require('Module:No globals');  local getArgs = require ('Module:Arguments').getArgs; local override_data = mw.loadData ('Module:Language/data/ISO 639 override'); --local override_data = mw.loadData ('Module:Language/data/ISO 639 override/sandbox'); local deprecated_data = mw.loadData ('Module:Language/data/ISO 639 deprecated'); local parts = {  {'Module:Language/data/ISO 639-1', '1'},  {'Module:Language/data/ISO 639-2', '2'},  {'Module:Language/data/ISO 639-2B', '2B'},  {'Module:Language/data/ISO 639-3', '3'},  {'Module:Language/data/ISO 639-5', '5'},  }   --[[--------------------------< E R R O R _ M E S S A G E S >--------------------------------------------------  ]]  local error_messages = {  ['err_msg'] = '<span style="font-size:100%;" class="error show_639_err_msgs">error: $1 ([[Template:ISO 639 name|help]])</span>',  ['err_text'] = { -- error messages used only in the code to name functions  ['ietf'] = '$1 is an IETF tag', -- $1 is the ietf tag  ['required'] = 'ISO 639$1 code is required', -- $1 is the 639 '-1', '-2', '-3', '-5' part suffix; may be empty string   -- code to name functions and iso_639_name_to_code()  ['not_found'] = '$1 not found in ISO 639-$2 list', -- $1 is code or language name; $2 is 639 part suffix(es)   -- iso_639_name_to_code() only  ['name'] = 'language name required',  ['not_part'] = '$1 not an ISO 639 part', -- $1 is invalid 639 suffix (without hyphen)   ['code_name'] = 'language code or name required', -- iso_639() only  }  }  local error_cat = '[[Category:ISO 639 name template errors]]';   --[[--------------------------< S U B S T I T U T E >----------------------------------------------------------  Populates numbered arguments in a message string using an argument table.  ]]  local function substitute (msg, args)  return args and mw.message.newRawMessage (msg, args):plain() or msg; end   --[[--------------------------< E R R O R _ M S G >------------------------------------------------------------  create an error message  ]]  local function error_msg (msg, arg, hide, nocat)  local retval = '';  if not hide then  retval = substitute (error_messages.err_msg, substitute (error_messages.err_text[msg], arg));  retval = nocat and retval or (retval .. error_cat);  end  return retval end   --[[--------------------------< I S _ S E T >------------------------------------------------------------------  Returns true if argument is set; false otherwise. Argument is 'set' when it exists (not nil) or when it is not an empty string.  ]]  local function is_set (var)  return not (var == nil or var == ''); end   --[=[-------------------------< M A K E _ W I K I L I N K >----------------------------------------------------  Makes a wikilink; when both link and display text is provided, returns a wikilink in the form [[L|D]]; if only link is provided, returns a wikilink in the form [[L]]; if neither are provided or link is omitted, returns an empty string.  ]=]  local function make_wikilink (link, display)  if is_set (link) then  if is_set (display) then  return table.concat ({'[[', link, '|', display, ']]'});  else  return table.concat ({'[[', link, ']]'});  end  else  return '';  end end   --[[--------------------------< L A N G _ N A M E _ G E T >----------------------------------------------------  returns first listed language name for code from data{} table; strips parenthetical disambiguation; wikilinks to the language article if link is true; returns nil else  ]]  local function lang_name_get (code, data, link, label, raw)  local name;  if data[code] then -- name = raw and data[code][1] or data[code][1]:gsub ('%s*%b()', ''); -- get the name; strip parenthetical disambiguators if any when <raw> is false  if raw then  name = data[code][1];  else  name = data[code][1]:gsub ('%s*%b()', ''); -- strip parenthetical disambiguators if any  name = name:gsub ('([^,]-), +(.+)', '%2 %1'); -- if inverted, uninvert  end  if link then -- make a link to the language article?  if name:find ('languages') or name:find ('[Ll]anguage$') then  name = make_wikilink (name, label); -- simple wikilink for collective languages or langauges ending in 'Language' unless there is a label  elseif override_data.article_name[code] then  name = make_wikilink (override_data.article_name[code][1], label or name); -- language name or label with wikilink from override data  else  name = make_wikilink (name .. ' language', label or name); -- [[name language|name]] or [[name language|label]]  end  end  return name;  end end   --[[--------------------------< A D D _ I E T F _ E R R O R _ M S G >------------------------------------------  assembles return-text (language code, language name, or error message) with IETF error message into properly formatted readable text  |hide-err=yes suppresses error message and category |cat=no supresses category  ]]  local function add_ietf_error_msg (text, ietf_err, hide, nocat)  if hide then  ietf_err = '';  end   if not nocat then -- |cat= empty or omitted -> nocat=false  nocat = '' == ietf_err; -- spoof; don't add cat when no error  end   return table.concat ({ -- tack on ietf error message if one exists  text, -- code name, language name, or error message  '' ~= ietf_err and ' ' or '', -- needs a space when ietf_err is not empty  ietf_err,  nocat and '' or error_cat, -- add error category when |cat=<aynthing but 'no'>  }); end   --[[--------------------------< G E T _ P A R T _ I N D E X >--------------------------------------------------  gets index suitable for parts{} table from ISO 639-<part> (usually args[2])  return valid index [1] - [5]; nil else  1 <- part ['1']  2 <- part ['2'] -- this is part 2T  3 <- part ['2B']  4 <- part ['3']  nil <- part ['4'] -- there is no part 4  5 <- part ['5']  ]]  local function get_part_index (part)  return ({['1']=1, ['2']=2, ['2B']=3, ['3']=4, ['4']=nil, ['5']=5})[part] end   --[[--------------------------< I S O _ 6 3 9 _ C O D E _ T O _ N A M E _ C O M M O N >------------------------  this is code that is common to all of the iso_639_code_n_to_name() functions which serve only as template entry points to provide the frame, the name of the appropriate data source, and to identify which 639 part applies.  this function returns a language name or an error message. data is searched in this order:  part-specific override data -> standard part data -> part-specific deprecated data  a second retval used by _iso_639_code_to_name() is true when a code is found; nil else  ]]  local function iso_639_code_to_name_common (args, source, part)  local hide = 'yes' == args['hide-err']; -- suppress error messages and error categorization  local nocat = 'no' == args.cat; -- suppress error categorization (primarily for demo use)  local raw = 'yes' == args.raw; -- disable override and dab removal  local data; -- one of the override or part tables  local name; -- holds language name from data   if not args[1] then -- if code not provided in the template call  return error_msg ('required', '-' .. part, hide, nocat); -- abandon  end   local code; -- used for error messaging  local ietf_err; -- holds an error message when args[1] (language code) is in IETF tag form (may or may not be a valid IETF tag)  code, ietf_err = args[1]:gsub('(.-)%-.*', '%1'); -- strip ietf subtags; ietf_err is non-zero when subtags are stripped  ietf_err = (0 ~= ietf_err) and error_msg ('ietf', args[1], hide, nocat) or ''; -- when tags are stripped create an error message; empty string for concatenation else   if not raw then -- when raw is true, fetch name as is from part data; ignore override  data = override_data['override_' .. part]; -- get override data for this part  name = lang_name_get (code:lower(), data, args.link, args.label, raw); -- get override language name if there is one  end   if not name then  data = mw.loadData (source); -- get the data for this ISO 639 part  name = lang_name_get (code:lower(), data, args.link, args.label, raw); -- get language name if there is one  end   if not name then -- TODO: do something special to indicate when a name is fetched from deprecated data?  data = deprecated_data['deprecated_' .. part]; -- get deprecated data for this part  name = lang_name_get (code:lower(), data, args.link, args.label, raw); -- get deprecated language name if there is one   if not name then  return error_msg ('not_found', {code, part}, hide, nocat); -- code not found, return error message  end  end  return add_ietf_error_msg (name, ietf_err, hide, nocat), true; -- return language name with ietf error message if any; true because we found a code end   --[[--------------------------< _ I S O _ 6 3 9 _ C O D E _ T O _ N A M E >------------------------------------  searches through the ISO 639 language tables for a name that matches the supplied code. on success returns first language name that matches code from template frame perhaps with an error message and a second return value of true; on failure returns an error message and a second return value of nil. The second return value is a return value used by iso_639_code_exists()  looks first in the override data and then sequentially in the 639-1, -2, -3, and -5 data  ]]  local function _iso_639_code_to_name (frame)  local args = getArgs(frame);  local hide = 'yes' == args['hide-err']; -- suppress error messages and error categorization  local nocat = 'no' == args.cat; -- suppress error categorization (primarily for demo use)   if not args[1] then -- if code not provided in the template call  return error_msg ('required', '', hide, nocat); -- abandon  end   local name; -- the retrieved language name and / or error message  local found; -- set to true when language name is found   for _, part in ipairs (parts) do  name, found = iso_639_code_to_name_common (args, part[1], part[2]);  if found then  return name, true; -- second retval for iso_639_name_exists()  end  end   return error_msg ('not_found', {args[1], '1, -2, -2B, -3, -5'}, hide, nocat); -- here when code (args[1]) is not found in the data tables end   --[[--------------------------< I