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