Module:Lang

 --[=[

 Lua support for the {{lang}}, {{langx}}, {{lang-??}}, and {{transliteration}} templates and replacement of various supporting templates. 

 ]=]

 require('strict');

 localgetArgs=require('Module:Arguments').getArgs;
 localunicode=require("Module:Unicode data");-- for is_Latin() and is_rtl()
 localyesno=require('Module:Yesno');

 localsandbox=(mw.getCurrentFrame():getTitle():match('/sandbox')or'');-- when called from a sandbox template or module load sandbox data and sandbox configuration

 locallang_data=mw.loadData('Module:Lang/data'..sandbox);-- language name override and transliteration tool-tip tables
 locallang_name_table=lang_data.lang_name_table;-- language codes, names, regions, scripts, suppressed scripts
 locallang_table=lang_data.lang_name_table.lang;
 locallang_dep_table=lang_data.lang_name_table.lang_dep;
 localscript_table=lang_data.lang_name_table.script;
 localregion_table=lang_data.lang_name_table.region;
 localvariant_table=lang_data.lang_name_table.variant;
 localsuppressed_table=lang_data.lang_name_table.suppressed;
 localoverride_table=lang_data.override;

 localsynonym_table=mw.loadData('Module:Lang/ISO 639 synonyms');-- ISO 639-2/639-2T code translation to 639-1 code

 localcfg=mw.loadData('Module:Lang/configuration'..sandbox);-- for internationalization

 localis_latn_data=mw.loadData('Module:Lang/data/is latn data');
 localsizeof_ranges_t=is_latn_data.sizeof_ranges_t;

 localnamespace=mw.title.getCurrentTitle().namespace;-- used for categorization

 localcontent_lang=mw.language.getContentLanguage();
 localthis_wiki_lang_tag=content_lang.code;-- get this wiki's language tag
 localthis_wiki_lang_dir=content_lang:getDir();-- get this wiki's language direction

 localinitial_style_state;-- set by lang_xx_normal() and lang_xx_italic()

 localmaint_cats={};-- maintenance categories go here
 localmaint_msgs={};-- and their messages go here


 --[[--------------------------< M A K E _ E R R O R _ S P A N >--------------------------------------------------

 ]]

 localfunctionmake_error_span(template,msg)
 returntable.concat({'<span style="color:#d33">',cfg.misc_text_t.error,': ',template,msg,'</span>'})
 end


 --[[--------------------------< S U B S T I T U T E >----------------------------------------------------------

 Substitutes 1,ドル 2,ドル etc in <message> with data from <data_t>. Returns plain-text substituted string when
 <data_t> not nil; returns <message> else.

 ]]

 localfunctionsubstitute(message,data_t)
 returndata_tandmw.message.newRawMessage(message,data_t):plain()ormessage;
 end


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

 Assembles an error message from template name, message text, help link, and error category.

 ]]

 localfunctionmake_error_msg(msg,args_t,template)
 localcategory;
 localtext;-- handle the oddity that is {{langx}}
 ifcfg.templates_t.langxx==templatethen
 text=args_t.textorargs_t[1];-- for {{lang-xx}}
 else
 text=args_t.textorargs_t[2];-- for {{lang}}, {{langx}}, and {{transliteration}}
 end

 ifcfg.templates_t.transliteration==templatethen
 category=cfg.make_error_msg_t.xlit_err_cat;
 else
 category=cfg.make_error_msg_t.lang_err_cat;
 end

 localcategory_link=((0==namespaceor10==namespace)andnotargs_t.nocat)andsubstitute('[[Category:1ドル]]',{category})or'';
 returnsubstitute('[1ドル] <span style="color:#d33">2ドル: &#x7B;{3ドル}}: 4ドル ([[:Category:5ドル|6ドル]])</span>7ドル',-- &#x7B; prevents template name from being treated as a template call in certain situations
 {
 textorcfg.make_error_msg_t.undefined,
 cfg.misc_text_t.error,
 template,
 msg,
 category,
 cfg.misc_text_t.help,
 category_link
 })
 end


 --[[--------------------------< P A R A M E T E R _ V A L I D A T E >------------------------------------------

 ]]

 localfunctionparameter_validate(args_t,template)
 localerr_msg=cfg.parameter_validate_t.invalid_param;

 ifcfg.templates_t.lang==templatethen-- for {{lang}}
 forparam,_inpairs(args_t)do
 ifnotcfg.known_params_t.params_lang_t[param]and-- unique {{lang}} parameters
 notcfg.known_params_t.common_params_all_t[param]then-- common to all
 returnsubstitute(err_msg,{param});-- <param> not found so abandon
 end
 end
 elseifcfg.templates_t.langx==templatethen-- for {{langx}}
 forparam,_inpairs(args_t)do
 ifnotcfg.known_params_t.params_langx_t[param]and-- unique {{langx}} parameters
 notcfg.known_params_t.params_x_t[param]and-- common to {{langx}} and {{lang-xx}}
 notcfg.known_params_t.common_params_all_t[param]then-- common to all
 returnsubstitute(err_msg,{param});-- <param> not found so abandon
 end
 end
 elseifcfg.templates_t.langxx==templatethen-- for {{lang-xx}}
 forparam,_inpairs(args_t)do
 ifnotcfg.known_params_t.params_lang_xx_t[param]and-- unique {{lang-xx}} parameters
 notcfg.known_params_t.params_x_t[param]and-- common to {{langx}} and {{lang-xx}}
 notcfg.known_params_t.common_params_all_t[param]then-- common to all
 returnsubstitute(err_msg,{param});-- <param> not found so abandon
 end
 end
 end
 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.

 ]]

 localfunctionis_set(var)
 returnnot(var==nilorvar=='');
 end


 --[[--------------------------< I N V E R T _ I T A L I C S >-------------------------------------------------

 This function attempts to invert the italic markup a args.text by adding/removing leading/trailing italic markup
 in args.text. Like |italic=unset, |italic=invert disables automatic italic markup. Individual leading/trailing
 apostrophes are converted to their HTML numeric entity equivalent so that the new italic markup doesn't become
 bold markup inadvertently.

 Leading and trailing wiki markup is extracted from args.text into separate table elements. Addition, removal,
 replacement of wiki markup is handled by a string.gsub() replacement table operating only on these separate elements.
 In the string.gsub() matching pattern, '.*' matches empty string as well as the three expected wiki markup patterns.

 This function expects that markup in args.text is complete and correct; if it is not, oddness may result.

 ]]

 localfunctioninvert_italics(source)
 localinvert_pattern_table={-- leading/trailing markup add/remove/replace patterns
 [""]="\'\'",-- empty string becomes italic markup
 ["\'\'"]="",-- italic markup becomes empty string
 ["\'\'\'"]="\'\'\'\'\'",-- bold becomes bold italic
 ["\'\'\'\'\'"]="\'\'\'",-- bold italic become bold
 };
 localseg={};

 source=source:gsub("%f[\']\'%f[^\']",'&#39;');-- protect single quote marks from being interpreted as bold markup

 seg[1]=source:match('^(\'\'+%f[^\']).+')or'';-- get leading markup, if any; ignore single quote
 seg[3]=source:match('.+(%f[\']\'\'+)$')or'';-- get trailing markup, if any; ignore single quote

 if''~=seg[1]and''~=seg[3]then-- extract the 'text' 
 seg[2]=source:match('^\'\'+%f[^\'](.+)%f[\']\'\'+$')-- from between leading and trailing markup
 elseif''~=seg[1]then
 seg[2]=source:match('^\'\'+%f[^\'](.+)')-- following leading markup
 elseif''~=seg[3]then
 seg[2]=source:match('(.+)%f[\']\'\'+$')-- preceding trailing markup
 else
 seg[2]=source-- when there is no markup
 end

 seg[1]=invert_pattern_table[seg[1]]orseg[1];-- replace leading markup according to pattern table
 seg[3]=invert_pattern_table[seg[3]]orseg[3];-- replace leading markup according to pattern table

 returntable.concat(seg);-- put it all back together and done
 end


 --[[--------------------------< V A L I D A T E _ I T A L I C >------------------------------------------------

 Validates |italic= or |italics= assigned values.

 When |italic= is set and has an acceptable assigned value, return the matching CSS font-style property value or,
 for the special case 'default', return nil.

 When |italic= is not set, or has an unacceptable assigned value, return nil and a nil error message.

 When both |italic= and |italics= are set, returns nil and a 'conflicting' error message.

 The return value nil causes the calling lang, lang_xx, or xlit function to set args.italic according to the template's
 defined default ('inherit' for {{lang}}, 'inherit' or 'italic' for {{lang-??}} depending on
 the individual template's requirements, 'italic' for {{transliteration}}) or to the value appropriate to |script=, if set ({{lang}}
 and {{lang-??}} only).