S O _ 6 3 9 _ C O D E _ T O _ N A M E >--------------------------------------  template entry point; returns first language name that matches code from template frame or an error message looks first in the override data and then sequentially in the 639-1, -2, -3, and -5 data  ]]  local function iso_639_code_to_name (frame)  local ret_val = _iso_639_code_to_name (frame); -- ignore second return value  return ret_val; -- return language name and / or error message end   --[[--------------------------< I S O _ 6 3 9 _ C O D E _ E X I S T S >----------------------------------------  template entry point; returns true if language code maps to a language name; intended as a replacement for:  {{#exist:Template:ISO 639 name <code>|<exists>|<doesn't exist>}} Instead of that expensive parser function call use this function:  {{#if:{{#invoke:ISO 639 name|iso_639_code_exists|<code>}}|<exists>|<doesn't exist>}} on success, returns true; nil else  ]]  local function iso_639_code_exists (frame)  local _, exists;  _, exists = _iso_639_code_to_name (frame); -- ignore name/error message return; <exists> is true when name found for code; nil else  return exists; end   --[[--------------------------< I S O _ 6 3 9 _ C O D E _ 1 _ T O _ N A M E >----------------------------------  template entry point; returns first language name that matches ISO 639-1 code from template frame or an error message  ]]  local function iso_639_code_1_to_name (frame)  local args = getArgs (frame);  local retval = iso_639_code_to_name_common (args, parts[1][1], parts[1][2]); -- suppress second return value  return retval; end   --[[--------------------------< I S O _ 6 3 9 _ C O D E _ 2 _ T O _ N A M E >----------------------------------  template entry point; returns first language name that matches ISO 639-2 code from template frame or an error message  ]]  local function iso_639_code_2_to_name (frame)  local args = getArgs (frame);  local retval = iso_639_code_to_name_common (args, parts[2][1], parts[2][2]); -- suppress second return value  return retval; end   --[[--------------------------< I S O _ 6 3 9 _ C O D E _ 2 B _ T O _ N A M E >--------------------------------  template entry point; returns first language name that matches ISO 639-2 code from template frame or an error message  ]]  local function iso_639_code_2B_to_name (frame)  local args = getArgs (frame);  local retval = iso_639_code_to_name_common (args, parts[3][1], parts[3][2]); -- suppress second return value  return retval; end   --[[--------------------------< I S O _ 6 3 9 _ C O D E _ 3 _ T O _ N A M E >----------------------------------  template entry point; returns first language name that matches ISO 639-3 code from template frame or an error message  ]]  local function iso_639_code_3_to_name (frame)  local args = getArgs (frame);  local retval = iso_639_code_to_name_common (args, parts[4][1], parts[4][2]); -- suppress second return value  return retval; end   --[[--------------------------< I S O _ 6 3 9 _ C O D E _ 5 _ T O _ N A M E >----------------------------------  template entry point; returns first language name that matches ISO 639-5 code from template frame or an error message  ]]  local function iso_639_code_5_to_name (frame)  local args = getArgs (frame);  local retval = iso_639_code_to_name_common (args, parts[5][1], parts[5][2]); -- index [4] -> part 5 because there is no part 4; suppress second return value  return retval; end   --[[--------------------------< N A M E _ I N _ P A R T _ C O D E _ G E T >------------------------------------  indexes into the <name_data> using <name> and extracts the language code assigned to <part> (1, 2, 2B, 3, 5). attempts to index override data first; returns code on success, nil else  ]]  local function name_in_part_code_get (name, part, part_idx, name_data)  return name_data[name] and (  name_data[name][part_idx+5] or -- see if the name exists in the part's override table  name_data[name][part_idx] or -- see if the name exists in the part's main table  name_data[name][part_idx+10] -- see if the name exists in the part's deprecated table  ); end   --[[--------------------------< _ I S O _ 6 3 9 _ N A M E _ T O _ C O D E >------------------------------------  module entry point; returns ISO 639-1, -2, -2B, -3, or -5 code associated with language name according to part (1, 2, 2B, 3, 5) argument; when part is not provided scans 1, 2, 2B, 3, 5 and returns first code  override data are examined first  <args> is frame arguments from getArgs(frame)  ]]  local function _iso_639_name_to_code (args)  local hide = 'yes' == args['hide-err']; -- suppress error messages and error categorization  local nocat = 'no' == args.cat; -- suppress error categorization (primarily for demo use)   if not args[1] then  return error_msg ('name', '', hide, nocat); -- abandon when language name missing  end   local name = args[1]; -- used in error messaging  local lc_name = name:gsub(' +', ' '):lower(); -- lowercase version of name for indexing