Module:Fallback

-- \/  | ___   __| |_   _| | ___ _|  ___|_ _| | | |__   __ _  ___| | __ | |\/| |/ _ \ / _` | | | | |/ _ (_) |_ / _` | | | '_ \ / _` |/ __| |/ / | |  | | (_) | (_| | |_| | |  __/_|  _| (_| | | | |_) | (_| | (__|   <  |_|  |_|\___/ \__,_|\__,_|_|\___(_)_|  \__,_|_|_|_.__/ \__,_|\___|_|\_\ Authors and maintainers:
 * User:Zolo  - original version
 * User:Jarekt

local function normalize_input_args(input_args, output_args) for name, value in pairs(input_args) do		if value ~= '' then -- nuke empty strings if type(name) == 'string' then name = string.lower(name) end -- convert to lower case output_args[name] = value end end return output_args end

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 = ' LangSwitch Error: no default ' if args.nocat ~= '1' then err = err..'' return err end 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		if args[language] == '~' then return '' elseif args[language] and args[language] ~= '' then return args[language] end end end

--[[ langSwitch This function is the core part of the LangSwitch template. Example Usage from a template:

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 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.isSupportedLanguage(lang) then lang = frame:callParserFunction("int", "lang") -- get user's chosen language end args.lang = nil return p._langSwitch(args, lang) end

--[[ autotranslate This function is the core part of the Autotranslate template. Usage from a template:

Parameters: frame.args.base - base page name frame.args.lang - desired language (often user's native language) Error Handling: ]] function p.autotranslate(frame)

-- switch to lowercase parameters to make them case independent local args = {} args = normalize_input_args(frame:getParent.args, args) args = normalize_input_args(frame.args, args)

-- get language fallback list if not args.lang or not mw.language.isSupportedLanguage(args.lang) then args.lang = frame:callParserFunction("int", "lang") -- get user's chosen language end local langList = mw.language.getFallbacksFor(args.lang) table.insert(langList, 1, args.lang)

-- find base page local base = args.base args.base = nil assert(base and #base > 0, 'Base page not provided for autotranslate') if not mw.ustring.find(base, ':') then -- if base page does not indicate namespace base = 'Template:' .. base -- than assume it is a template end

-- find base template language subpage local page = nil for _, language in ipairs(langList) do if mw.title.new(base .. '/' .. language).exists then page = base .. '/' .. language -- returns only the page break end end assert(page, string.format('No fallback page found for autotranslate (base=%s, lang=%s)', base, args.lang))

-- Transclude with template arguments the same as the ones passed to  template. return frame:expandTemplate{title = page, args = args} end

--[[ translatelua Allows easy translation or internalization of pages in Lua. Example Usage from a template:

Parameters: frame.args.1 - name of translation module frame.args.2 - field name of the structure in Module:[frame.args.1] to use frame.args.lang - desired language (often user's native language) Error Handling: ]] function p.translatelua(frame) local lang = frame.args.lang local page = require('Module:' .. mw.text.trim(frame.args[1])) -- page should only contain a simple of translations if not lang or mw.text.trim(lang) == '' then lang = frame:callParserFunction("int", "lang") end if frame.args[2] then page = page[mw.text.trim(frame.args[2])] end return p._langSwitch(page, lang) end

-- fblist Similar to mw.language.getFallbacksFor(lang) but uses Commons old fallback chain Parameters:  lang - desired language (often user's native language) Error Handling: function p.fblist(lang) -- list the full fallback chain from a language to en	local fbtable = p.fallbackloop{lang:lower} table.insert(fbtable, 'default') table.insert(fbtable, 'en') return fbtable end

local function _inArray(x, t)	for i, v in ipairs(t) do		if v == x then return i end end return -1 end

function p.fallbackloop(fbtable) --list of fallback languages in string format (more convenient than tables) local langlist = require('Module:Fallbacklist') local changes = false for i, j in ipairs(fbtable) do		local seq = langlist[j] if seq then for k, l in ipairs(seq) do				if _inArray(l, fbtable) == -1 then table.insert(fbtable, l)					changes = true end end end end if changes then return p.fallbackloop(fbtable) end return fbtable end

return p