 Accepted values and the values that this function returns are are:
 	nil		-	when |italic= absent or not set; returns nil
 	default	-	for completeness, should rarely if ever be used; returns nil
 	yes		-	force args.text to be rendered in italic font; returns 'italic'
 	no		-	force args.text to be rendered in normal font; returns 'normal'
 	unset	-	disables font control so that font-style applied to text is dictated by markup inside or outside the template; returns 'inherit'
 	invert	-	disables font control so that font-style applied to text is dictated by markup outside or inverted inside the template; returns 'invert'

 ]]

 localfunctionvalidate_italic(args)
 localproperties={[cfg.keywords_t.affirmative]='italic',[cfg.keywords_t.negative]='normal',[cfg.keywords_t.unset]='inherit',[cfg.keywords_t.invert]='invert',[cfg.keywords_t.default]=nil};

 localcount=0
 for_,arginpairs{'italic','italics','i'}do
 ifargs[arg]then
 count=count+1
 end
 end

 ifcount>1then-- return nil and an error message if more than one is set 
 returnnil,cfg.validate_italic_t.multi_italic;
 end

 returnproperties[args.italicorargs.italicsorargs.i],nil;-- return an appropriate value and a nil error message
 end


 --[=[--------------------------< V A L I D A T E _ C A T _ A R G S >----------------------------------------------------------

 Default behavior of the {{lang}} and {{lang-??}} templates is to add categorization when the templates are used in main space.
 This default functionality may be suppressed by setting |nocat=yes or |cat=no. This function selects one of these two parameters
 to control categorization.

 Because having two parameters with 'opposite' names and 'opposite' values is confusing, this function accepts only affirmative
 values for |nocat= and only negative values for |cat=; in both cases the 'other' sense (and non-sense) is not accepted and the
 parameter is treated as if it were not set in the template.

 Sets args.nocat to true if categorization is to be turned off; to nil if the default behavior should apply.

 Accepted values for |nocat= are the text strings:
 	'yes', 'y', 'true', 't', on, '1'		-- [[Module:Yesno]] returns logical true for all of these; false or nil else
 for |cat=
 	'no', 'n', 'false', 'f', 'off', '0'		-- [[Module:Yesno]] returns logical false for all of these; true or nil else

 ]=]

 localfunctionvalidate_cat_args(args)
 ifnot(args.nocatorargs.cat)then-- both are nil, so categorize
 return;
 end

 iffalse==yesno(args.cat)ortrue==yesno(args.nocat)then
 args.nocat=true;-- set to true when args.nocat is affirmative; nil else (as if the parameter were not set in the template)
 else-- args.nocat is the parameter actually used.
 args.nocat=nil;
 end
 end


 --[[--------------------------< I N _ A R R A Y >--------------------------------------------------------------

 Whether needle is in haystack.

 ]]

 localfunctionin_array(needle,haystack)
 ifneedle==nilthen
 returnfalse;
 end
 forn,vinipairs(haystack)do
 ifv==needlethen
 returnn;
 end
 end
 returnfalse;
 end


 --[[--------------------------< F O R M A T _ I E T F _ T A G >------------------------------------------------

 Prettify IETF tags to use recommended subtag formats:
 	code: lower case
 	script: sentence case
 	region: upper case
 	variant: lower case
 	private: lower case prefixed with -x-

 ]]

 localfunctionformat_ietf_tag(code,script,region,variant,private)
 localout={};

 ifis_set(private)then
 returntable.concat({code:lower(),'x',private:lower()},'-');-- if private, all other tags ignored
 end

 table.insert(out,code:lower());
 ifis_set(script)then
 script=script:lower():gsub('^%a',string.upper);
 table.insert(out,script);
 end

 ifis_set(region)then
 table.insert(out,region:upper());
 end

 ifis_set(variant)then
 table.insert(out,variant:lower());
 end

 returntable.concat(out,'-');
 end


 --[[--------------------------< G E T _ I E T F _ P A R T S >--------------------------------------------------

 Extracts and returns IETF language tag parts:
 	primary language subtag (required) - 2 or 3 character IANA language code
 	script subtag - four character IANA script code
 	region subtag - two-letter or three digit IANA region code
 	variant subtag - four digit or 5-8 alnum variant code; only one variant subtag supported
 	private subtag - x- followed by 1-8 alnum private code; only supported with the primary language tag

 in any one of these forms
 	lang					lang-variant
 	lang-script				lang-script-variant
 	lang-region				lang-region-variant
 	lang-script-region		lang-script-region-variant
 	lang-x-private	

 each of lang, script, region, variant, and private, when used, must be valid.

 Languages with both two- and three-character code synonyms are promoted to the two-character synonym because
 the IANA registry file omits the synonymous three-character code; we cannot depend on browsers understanding
 the synonymous three-character codes in the lang= attribute.

 For {{lang-??}} templates, the parameters |script=, |region=, and |variant= are supported (not supported in {{lang}}
 because those parameters are superfluous to the IETF subtags in |code=).

 Returns six values; all lower case. Valid parts are returned as themselves; omitted parts are returned as empty strings, invalid
 parts are returned as nil; the sixth returned item is an error message (if an error detected) or nil.

 See http://www.rfc-editor.org/rfc/bcp/bcp47.txt section 2.1.

 ]]

 localfunctionget_ietf_parts(source,args_script,args_region,args_variant)
 localcode,script,region,variant,private;-- IETF tag parts

 ifnotis_set(source)then
 returnnil,nil,nil,nil,nil,cfg.get_ietf_parts_t.missing_lang_tag;
 end

 localpattern={-- table of tables holding acceptable IETF tag patterns and short names of the IETF part captured by the pattern
 {'^(%a%a%a?)%-(%a%a%a%a)%-(%a%a)%-(%d%d%d%d)$','s','r','v'},-- 1 - ll-Ssss-RR-variant (where variant is 4 digits)
 {'^(%a%a%a?)%-(%a%a%a%a)%-(%d%d%d)%-(%d%d%d%d)$','s','r','v'},-- 2 - ll-Ssss-DDD-variant (where region is 3 digits; variant is 4 digits)
 {'^(%a%a%a?)%-(%a%a%a%a)%-(%a%a)%-(%w%w%w%w%w%w?%w?%w?)$','s','r','v'},-- 3 - ll-Ssss-RR-variant (where variant is 5-8 alnum characters)
 {'^(%a%a%a?)%-(%a%a%a%a)%-(%d%d%d)%-(%w%w%w%w%w%w?%w?%w?)$','s','r','v'},-- 4 - ll-Ssss-DDD-variant (where region is 3 digits; variant is 5-8 alnum characters)

 {'^(%a%a%a?)%-(%a%a%a%a)%-(%d%d%d%d)$','s','v'},-- 5 - ll-Ssss-variant (where variant is 4 digits)
 {'^(%a%a%a?)%-(%a%a%a%a)%-(%w%w%w%w%w%w?%w?%w?)$','s','v'},-- 6 - ll-Ssss-variant (where variant is 5-8 alnum characters)

 {'^(%a%a%a?)%-(%a%a)%-(%d%d%d%d)$','r','v'},-- 7 - ll-RR-variant (where variant is 4 digits)
 {'^(%a%a%a?)%-(%d%d%d)%-(%d%d%d%d)$','r','v'},-- 8 - ll-DDD-variant (where region is 3 digits; variant is 4 digits)
 {'^(%a%a%a?)%-(%a%a)%-(%w%w%w%w%w%w?%w?%w?)$','r','v'},-- 9 - ll-RR-variant (where variant is 5-8 alnum characters)
 {'^(%a%a%a?)%-(%d%d%d)%-(%w%w%w%w%w%w?%w?%w?)$','r','v'},-- 10 - ll-DDD-variant (where region is 3 digits; variant is 5-8 alnum characters)

 {'^(%a%a%a?)%-(%d%d%d%d)$','v'},-- 11 - ll-variant (where variant is 4 digits)
 {'^(%a%a%a?)%-(%w%w%w%w%w%w?%w?%w?)$','v'},-- 12 - ll-variant (where variant is 5-8 alnum characters)

 {'^(%a%a%a?)%-(%a%a%a%a)%-(%a%a)$','s','r'},-- 13 - ll-Ssss-RR
 {'^(%a%a%a?)%-(%a%a%a%a)%-(%d%d%d)$','s','r'},-- 14 - ll-Ssss-DDD (region is 3 digits)

 {'^(%a%a%a?)%-(%a%a%a%a)$','s'},-- 15 - ll-Ssss

 {'^(%a%a%a?)%-(%a%a)$','r'},-- 16 - ll-RR
 {'^(%a%a%a?)%-(%d%d%d)$','r'},-- 17 - ll-DDD (region is 3 digits)

