translations by language
frame.args.lang - desired language (often user's native language)

Error Handling:

]]
function p.langSwitch(frame) -- version to be used from wikitext
local args = frame.args
-- if no expected args provided than check parent template/module args
if args.en==nil and args.default==nil and args.nocat==nil then
args = mw.getCurrentFrame():getParent().args
end
local lang = args.lang
if not lang or not mw.language.isKnownLanguageTag(lang) then
lang = frame:callParserFunction( "int", "lang" ) -- get user's chosen language
end

-- Try quick switch which checks the most likely option when fallback is not needed
args.quick = true;
local val = p._langSwitch(args, lang)
if val then
return val
end

-- Allow input in format: {{LangSwitch|de=Grün|es/it/pt=Verde|fr=Vert|en=Green |lang=en}}
-- with multiple languages mapping to a single value
local args1 = {}
for name, value in pairs( args ) do
if value ~= '' and type(name)=='string' then
for str in string.gmatch( name, "([^/]+)" ) do
args1[str] = value
end
end
end
return p._langSwitch(args1, lang)
end

return p