Module:Mw lang

require('Module:No globals'); local getArgs = require('Module:Arguments').getArgs

----< E R R _ M S G _ M A K E >--

local function err_msg_make (msg) return ' error: ' .. msg .. ' not recognized ' end

--[[--< _ I S _ C O D E >--

local or required entry point

return true if is a mediawiki recognized code; false else

- language code to validate; expected to be lowercase without leading/trailing whitespace  - language code for target language; expected to be valid; expected to be lowercase without leading/trailing whitespace

specifying  may be a pointless exercise because of cldr fallback. For example, mw.language.fetchLanguageName (crh, sq) -> Crimean Turkish because the Albanian language definitions do not have an Albanian-language version of the language name

]]

local function _is_code (code, target_lang_code) code = mw.language.fetchLanguageName (code, target_lang_code); return '' ~= code; end

--[[--< _ _ V A L I D A T E _ T A R G E T _ L A N G _ C O D E >

validates target_lang_code as a know language code; returns two values when target_lang_code is valid, first return value holds target_lang_code; second return value is nil when target_lang_code is invalid, first retrun value is nil; second return value has error message

if target_lang_code argument is nil, (missing or empty in the invoke) use local wiki's language code

]]

local function __validate_target_lang_code (target_lang_code) local msg; if target_lang_code then													-- not missing or empty if not _is_code (target_lang_code) then									-- validate target_lang_code msg = err_msg_make ('target language code: ' .. target_lang_code); target_lang_code = nil;												-- unset as invalid end end if not target_lang_code then												-- if nil because missing or empty or because invlaid and we set it nil target_lang_code = mw.getContentLanguage:getCode;					-- use local wiki's language code end

return target_lang_code, msg;												-- target_lang_code is valid or nil; msg is nil or has an error message end

--[[--< I S _ C O D E >

module entry point

args[1]: language code -> args[2]: optional target language code; same as in ; defaults to the local wiki language

return true if is a mediawiki recognized code; nil else

]]

local function is_code (frame) local args = getArgs (frame, {		valueFunc = function (key, value)			return (value and '' ~= value) and value:lower:gsub ('^%s*(.-)%s*$', '%1') or nil;		end		}); local code = args[1]; local target_lang_code = __validate_target_lang_code (args[2]);

return code and _is_code (code, target_lang_code) and true or nil; end

--[[--< N A M E _ F R O M _ C O D E >--

module entry point

args[1]: language code args[2]: optional target language code; same as in ; defaults to the local wiki language

return language-name if language-code is a mediawiki recognized code; error message string else

returned language name not guarenteed to be in target_lang_code (if specified), because mw language lists are incomplete

]]

local function name_from_code (frame) local args = getArgs (frame, {		valueFunc = function (key, value)			return (value and '' ~= value) and value:lower:gsub ('%s*(.-)%s*', '%1') or nil;		end		}); local code = args[1]; if not code then return err_msg_make ('code: (empty)'); end local target_lang_code, msg = __validate_target_lang_code (args[2]); if msg then return msg; end

local name = mw.language.fetchLanguageName (code, target_lang_code);		-- returns empty string if code not found return '' ~= name and name or err_msg_make ('language code: ' .. code);		-- return language name or error message end

--[[--< C O D E _ F R O M _ N A M E >--

local entry point

args[1]: language name args[2]: optional target language code; instruct this function to fetch language name list in 'this' language

return language-code if language-name is a mediawiki recognized name and target language code is valid; error message string else

second return value is a boolean used by is_name; true when name is found; false else

]]

local function _code_from_name (args) local name = args[1]; if not name then return err_msg_make ('name: (empty)'); end

local target_lang_code, msg = __validate_target_lang_code (args[2]);

if msg then return msg; end

local code_name_list = mw.language.fetchLanguageNames (target_lang_code, 'all');	-- get language code / name list in target_lang_code language indexed by language code local name_code_list = {};													-- to hold language name / code list indexed by name

for k, v in pairs (code_name_list) do										-- spin through the code / name list and name_code_list[v:lower] = k;											-- make a name / code list end

if name_code_list[name] then return name_code_list[name], true;										-- returns code when name is found and true for is_name else return err_msg_make ('language name: ' .. name), false;					-- return error message when name not found and false for is_name end end

--[[--< C O D E _ F R O M _ N A M E >--

module entry point

args[1]: language name args[2]: optional target language code; instruct this function to fetch language name list in 'this' language

return language-code if language-name is a mediawiki recognized name and target language code is valid; error message string else

]]

local function code_from_name (frame) local args = getArgs (frame, {		valueFunc = function (key, value)			return (value and '' ~= value) and value:lower:gsub ('^%s*(.-)%s*$', '%1') or nil;		end		}); local result, _ = _code_from_name (args);									-- suppress true/false return used by is_name return result; end

--[[--< I S _ N A M E >

return true if is a mediawiki recognized language name; false else

args[1]: language name args[2]: optional target language code; instructs _code_from_name to fetch language name list in 'this' language defaults to local wiki's language; when this parameter not valid, language name is assumed to be not valid

]]

local function is_name (frame) local args = getArgs (frame, {		valueFunc = function (key, value)			return (value and '' ~= value) and value:lower:gsub ('%s*(.-)%s*', '%1') or nil;		end		}); local _, result = _code_from_name (args);									-- suppress code return used by code_from_name return result and true or nil; end

----< E X P O R T E D  F U N C T I O N S >--

return { code_from_name = code_from_name, is_code = is_code, is_name = is_name, name_from_code = name_from_code,

_is_code = _is_code,														-- entry point from another module }