 {'^(%a%a%a?)$'},-- 18 - ll

 {'^(%a%a%a?)%-x%-(%w%w?%w?%w?%w?%w?%w?%w?)$','p'},-- 19 - ll-x-pppppppp (private is 1-8 alnum characters)
 }

 localt={};-- table of captures; serves as a translator between captured IETF tag parts and named variables

 fori,vinipairs(pattern)do-- spin through the pattern table looking for a match
 localc1,c2,c3,c4;-- captures in the 'pattern' from the pattern table go here

 c1,c2,c3,c4=source:match(pattern[i][1]);-- one or more captures set if source matches pattern[i])
 ifc1then-- c1 always set on match
 code=c1;-- first capture is always code
 t={
 [pattern[i][2]or'x']=c2,-- fill the table of captures with the rest of the captures
 [pattern[i][3]or'x']=c3,-- take index names from pattern table and assign sequential captures
 [pattern[i][4]or'x']=c4,-- index name may be nil in pattern[i] table so "or 'x'" spoofs a name for this index in this table
 };
 script=t.sor'';-- translate table contents to named variables;
 region=t.ror'';-- absent table entries are nil so set named IETF parts to empty string for concatenation
 variant=t.vor'';
 private=t.por'';
 break;-- and done
 end
 end

 ifnotcodethen
 returnnil,nil,nil,nil,nil,substitute(cfg.get_ietf_parts_t.unrecog_tag,{source});-- don't know what we got but it is malformed
 end

 code=code:lower();-- ensure that we use and return lower case version of this

 ifnot(override_table[code]orlang_table[code]orsynonym_table[code]orlang_dep_table[code])then
 returnnil,nil,nil,nil,nil,substitute(cfg.get_ietf_parts_t.unrecog_code,{code});-- invalid language code, don't know about the others (don't care?)
 end

 ifsynonym_table[code]then-- if 639-2/639-2T code has a 639-1 synonym
 table.insert(maint_cats,substitute(cfg.get_ietf_parts_t.maint_promo_cat,{code}));
 table.insert(maint_msgs,substitute(cfg.get_ietf_parts_t.maint_promo_msg,{code,synonym_table[code]}));
 code=synonym_table[code];-- use the synonym
 end

 ifis_set(script)then
 ifis_set(args_script)then
 returncode,nil,nil,nil,nil,cfg.get_ietf_parts_t.redundant_scr;-- both code with script and |script= not allowed
 end
 else
 script=args_scriptor'';-- use args.script if provided
 end

 ifis_set(script)then
 script=script:lower();-- ensure that we use and return lower case version of this
 ifnotscript_table[script]then
 returncode,nil,nil,nil,nil,substitute(cfg.get_ietf_parts_t.unrecog_scr_code,{script,code});-- language code OK, invalid script, don't know about the others (don't care?)
 end
 end
 ifsuppressed_table[script]then-- ensure that code-script does not use a suppressed script
 ifin_array(code,suppressed_table[script])then
 returncode,nil,nil,nil,nil,substitute(cfg.get_ietf_parts_t.script_code,{script,code});-- language code OK, script is suppressed for this code
 end
 end

 ifis_set(region)then
 ifis_set(args_region)then
 returncode,nil,nil,nil,nil,cfg.get_ietf_parts_t.redundant_reg;-- both code with region and |region= not allowed
 end
 else
 region=args_regionor'';-- use args.region if provided
 end

 ifis_set(region)then
 region=region:lower();-- ensure that we use and return lower case version of this
 ifnotregion_table[region]then
 returncode,script,nil,nil,nil,substitute(cfg.get_ietf_parts_t.unrecog_reg_code,{region,code});
 end
 end

 ifis_set(variant)then
 ifis_set(args_variant)then
 returncode,nil,nil,nil,nil,cfg.get_ietf_parts_t.redundant_var;-- both code with variant and |variant= not allowed
 end
 else
 variant=args_variantor'';-- use args.variant if provided
 end

 ifis_set(variant)then
 variant=variant:lower();-- ensure that we use and return lower case version of this
 ifnotvariant_table[variant]then-- make sure variant is valid
 returncode,script,region,nil,nil,substitute(cfg.get_ietf_parts_t.unrecog_var,{variant});
 end-- does this duplicate/replace tests in lang() and lang_xx()?
 ifis_set(script)then-- if script set it must be part of the 'prefix'
 ifnotin_array(table.concat({code,'-',script}),variant_table[variant]['prefixes'])then
 returncode,script,region,nil,nil,substitute(cfg.get_ietf_parts_t.unrecog_var_code_scr,{variant,code,script});
 end
 elseifis_set(region)then-- if region set, there are some prefixes that require lang code and region (en-CA-newfound)
 ifnotin_array(code,variant_table[variant]['prefixes'])then-- first see if lang code is all that's required (en-oxendict though en-GB-oxendict is preferred)
 ifnotin_array(table.concat({code,'-',region}),variant_table[variant]['prefixes'])then-- now try for lang code and region (en-CA-newfound)
 returncode,script,region,nil,nil,substitute(cfg.get_ietf_parts_t.unrecog_var_code_reg,{variant,code,region});
 end
 end
 else-- cheap way to determine if there are prefixes; fonipa and others don't have prefixes; # operator always returns 0
 ifvariant_table[variant]['prefixes'][1]andnotin_array(code,variant_table[variant]['prefixes'])then
 returncode,script,region,nil,nil,substitute(cfg.get_ietf_parts_t.unrecog_var_code,{variant,code});
 end
 end
 end

 ifis_set(private)then
 private=private:lower();-- ensure that we use and return lower case version of this
 ifnotoverride_table[table.concat({code,'-x-',private})]then-- make sure private tag is valid; note that index 
 returncode,script,region,nil,nil,substitute(cfg.get_ietf_parts_t.unrecog_pri,{private});
 end
 end
 returncode,script,region,variant,private,nil;-- return the good bits; make sure that msg is nil
 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.

 ]=]

 localfunctionmake_wikilink(link,display)
 ifis_set(link)then
 ifis_set(display)then
 returntable.concat({'[[',link,'|',display,']]'});
 else
 returntable.concat({'[[',link,']]'});
 end
 else
 return'';
 end
 end


 --[[--------------------------< D I V _ M A R K U P _ A D D >--------------------------------------------------

 Adds <i> and </i> tags to list-item text or to implied <p>..</p> text. Mixed not supported.

 ]]

 localfunctiondiv_markup_add(text,style)
 iftext:find('^\n[%*:;#]')then-- look for list markup; list markup must begin at start of text
 if'italic'==stylethen
 returntext:gsub('(\n[%*:;#]+)([^\n]+)','%1<i>%2</i>');-- insert italic markup at each list item
 else
 returntext;
 end
 end

 iftext:find('\n+')then-- look for any number of \n characters in text
 text=text:gsub('([^\n])\n([^\n])','%1 %2');-- replace single newline characters with a space character which mimics MediaWiki

 if'italic'==stylethen
 text=text:gsub('[^\n]+','<p><i>%1</i></p>');-- insert p and italic markup tags at each implied p (two or more consecutive '\n\n' sequences)
 else
 text=text:gsub('[^\n]+','<p>%1</p>');-- insert p markup at each implied p
 text=text:gsub('\n','');-- strip newline characters
 end
 end

 returntext;
 end


 --[[--------------------------< T I T L E _ W R A P P E R _ M A K E >------------------------------------------

 Makes a <span title="<title text>"><content_text></span> or <div title="<title text>"><content_text></div> where
 <title text> is in the tool-tip in the wiki's local language and <content_text> is non-local-language text in
 HTML markup. This because the lang= attribute applies to the content of its enclosing tag.

 <tag> holds a string 'div' or 'span' used to choose the correct wrapping tag.