into the data table; strip extraneous space characters   local part_idx;  local part = args[2];  if part then  part_idx = get_part_index (part);  if not part_idx then  return error_msg ('not_part', part, hide, nocat); -- abandon; args[2] is not a valid ISO 639 part  end  end   local name_data = mw.loadData ('Module:Language/data/ISO 639 name to code'); -- ISO 639 language names to code table -- local name_data = mw.loadData ('Module:Language/data/ISO 639 name to code/sandbox'); -- ISO 639 language names to code table   local code;   if part then  code = name_in_part_code_get (lc_name, part, part_idx, name_data); -- search the specified override table + part table  else  for part_idx, part_tag in ipairs ({'1', '2', '2B', '3', '5'}) do -- no part provided, spin through all parts override first and get the first available code  code = name_in_part_code_get (lc_name, part_tag, part_idx, name_data);  if code then -- nil when specified <part> does not have code for specified language <name>  break; -- when code is not nil, done  end  end  end   if code then  return code, true;  end  return error_msg ('not_found', {name, part or '1, -2, -2B, -3, -5'}, hide, nocat), false; end   --[[--------------------------< I S O _ 6 3 9 _ N A M E _ T O _ C O D E >--------------------------------------  template entry point; returns ISO 639-1, -2, -2B, -3, or -5 code associated with language name according to part (1, 2, 2B, 3, 5) argument; when part is not provided scans 1, 2, 2B, 3, 5 and returns first code  override data are examined first  args[1] is language name args[2] is ISO 639 part  ]]  local function iso_639_name_to_code (frame)  local args = getArgs(frame);  local result, _ = _iso_639_name_to_code (args); -- suppress true/false return used by iso_639_name_exists()  return result; end   --[[--------------------------< I S O _ 6 3 9 _ N A M E _ E X I S T S >----------------------------------------  template entry point; returns ISO 639-1, -2, -3, or -5 code associated with language name according to part (1, 2, 3, 5) argument; when part is not provided scans 1, 2, 3 , 5 and returns first code  override data are examined first  args[1] is language name args[2] is ISO 639 part  ]]  local function iso_639_name_exists (frame)  local args = getArgs(frame);  local _, result = _iso_639_name_to_code (args); -- suppress code return used by iso_639_name_to_code()  return result and true or nil; end   --[[--------------------------< I S O _ 6 3 9 >----------------------------------------------------------------  template entry point. returns:  language name if args[1] is valid language code  language code if args[1] is valid language name  this function is constrained to the ISO 639 part specified in args[2] which must be 1, 2, 2B, 3, or 5. When not provided all parts are tested. The first match is found  ]]  local function iso_639 (frame)  local args = getArgs (frame);  local hide = 'yes' == args['hide-err']; -- suppress error messages and error categorization  local nocat = 'no' == args.cat; -- suppress error categorization (primarily for demo use)  local result;  local found; -- set to true when language name is found   if not args[1] then  return error_msg ('code_name', '', hide, nocat);  end   local part = args[2];  if part then -- if ISO 639 part supplied  local part_idx = get_part_index (part); -- map index from <part>; anything else nil   if not part_idx then  return error_msg ('not_part', part, hide, nocat); -- abandon; args[2] is not a valid ISO 639 part  end   result, found = iso_639_code_to_name_common (args, parts[part_idx][1], parts[part_idx][2]); -- attempt to find a code match  if found then  return result; -- found the code so return the language name  end   result = _iso_639_name_to_code (args); -- might be a language name; return code if it is; error message or empty string else  return result; -- this way to suppress second return   else  for _, part in ipairs (parts) do -- for each of the iso 639 parts  result, found = iso_639_code_to_name_common (args, part[1], part[2]); -- attempt to find a code match  if found then  return result; -- found the code so return the language name  end  end  end   result = _iso_639_name_to_code (args); -- might be a language name; return code if it is; error message or empty string else  return result; -- this way to suppress second return end   --[[--------------------------< E X P O R T E D F U N C T I O N S >------------------------------------------ ]]  return {  iso_639 = iso_639, -- returns code when given name; returns name when given code   iso_639_code_exists = iso_639_code_exists,  iso_639_name_exists = iso_639_name_exists,   iso_639_code_to_name = iso_639_code_to_name,  iso_639_code_1_to_name = iso_639_code_1_to_name,  iso_639_code_2_to_name = iso_639_code_2_to_name,  iso_639_code_2B_to_name = iso_639_code_2B_to_name,  iso_639_code_3_to_name = iso_639_code_3_to_name,  iso_639_code_5_to_name = iso_639_code_5_to_name,   iso_639_name_to_code = iso_639_name_to_code,  };