 ]]

 localfunctiontitle_wrapper_make(title_text,content_text,tag)
 localwrapper_t={};

 table.insert(wrapper_t,table.concat({'<',tag}));-- open opening wrapper tag
 table.insert(wrapper_t,' title=\"');-- begin title attribute
 table.insert(wrapper_t,title_text);-- add <title_text>
 table.insert(wrapper_t,'\">');-- end title attribute and close opening wrapper tag
 table.insert(wrapper_t,content_text);-- add <content_text>
 table.insert(wrapper_t,table.concat({'</',tag,'>'}));-- add closing wrapper tag

 returntable.concat(wrapper_t);-- make a big string and done
 end


 --[[--------------------------< M A K E _ T E X T _ H T M L >--------------------------------------------------

 Add the HTML markup to text according to the type of content that it is: <span> or <i> tags for inline content or
 <div> tags for block content

 The lang= attribute also applies to the content of the tag where it is placed so this is wrong because 'Spanish
 language text' is English:
 	<i lang="es" title="Spanish language text">casa</i>
 should be:
 	<span title="Spanish language text"><i lang="es">casa</i></span>
 or for <div>...</div>:
 	<div title="Spanish language text"><div lang="es"><spanish-language-text></div></div>

 ]]

 localfunctionmake_text_html(code,text,tag,rtl,style,size,language)
 localhtml_t={};
 localstyle_added='';
 localwrapper_tag=tag;-- <tag> gets modified so save a copy for use when/if we create a wrapper span or div

 iftext:match('^%*')then
 table.insert(html_t,'&#42;');-- move proto language text prefix outside of italic markup if any; use numeric entity because plain splat confuses MediaWiki
 text=text:gsub('^%*','');-- remove the splat from the text
 end

 if'span'==tagthen-- default HTML tag for inline content
 if'italic'==stylethen-- but if italic
 tag='i';-- change to <i> tags
 end
 else-- must be div so go
 text=div_markup_add(text,style);-- handle implied <p>, implied <p> with <i>, and list markup (*;:#) with <i>
 end

 table.insert(html_t,table.concat({'<',tag}));-- open the <i>, <span>, or <div> HTML tag
 code=code:gsub('%-x%-.*','');-- strip private use subtag from code tag because meaningless outside of Wikipedia
 table.insert(html_t,table.concat({' lang="',code,'\"'}));-- add language attribute

 if(rtlorunicode.is_rtl(text))and('ltr'==this_wiki_lang_dir)then-- text is right-to-left on a left-to-right wiki
 table.insert(html_t,' dir="rtl"');-- add direction attribute for right-to-left languages
 elseifnot(rtlorunicode.is_rtl(text))and('rtl'==this_wiki_lang_dir)then-- text is left-to-right on a right-to-left wiki
 table.insert(html_t,' dir="ltr"');-- add direction attribute for left-to-right languages
 end

 if'normal'==stylethen-- when |italic=no
 table.insert(html_t,' style=\"font-style: normal;');-- override external markup, if any
 style_added='\"';-- remember that style attribute added and is not yet closed
 end

 ifis_set(size)then-- when |size=<something>
 ifis_set(style_added)then
 table.insert(html_t,table.concat({' font-size: ',size,';'}));-- add when style attribute already inserted
 else
 table.insert(html_t,table.concat({' style=\"font-size: ',size,';'}));-- create style attribute
 style_added='\"';-- remember that style attribute added and is not yet closed
 end
 end

 table.insert(html_t,table.concat({style_added,'>'}));-- close the opening HTML tag
 table.insert(html_t,text);-- insert the text

 table.insert(html_t,table.concat({'</',tag,'>'}));-- close the 'text' <i>, <span>, or <div> HTML tag

 ifis_set(language)then-- create a <title_text> string for the title= attribute in a wrapper span or div
 localtitle_text;
 if'zxx'==codethen-- special case for this tag 'no linguistic content'
 title_text=substitute('1ドル 2ドル',{language,cfg.make_text_html_t.zxx});-- not a language so don't use 'language' in title text
 elseifmw.ustring.find(language,'languages',1,true)then
 title_text=substitute('1ドル 2ドル',{language,cfg.make_text_html_t.collective});-- for collective languages
 else
 title_text=substitute('1ドル-2ドル',{language,cfg.make_text_html_t.individual});-- for individual languages
 end

 returntitle_wrapper_make(title_text,table.concat(html_t),wrapper_tag);
 else
 returntable.concat(html_t);
 end
 end


 --[=[-------------------------< M A K E _ C A T E G O R Y >----------------------------------------------------

 For individual language, <language>, returns:
 	[[Category:Articles containing <language>-language text]]

 For English:
 	[[Category:Articles containing explicitly cited English-language text]]

 For ISO 639-2 collective languages (and for 639-1 bh):
 	[[Category:Articles with text in <language> languages]]

 ]=]

 localfunctionmake_category(code,language_name,nocat,name_get)
 if((0~=namespace)ornocat)andnotname_getthen-- only categorize in article space
 return'';-- return empty string for concatenation
 end

 ifmw.ustring.find(language_name,'languages',1,true)then
 returnsubstitute('[[1ドル 2ドル]]',{cfg.make_category_t.collective_cat,language_name});
 end

 ifthis_wiki_lang_tag==codethen
 returnsubstitute('[[1ドル 2ドル 3ドル-4ドル]]',{-- unique category name for the local language
 cfg.make_category_t.cat_prefix,
 cfg.make_category_t.explicit_cat,
 language_name,
 cfg.make_category_t.cat_postfix,
 });
 else
 returnsubstitute('[[1ドル 2ドル-3ドル]]',{-- category for individual languages
 cfg.make_category_t.cat_prefix,
 language_name,
 cfg.make_category_t.cat_postfix,
 });
 end
 end


 --[[--------------------------< M A K E _ T R A N S L I T >----------------------------------------------------

 Return translit <i lang=xx-Latn>...</i> where xx is the language code; else return empty string.

 The value |script= is not used in {{transliteration}} for this purpose; instead it uses |code. Because language scripts
 are listed in the {{transliteration}} switches they are included in the data tables. The script parameter is introduced
 at {{Language with name and transliteration}}. If |script= is set, this function uses it in preference to code.

 To avoid confusion, in this module and the templates that use it, the transliteration script parameter is renamed
 to be |translit-script= (in this function, tscript).

 This function is used by both lang_xx() and xlit()
 	lang_xx() always provides code, language_name, and translit; may provide tscript; never provides style
 	xlit() always provides language_name, translit, and one of code or tscript, never both; always provides style

 For {{transliteration}}, style only applies when a language code is provided.

 ]]

 localfunctionmake_translit(code,language_name,translit,std,tscript,style,engvar)
 localtitle_t=lang_data.translit_title_table;-- table of transliteration standards and the language codes and scripts that apply to those standards
 localtitle_text='';-- tool tip text for title= attribute

 std=stdandstd:lower();-- lower case for table indexing

 ifnotis_set(std)andnotis_set(tscript)then-- when neither standard nor script specified
 title_text=language_name;-- write a generic tool tip
 ifnotmw.ustring.find(language_name,'languages',1,true)then-- collective language names (plural 'languages' is part of the name)
 title_text=substitute('1ドル-2ドル',{title_text,cfg.misc_text_t.language});-- skip this text (individual and macro languages only)
 end
 title_text=substitute('1ドル 2ドル',{title_text,mw.ustring.lower(cfg.engvar_t[engvar]['romanisz_lc'])});-- finish the tool tip; use romanization when neither script nor standard supplied

 elseifis_set(std)andis_set(tscript)then-- when both are specified
 iftitle_t[std]then-- and if standard is legitimate
 iftitle_t[std][tscript]then-- and if script for that standard is legitimate
 ifscript_table[tscript]then
 title_text=substitute('1ドル2ドル (3ドル 4ドル) 5ドル',{-- add the appropriate text to the tool tip
 title_text,
 title_t[std][tscript:lower()],
 script_table[tscript],
 cfg.make_translit_t.script,
 cfg.make_translit_t.transliteration,
 });
 else
 title_text=title_text..title_t[std]['default'];-- use the default if script not in std table; TODO: maint cat? error message because script not found for this standard?
 end
 else
 title_text=title_text..title_t[std]['default'];-- use the default if script not in std table; TODO: maint cat? error message because script not found for this standard?
 end
 else
 return'';-- invalid standard, setup for error message
 end

 elseifis_set(std)then-- translit-script not set, use language code
 ifnottitle_t[std]thenreturn'';end-- invalid standard, setup for error message

 iftitle_t[std][code]then-- if language code is in the table (xlit may not provide a language code)
 title_text=substitute('1ドル2ドル (3ドル 4ドル) 5ドル',{-- add the appropriate text to the tool tip
 title_text,
 title_t[std][code:lower()],
 language_name,
 cfg.misc_text_t.language,
 cfg.make_translit_t.transliteration,
 });
 else-- code doesn't match
 title_text=title_text..title_t[std]['default'];-- so use the standard's default
 end

 else-- here if translit-script set but translit-std not set
 iftitle_t['no_std'][tscript]then
 title_text=title_text..title_t['no_std'][tscript];-- use translit-script if set
 elseiftitle_t['no_std'][code]then
 title_text=title_text..title_t['no_std'][code];-- use language code
 else
 ifis_set(tscript)then
 title_text=substitute('1ドル2ドル-3ドル 4ドル',{-- write a script tool tip
 title_text,
 language_name,
 cfg.make_translit_t.script,
 cfg.make_translit_t.transliteration,
 });

 elseifis_set(code)then
 ifnotmw.ustring.find(language_name,'languages',1,true)then-- collective language names (plural 'languages' is part of the name)
 title_text=substitute('1ドル-2ドル',{-- skip this text (individual and macro languages only)
 title_text,
 cfg.misc_text_t.language,
 });
 end
 title_text=substitute('1ドル 2ドル',{-- finish the tool tip
 title_text,
 cfg.make_translit_t.transliteration,
 });
 else
 title_text=substitute('1ドル 2ドル',{-- generic tool tip (can we ever get here?)
 title_text,
 cfg.make_translit_t.transliteration,
 });
 end
 end
 end

 localtag
 ifis_set(code)then-- when a language code is provided (always with {{lang-??}} templates, not always with {{transliteration}})
 code=code:match('^(%a%a%a?)');-- strip all subtags leaving only the language subtag
 ifnotstylethen-- nil for the default italic style
 tag='<i lang="%s-Latn">%s</i>'
 else
 tag='<span style="font-style: %s" lang="%s-Latn">%s</span>'-- non-standard style, construct a span tag for it
 tag=string.format(tag,style,"%s","%s")
 end
 tag=string.format(tag,code,"%s")
 else
 tag='<span>%s</span>'-- when no language code: no lang= attribute, not italic ({{transliteration}} only)
 end

 tag=string.format(tag,translit)-- add the translit text
 if''==title_textthen-- when there is no need for a tool-tip
 returntag;-- done
 else
 title_text=cfg.engvar_sel_t.gb==engvarandtitle_text:gsub('([Rr]omani)z','%1s')ortitle_text;-- gb eng when engvar specifies gb eng; us eng else
 returntitle_wrapper_make(title_text,tag,'span');-- wrap with a tool-tip span and done
 end
 end


 --[[--------------------------< V A L I D A T E _ T E X T >----------------------------------------------------

 This function checks the content of args.text and returns empty string if nothing is amiss else it returns an
 error message. The tests are for empty or missing text and for improper or disallowed use of apostrophe markup.

 Italic rendering is controlled by the |italic= template parameter so italic markup should never appear in args.text
 either as ''itself'' or as '''''bold italic''''' unless |italic=unset or |italic=invert.

 ]]

 localfunctionvalidate_text(template,args)
 ifnotis_set(args.text)then
 returnmake_error_msg(cfg.validate_text_t.no_text,args,template);
 end

 ifargs.text:find("%f[\']\'\'\'\'%f[^\']")orargs.text:find("\'\'\'\'\'[\']+")then-- because we're looking, look for 4 appostrophes or 6+ appostrophes
 returnmake_error_msg(cfg.validate_text_t.malformed_markup,args,template);
 end

 localstyle=args.italic;

 if(cfg.keywords_t.unset~=style)and(cfg.keywords_t.invert~=style)then
 ifargs.text:find("%f[\']\'\'%f[^\']")orargs.text:find("%f[\']\'\'\'\'\'%f[^\']")then-- italic but not bold, or bold italic
 returnmake_error_msg(cfg.validate_text_t.italic_markup,args,template);
 end
 end
 end


 --[[--------------------------< R E N D E R _ M A I N T >------------------------------------------------------

 Render mainenance messages and categories.

 ]]

 localfunctionrender_maint(nocat)
 localmaint={};

 if0<#maint_msgsthen-- when there are maintenance messages
 table.insert(maint,table.concat({'<span class="lang-comment" style="font-style: normal; display: none; color: #33aa33; margin-left: 0.3em;">'}));-- opening <span> tag
 for_,msginipairs(maint_msgs)do
 table.insert(maint,table.concat({msg,' '}));-- add message strings
 end
 table.insert(maint,'</span>');-- close the span
 end

 if(0<#maint_cats)and(0==namespace)andnotnocatthen-- when there are maintenance categories; article namespace only
 for_,catinipairs(maint_cats)do
 table.insert(maint,table.concat({'[[Category:',cat,']]'}));-- format and add the categories
 end
 end

 returntable.concat(maint);
 end


 --[[--------------------------< P R O T O _ P R E F I X >------------------------------------------------------

 For proto languages, text is prefixed with a splat. We do that here as a flag for make_text_html() so that a splat
 will be rendered outside of italic markup (if used). If the first character in text here is already a splat, we
 do nothing.

 proto_param is boolean or nil; true adds splat prefix regardless of language name; false removes and inhibits
 regardless of language name; nil does nothing; presumes that the value in text is correct but removes extra splac.

 ]]

 localfunctionproto_prefix(text,language_name,proto_param)
 iffalse==proto_paramthen-- when forced by |proto=no
 returntext:gsub('^%**','');-- return text without splat prefix regardless of language name or existing splat prefix in text
 elseif(language_name:find('^Proto%-')or(true==proto_param))then-- language is a proto or forced by |proto=yes
 returntext:gsub('^%**','*');-- prefix proto-language text with a splat; also removes duplicate prefixing splats
 end

 returntext:gsub('^%*+','*');-- return text unmolested except multiple splats reduced to one splat
 end


 --[[--------------------------< H A S _ P O E M _ T A G >------------------------------------------------------

 Looks for a poem strip marker in text; returns true when found; false else.

 Auto-italic detection disabled when text has poem stripmarker because it is not possible for this code to know
 the content that will replace the stripmarker.

 ]]

 localfunctionhas_poem_tag(text)
 returntext:find('127円[^127円]*UNIQ%-%-poem%-[%a%d]+%-QINU[^127円]*127円')andtrueorfalse;
 end


 --[[--------------------------< H T M L _ T A G _ S E L E C T >------------------------------------------------

 Inspects content of and selectively trims text. Returns text and the name of an appropriate HTML tag for text.

 If text contains:
 	\n\n	text has implied <p>..</p> tags - trim leading and trailing whitespace and return 
 If text begins with list markup:
 	\n*		unordered
 	\n;		definition
 	\n:		definition
 	\n#		ordered
 trim all leading whitespace except \n and trim all trailing whitespace

 If text contains <poem>...</poem> stripmarker, return text unmodified and choose <div>..</div> tags because 
 the stripmarker is replaced with text wrapped in <div>..</div> tags.

 If the text contains any actual <div>...</div> tags, then it's again returned unmodified and <div>...</div>
 tags are used to wrap it, to prevent div/span inversion.

 ]]

 localfunctionhtml_tag_select(text)
 localtag;

 ifhas_poem_tag(text)then-- contains poem stripmarker (we can't know the content of that)
 tag='div';-- poem replacement is in div tags so lang must use div tags
 elseiftext:find('<div')then-- reductive; if the text contains a div tag, we must use div tags
 tag='div';
 elseifmw.text.trim(text):find('\n\n+')then-- contains implied p tags
 text=mw.text.trim(text);-- trim leading and trailing whitespace characters
 tag='div';-- must be div because span may not contain p tags (added later by MediaWiki); poem replacement is in div tags
 elseiftext:find('\n[%*:;%#]')then-- if text has list markup
 text=text:gsub('^[\t\r\f ]*',''):gsub('%s*$','');-- trim all whitespace except leading newline character '\n'
 tag='div';-- must be div because span may not contain ul, dd, dl, ol tags (added later by MediaWiki)
 else
 text=mw.text.trim(text);-- plain text
 tag='span';-- so span is fine
 end

 returntext,tag;
 end


 --[[--------------------------< V A L I D A T E _ P R O T O >--------------------------------------------------

 Validates value assigned to |proto=; permitted values are yes and no; yes returns as true, no returns as false,
 empty string (or parameter omitted) returns as nil; any other value returns nil with <proto_param> as second
 return value for use in error message.

 ]]

 localfunctionvalidate_proto(proto_param)
 ifcfg.keywords_t.affirmative==proto_paramthen
 returntrue;
 elseifcfg.keywords_t.negative==proto_paramthen
 returnfalse;
 elseifis_set(proto_param)then
 returnnil,proto_param;-- |proto= something other than 'yes' or 'no'
 else
 returnnil;-- missing or empty
 end
 end


 --[[--------------------------< L A N G U A G E _ N A M E _ G E T >--------------------------------------------

 Common function to return language name from the data set according to IETF tag.

 Returns language name if found in data tables; nil else.

 ]]

 localfunctionlanguage_name_get(ietf,code,cat)
 ietf=ietf:lower();-- ietf:lower() because format_ietf_tag() returns mixed case

 localname;-- remains nil if not found

 ifoverride_table[ietf]then-- look for whole IETF tag in override table
 name=override_table[ietf];
 elseifoverride_table[code]then-- not there so try basic language tag
 name=override_table[code];
 elseiflang_table[code]then-- shift to IANA active tag/name table
 name=lang_table[code];
 elseiflang_dep_table[code]then-- try the IANA deprecated tag/name table
 name=lang_dep_table[code];
 end

 iflang_dep_table[code]andcatthen-- because deprecated code may have been overridden to en.wiki preferred name
 table.insert(maint_cats,substitute(cfg.language_name_get_t.deprecated_cat,{code}));
 table.insert(maint_msgs,substitute(cfg.language_name_get_t.deprecated_msg,{code}));
 end

 returnname;-- name from data tables or nil
 end


 --[[--------------------------< T E X T _ S C R I P T _ M A T C H _ T E S T >----------------------------------

 IETF script subtag should match the script of the <text>. This module does not attempt to know all scripts and
 what they look like. It does know what Latn script looks like so when <text> is written using other than the Latn
 script, the IETF script subtag, if present, should not be Latn.

 Conversely, when <text> is written using the Latn script, the IETF script subtag, if present, should be Latn.

 For the purposes of this test, Latf (Fraktur) and Latg (Gaelic) are considered to be equivalent to Latn because
 unicode treats these two scripts as font-specific variants of Latn.

 Returns an error message when mismatch detected; nil else.

 ]]

 localfunctiontext_script_match_test(script,is_latn_text,pos,char)
 localscripts_t={['latf']=true,['latg']=true,['latn']=true};-- unicode 'latn' scripts; 'latf' and 'latg' are font variants so there are no Fraktur or Gaelic codepoints
 ifis_set(script)then-- don't bother with the rest of this if <script> is nil or empty string
 script=script:lower();-- lower case to index into <scripts_t>
 ifis_latn_textthen-- when text is wholly Latn script
 ifnotscripts_t[script]then-- but a non-Latn script is specified
 returncfg.text_script_match_test_t.latn_txt_mismatch;-- emit an error message
 end
 else-- when text is not wholly Latn script
 ifscripts_t[script]then-- but a Latn script is specified
 returnsubstitute(cfg.text_script_match_test_t.latn_scr_mismatch,{pos,char});-- emit an error message with position of first offending character
 end
 end
 end
 end


 --[[--------------------------< B I N A R Y _ S E A R C H >---------------------------------------------------

 conducts a binary search of <ranges_t> for a sub-range that holds <target>.

 returns boolean true if a sub-range holding <target> is found; boolean false else.

 ]]

 localfunctionbinary_search(target,ranges_t)
 localidx_bot=1;-- initialize to index of first key
 localidx_top=sizeof_ranges_t;-- initialize to index of last key (number of keys)

 if(target<ranges_t[idx_bot][1])or(target>ranges_t[idx_top][2])then-- invalid; target out of range
 return;-- abandon
 end

 localidx_mid;-- calculated index of range midway between top index and bottom index
 localflag=false;-- flag to tell us when we've evaluated last (highest) range in <ranges_t>

 while1do
 idx_mid=math.ceil((idx_bot+idx_top)/2);-- get the mid-point in the <ranges_t> sequence
 if(target>=ranges_t[idx_mid][1])and(target<=ranges_t[idx_mid][2])then-- indexed range low value <= target <= indexed range high value
 returntrue;-- we found the range that holds the <target> character; return true

 elseif(target>ranges_t[idx_mid][2])then-- is <target> > indexed range high value?
 idx_bot=idx_mid;-- adjust <idx_bot> up

 else-- here when <target> less than indexed range low value
 idx_top=idx_mid-1;-- adjust <idx_top> down
 end

 ifflagthen
 break;-- here when we just evaluated the last range and <target> not found
 end

 ifnotflagand(idx_bot==idx_top)then-- set true just before we evaluate the last (highest) range in <ranges_t>
 flag=true;
 end
 end
 end


 --[[--------------------------< I S _ L A T I N >--------------------------------------------------------------

 compare <text> as codepoints to lists of known codepoints accepted as Latn script

 returns boolean true and modified <text> when <text> is wrapped in accept-as-written markup

 returns boolean true and <text> when codepoint is known

 returns boolean false, <text>, non-Latn codepoint position in <text> (left to right), and the codepoint character
 	when codepoint is not known

 TODO: when text has accept-as-written markup, return a non-boolean value to indicate that <text> is not wholly
 	latn script? Use that return value to create non-Latn HTML lang= attribute because <text> isn't really
 	latn so lang=und (undetermined)? or instead, omit the -Latn subtag? (without -Latn need to force |italic=yes)

 ]]

 localfunctionis_latin(text,tag)
 localcount;
 text,count=text:gsub('^%(%((.+)%)%)$','%1');-- remove accept-as-written markup if present
 if0~=countthen
 returntrue,text;-- markup present so assume that <text> is Latn-script
 end

 localpos=0;-- position counter for error messaging
 forcodepointinmw.ustring.gcodepoint(text)do-- fetch each code point
 pos=pos+1;-- bump the position counter

 ifnotis_latn_data.singles_t[codepoint]and-- codepoint not found in the singles list?
 notbinary_search(codepoint,is_latn_data.ranges_t)and-- codepoint not a member of a listed range?
 not(tagandis_latn_data.specials_t[codepoint]andis_latn_data.specials_t[codepoint][tag])then-- not a language-specific codepoint?
 returnfalse,text,pos,mw.ustring.char(codepoint);-- codepoint not known; return false with codepoint position and character representation
 end
 end
 returntrue,text;-- is known; return <text>
 end


 --[[--------------------------< _ L A N G >--------------------------------------------------------------------

 Entry point for {{lang}}.

 There should be no reason to set parameters in the {{lang}} {{#invoke:}}
 	<includeonly>{{#invoke:lang|lang}}</includeonly>

 Parameters are received from the template's frame (parent frame).

 ]]

 localfunction_lang(args)
 localout={};
 locallanguage_name;-- used to make category names
 localcategory_name;-- same as language_name except that it retains any parenthetical disambiguators (if any) from the data set
 localsubtags={};-- IETF subtags script, region, variant, and private
 localcode;-- the language code
 localmsg;-- for error messages
 localtag='span';-- initial value for make_text_html()
 localtemplate=args.templateorcfg.templates_t.lang;

 maint_cats={};-- initialize because when this module required into another module, these only declared once so only initialzed once
 maint_msgs={};

 validate_cat_args(args);-- determine if categorization should be suppressed

 ifargs[1]andargs.codethen
 returnmake_error_msg(substitute(cfg.lang_t.conflict_n_param,{'1',cfg.lang_t.conflict_n_param_types.code}),args,template);
 else
 args.code=args[1]orargs.code;-- prefer args.code
 end

 ifargs[2]andargs.textthen
 returnmake_error_msg(substitute(cfg.lang_t.conflict_n_param,{'2',cfg.lang_t.conflict_n_param_types.text}),args,template);
 else
 args.text=args[2]orargs.text;-- prefer args.text
 end

 msg=validate_text(template,args);-- ensure that |text= is set
 ifis_set(msg)then-- msg is an already-formatted error message
 returnmsg;
 end

 args.text,tag=html_tag_select(args.text);-- inspects text; returns appropriate HTML tag with text trimmed accordingly

 args.rtl=args.rtl==cfg.keywords_t.affirmative;-- convert to boolean: 'yes' -> true, other values -> false

 args.proto,msg=validate_proto(args.proto);-- return boolean, or nil, or nil and error message flag
 ifmsgthen
 returnmake_error_msg(substitute(cfg.lang_t.invalid_proto,{msg}),args,template);
 end

 code,subtags.script,subtags.region,subtags.variant,subtags.private,msg=get_ietf_parts(args.code);-- |script=, |region=, |variant= not supported because they should be part of args.code ({{{1}}} in {{lang}})

 ifmsgthen
 returnmake_error_msg(msg,args,template);
 end

 localis_latn_text,pos,char;
 is_latn_text,args.text,pos,char=is_latin(args.text,code);-- make a boolean

 msg=text_script_match_test(subtags.script,is_latn_text,pos,char)
 ifmsgthen-- if an error detected then there is an error message
 returnmake_error_msg(msg,args,template);
 end

 args.italic,msg=validate_italic(args);
 ifmsgthen
 returnmake_error_msg(msg,args,template);
 end

 ifnil==args.italicthen-- nil when |italic= absent or not set or |italic=default; args.italic controls
 if('latn'==subtags.script)or-- script is latn
 (this_wiki_lang_tag~=codeandnotis_set(subtags.script)andnothas_poem_tag(args.text)andis_latn_text)then-- text not this wiki's language, no script specified and not in poem markup but is wholly latn script (auto-italics)
 args.italic='italic';-- DEFAULT for {{lang}} templates is upright; but if latn script set for font-style:italic
 else
 args.italic='inherit';-- italic not set; script not latn; inherit current style
 end
 end

 ifis_set(subtags.script)then-- if script set, override rtl setting
 ifin_array(subtags.script,lang_data.rtl_scripts)then
 args.rtl=true;-- script is an rtl script
 else
 args.rtl=false;-- script is not an rtl script
 end
 end

 args.code=format_ietf_tag(code,subtags.script,subtags.region,subtags.variant,subtags.private);-- format to recommended subtag styles
 language_name=language_name_get(args.code,code,true);-- get language name; try IETF tag first, then code w/o variant then code w/ variant

 ifcfg.keywords_t.invert==args.italicand'span'==tagthen-- invert only supported for in-line content
 args.text=invert_italics(args.text)
 end

 args.text=proto_prefix(args.text,language_name,args.proto);-- prefix proto-language text with a splat

 table.insert(out,make_text_html(args.code,args.text,tag,args.rtl,args.italic,args.size,language_name));
 table.insert(out,make_category(code,language_name,args.nocat));
 table.insert(out,render_maint(args.nocat));-- maintenance messages and categories

 returntable.concat(out);-- put it all together and done
 end


 --[[--------------------------< L A N G >----------------------------------------------------------------------

 Entry point for {{lang}}.

 There should be no reason to set parameters in the {{lang}} {{#invoke:}}
 	<includeonly>{{#invoke:lang|lang}}</includeonly>

 Parameters are received from the template's frame (parent frame).

 ]]

 localfunctionlang(frame)
 localargs_t=getArgs(frame,{-- this code so that we can detect and handle wiki list markup in text
 valueFunc=function(key,value)
 if2==keyor'text'==keythen-- the 'text' parameter; do not trim wite space
 returnvalue;-- return untrimmed 'text'
 elseifvaluethen-- all other values: if the value is not nil
 value=mw.text.trim(value);-- trim whitespace
 if''~=valuethen-- empty string when value was only whitespace
 returnvalue;
 end
 end
 returnnil;-- value was empty or contained only whitespace
 end-- end of valueFunc
 });

 args_t.fn=nil;-- unset because not supported but this function might have been called by {{lang|fn=lang|...}}

 localmsg=parameter_validate(args_t,cfg.templates_t.lang);-- verify that all supplied parameters are supported by {{lang-??}}
 ifmsgthen
 returnmake_error_msg(msg,args_t,cfg.templates_t.lang);-- when template has unsupported params, abandon with error message
 end

 return_lang(args_t);
 end


 --[[--------------------------< T R A N S L A T I O N _ M A K E >----------------------------------------------

 Stand-alone function to create literal translation of main text.

 Also used by {{lang-x2}}.

 ]]

 localfunctiontranslation_make(args_t)
 localtranslation_t={', '};-- initialize output

 if'none'~=args_t.labelthen-- if we want a label
 table.insert(translation_t,'<small>');-- open the <small> HTML tag
 ifcfg.keywords_t.negative==args_t.linkthen
 table.insert(translation_t,substitute('<abbr title="1ドル">2ドル</abbr>',{cfg.translation_make_t.lit_xlation,cfg.translation_make_t.lit_abbr}));-- unlinked form
 else
 table.insert(translation_t,make_wikilink(cfg.translation_make_t.lit_xlation,cfg.translation_make_t.lit_abbr));-- linked form
 end
 table.insert(translation_t,"&thinsp;</small>");-- close the <small> HTML tag
 end
 table.insert(translation_t,table.concat({'&#39;',args_t.translation,'&#39;'}));-- use HTML entities to avoid wiki markup confusion
 returntable.concat(translation_t);-- make a big string and done
 end


 --[[--------------------------< _ L A N G _ X X >--------------------------------------------------------------

 For the {{lang-??}} templates, the only parameter required to be set in the template is the language code. All
 other parameters can, usually should, be written in the template call. For {{lang-??}} templates for languages
 that can have multiple writing systems, it may be appropriate to set |script= as well.

 For each {{lang-??}} template choose the appropriate entry-point function so that this function knows the default
 styling that should be applied to text.

 For normal, upright style:
 	<includeonly>{{#invoke:lang|lang_xx_inherit|code=xx}}</includeonly>
 For italic style:
 	<includeonly>{{#invoke:lang|lang_xx_italic|code=xx}}</includeonly>

 All other parameters should be received from the template's frame (parent frame)

 Supported parameters are:
 	|code = (required) the IANA language code
 	|script = IANA script code; especially for use with languages that use multiple writing systems
 	|region = IANA region code
 	|variant = IANA variant code
 	|text = (required) the displayed text in language specified by code
 	|link = boolean false ('no') does not link code-spcified language name to associated language article
 	|rtl = boolean true ('yes') identifies the language specified by code as a right-to-left language
 	|nocat = boolean true ('yes') inhibits normal categorization; error categories are not affected
 	|cat = boolian false ('no') opposite form of |nocat=
 	|italic = boolean true ('yes') renders displayed text in italic font; boolean false ('no') renders displayed text in normal font; not set renders according to initial_style_state
 	|lit = text that is a literal translation of text
 	|label = 'none' to suppress all labeling (language name, 'translit.', 'lit.')
 				any other text replaces language-name label - automatic wikilinking disabled

 	for those {{lang-??}} templates that support transliteration (those templates where |text= is not entirely latn script):
 	|translit = text that is a transliteration of text
 	|translit-std = the standard that applies to the transliteration
 	|translit-script = ISO 15924 script name; falls back to code

 For {{lang-??}}, the positional parameters are:
 	{{{1}}}	text
 	{{{2}}}	transliterated text
 	{{{3}}}	literal translation text
 no other positional parameters are allowed

 ]]

 localfunction_lang_xx(args,base_template)-- base_template will be either of 'langx' or 'lang-xx'
 localout={};
 locallanguage_name;-- used to make display text, article links
 localcategory_name;-- same as language_name except that it retains any parenthetical disambiguators (if any) from the data set
 localsubtags={};-- IETF subtags script, region, and variant
 localcode;-- the language code

 localtranslit_script_name;-- name associated with IANA (ISO 15924) script code
 localtranslit;
 localmsg;-- for error messages
 localtag='span';-- initial value for make_text_html()
 localtemplate=args.templateorbase_template;

 maint_cats={};-- initialize because when this module required into another module, these only declared once so only initialzed once
 maint_msgs={};

 localtext_idx=(cfg.templates_t.langx==base_template)and2or1;-- for {{langx}} 'text' positional parameter is '2'
 localtranslit_idx=(cfg.templates_t.langx==base_template)and3or2;
 localxlate_idx=(cfg.templates_t.langx==base_template)and4or3;

 ifargs[text_idx]andargs.textthen
 returnmake_error_msg(substitute(cfg.lang_t.conflict_n_param,{text_idx,cfg.lang_t.conflict_n_param_types.text}),args,template);
 else
 args.text=args[text_idx]orargs.text;-- prefer positional 'text' parameter
 end

 msg=validate_text(template,args);-- ensure that |text= is set, does not contain italic markup and is protected from improper bolding
 ifis_set(msg)then
 returnmsg;
 end

 args.text,tag=html_tag_select(args.text);-- inspects text; returns appropriate HTML tag with text trimmed accordingly

 ifargs[translit_idx]andargs.translitthen
 returnmake_error_msg(substitute(cfg.lang_t.conflict_n_param,{translit_idx,cfg.lang_t.conflict_n_param_types.translit}),args,template);

 else
 args.translit=args[translit_idx]orargs.translit-- prefer positional 'translit' parameter
 end

 args.engvar=cfg.engvar_sel_t[args.engvar]orcfg.default_engvar;-- |engvar= when valid; cfg.default_engvar else

 ifargs[xlate_idx]and(args.translationorargs.lit)then
 returnmake_error_msg(substitute(cfg.lang_xx_t.conflict_n_lit,{xlate_idx}),args,template);
 elseifargs.translationandargs.litthen
 returnmake_error_msg(cfg.lang_xx_t.conflict_lit,args,template);
 else
 args.translation=args[xlate_idx]orargs.translationorargs.lit;-- prefer positional 'translation' parameter
 end

 ifargs.linksandargs.linkthen
 returnmake_error_msg(cfg.lang_xx_t.conflict_link,args,template);
 else
 args.link=args.linkorargs.links;-- prefer args.link
 end

 validate_cat_args(args);-- determine if categorization should be suppressed

 args.rtl=args.rtl==cfg.keywords_t.affirmative;-- convert to boolean: 'yes' -> true, other values -> false

 code,subtags.script,subtags.region,subtags.variant,subtags.private,msg=get_ietf_parts(args.code,args.script,args.region,args.variant);-- private omitted because private

 ifmsgthen-- if an error detected then there is an error message
 returnmake_error_msg(msg,args,template);
 end

 ifargs.translitthen
 locallatn,pos,char;
 latn,args.translit,pos,char=is_latin(args.translit,((''~=subtags.private)and(code..'-x-'..subtags.private))orcode);
 ifnotlatnthen
 returnmake_error_msg(substitute(cfg.lang_xx_t.translit_nonlatn,{pos,char}),args,template);
 end
 end

 localis_latn_text,text,pos,char=is_latin(args.text,code);-- make a boolean
 args.text=text;-- may have been modified (accept-as-written markup removed)

 msg=text_script_match_test(subtags.script,is_latn_text,pos,char)
 ifmsgthen-- if an error detected then there is an error message
 returnmake_error_msg(msg,args,template);
 end

 args.italic,msg=validate_italic(args);
 ifmsgthen
 returnmake_error_msg(msg,args,template);
 end

 ifcfg.templates_t.langx==base_templatethen-- auto-italics for {{langx}} templates; adapted from {{lang}} (no support for poem tag) 
 ifnil==args.italicthen-- nil when |italic= absent or not set or |italic=default; args.italic controls
 if('latn'==subtags.script)or-- script is latn
 (this_wiki_lang_tag~=codeandnotis_set(subtags.script)andis_latn_text)then-- text is not this wiki's language, no script specified and is wholly latn script (auto-italics)
 args.italic='italic';-- set font-style:italic
 else
 args.italic='inherit';-- italic not set; script not latn; inherit current style
 end
 end

 else-- {{lang-xx}} does not do auto italics; retained for those wikis that don't support {{langx}}
 ifnil==args.italicthen-- args.italic controls
 ifis_set(subtags.script)then
 if'latn'==subtags.scriptthen
 args.italic='italic';-- |script=Latn; set for font-style:italic
 else
 args.italic=initial_style_state;-- italic not set; script is not latn; set for font-style:<initial_style_state>
 end
 else
 args.italic=initial_style_state;-- here when |italic= and |script= not set; set for font-style:<initial_style_state>
 end
 end
 end

 ifis_set(subtags.script)then-- if script set override rtl setting
 ifin_array(subtags.script,lang_data.rtl_scripts)then
 args.rtl=true;-- script is an rtl script
 else
 args.rtl=false;-- script is not an rtl script
 end
 end

 args.proto,msg=validate_proto(args.proto);-- return boolean, or nil, or nil and error message flag
 ifmsgthen
 returnmake_error_msg(substitute(cfg.lang_t.invalid_proto,{args.proto}),args,template);
 end

 args.code=format_ietf_tag(code,subtags.script,subtags.region,subtags.variant,subtags.private);-- format to recommended subtag styles
 language_name=language_name_get(args.code,code,true);-- get language name; try IETF tag first, then code w/o variant then code w/ variant

 category_name=language_name;-- category names retain IANA parenthetical diambiguators (if any)
 language_name=language_name:gsub('%s+%b()','');-- remove IANA parenthetical disambiguators or qualifiers from names that have them

 ifargs.labelthen
 if'none'~=args.labelthen
 table.insert(out,table.concat({args.label,': '}));-- custom label
 end
 else
 ifcfg.keywords_t.negative==args.linkthen
 table.insert(out,language_name);-- language name without wikilink
 else
 ifmw.ustring.find(language_name,'languages',1,true)then
 table.insert(out,make_wikilink(language_name));-- collective language name uses simple wikilink
 elseiflang_data.article_name[args.code:lower()]then-- is IETF tag in article name over ride?
 table.insert(out,make_wikilink(lang_data.article_name[args.code:lower()],language_name));-- language name with wikilink from override data
 elseiflang_data.article_name[code]then-- is language tag in article override
 table.insert(out,make_wikilink(lang_data.article_name[code],language_name));-- language name with wikilink from override data
 else
 table.insert(out,make_wikilink(substitute('1ドル 2ドル',{language_name,cfg.misc_text_t.language}),language_name));-- language name with wikilink
 end
 end
 table.insert(out,': ');-- separator
 end

 ifcfg.keywords_t.invert==args.italicthen
 args.text=invert_italics(args.text)
 end

 args.text=proto_prefix(args.text,language_name,args.proto);-- prefix proto-language text with a splat

 table.insert(out,make_text_html(args.code,args.text,tag,args.rtl,args.italic,args.size,('none'==args.label)andlanguage_nameornil))

 ifis_set(args.translit)andnotis_latn_textthen-- transliteration; not supported when args.text is wholly latn text (this is an imperfect test)
 table.insert(out,', ');-- comma to separate text from translit
 if'none'~=args.labelthen
 table.insert(out,'<small>');
 ifscript_table[args['translit-script']]then-- when |translit-script= is set, try to use the script's name
 translit_script_name=script_table[args['translit-script']];
 else
 translit_script_name=language_name;-- fall back on language name
 end

 localtranslit_title_obj=mw.title.makeTitle(0,substitute('1ドル 2ドル',{cfg.lang_xx_t.romanization,translit_script_name}));-- make a title object; no engvar, article titles use US spelling
 iftranslit_title_obj.existsand(cfg.keywords_t.negative~=args.link)then
 table.insert(out,make_wikilink(substitute('1ドル 2ドル',{cfg.lang_xx_t.romanization,translit_script_nameorlanguage_name}),
 substitute('1ドル',{cfg.engvar_t[args.engvar]['romanisz_pt']}))..':');-- make a wikilink if there is an article to link to; engvar the display text

 else
 table.insert(out,substitute('1ドル:',{cfg.engvar_t[args.engvar]['romanisz_pt']}));-- else plain text per engvar

 end
 table.insert(out,'&nbsp;</small>');-- close the small tag
 end

 translit=make_translit(args.code,language_name,args.translit,args['translit-std'],args['translit-script'],nil,args.engvar)
 ifis_set(translit)then
 table.insert(out,translit);
 else
 returnmake_error_msg(substitute('1ドル: 2ドル',{cfg.lang_xx_t.invalid_xlit_std,args['translit-std']or'[missing]'}),args,template);
 end

 elseifis_set(args.translit)andis_latn_textthen-- when creating a transliteration of Latn script <text>
 returnmake_error_msg(cfg.lang_xx_t.xlit_of_latn,args,template);-- emit error message and abandon
 end

 ifis_set(args.translation)then-- translation (not supported in {{lang}})
 table.insert(out,translation_make(args));
 end

 table.insert(out,make_category(code,category_name,args.nocat));
 table.insert(out,render_maint(args.nocat));-- maintenance messages and categories

 returntable.concat(out);-- put it all together and done
 end


 --[[--------------------------< L A N G _ X X _ A R G S _ G E T >----------------------------------------------

 Common function to get args table from {{lang-??}} templates.

 Returns table of args.

 Text positional parameters are not trimmed here but are selectively trimmed at html_tag_select().

 ]]

 localfunctionlang_xx_args_get(frame,base_template)
 localargs_t=getArgs(frame,
 {
 parentFirst=true,-- parameters in the template override parameters set in the {{#invoke:}}
 valueFunc=function(key,value)
 if((cfg.templates_t.langx==base_template)and2or1)==keythen-- the 'text' positional parameter; 1 for {{lang-??}}, 2 for {{langx}}; do not trim wite space
 returnvalue;-- return untrimmed 'text' positional parameter
 elseifvaluethen-- all other values: if the value is not nil
 value=mw.text.trim(value);-- trim whitespace
 if''~=valuethen-- empty string when value was only whitespace
 returnvalue;
 end
 end
 returnnil;-- value was empty or contained only whitespace
 end-- end of valueFunc
 });

 returnargs_t;
 end


 --[[--------------------------< L A N G _ X X _ I T A L I C >--------------------------------------------------

 Entry point for those {{lang-??}} templates that call lang_xx_italic(). Sets the initial style state to italic.

 ]]

 localfunctionlang_xx_italic(frame)
 localargs=lang_xx_args_get(frame,cfg.templates_t.langxx);
 args.fn=nil;-- unset because not supported but this function might have been called by {{lang|fn=lang_xx_italic|...}}

 localmsg=parameter_validate(args,cfg.templates_t.langxx);-- verify that all supplied parameters are supported by {{lang-??}}
 ifmsgthen
 returnmake_error_msg(msg,args,cfg.templates_t.langxx);-- when template has unsupported params, abandon with error message
 end

 initial_style_state='italic';
 return_lang_xx(args,cfg.templates_t.langxx)..'[[Category:Pages using Lang-xx templates]]';-- temporary category
 end


 --[[--------------------------< _ L A N G _ X X _ I T A L I C >------------------------------------------------

 Entry point from another module. Sets the initial style state to italic.

 ]]

 localfunction_lang_xx_italic(args)
 initial_style_state='italic';
 return_lang_xx(args,cfg.templates_t.langxx);
 end


 --[[--------------------------< L A N G _ X X _ I N H E R I T >------------------------------------------------

 Entry point for those {{lang-??}} templates that call lang_xx_inherit(). Sets the initial style state to inherit.

 ]]

 localfunctionlang_xx_inherit(frame)
 localargs=lang_xx_args_get(frame,cfg.templates_t.langxx);
 args.fn=nil;-- unset because not supported but this function might have been called by {{lang|fn=lang_xx_inherit|...}}

 localmsg=parameter_validate(args,cfg.templates_t.langxx);-- verify that all supplied parameters are supported by {{lang-??}}
 ifmsgthen
 returnmake_error_msg(msg,args,cfg.templates_t.langxx);-- when template has unsupported params, abandon with error message
 end

 initial_style_state='inherit';
 return_lang_xx(args,cfg.templates_t.langxx)..'[[Category:Pages using Lang-xx templates]]';-- temporary category
 end


 --[[--------------------------< _ L A N G _ X X _ I N H E R I T >----------------------------------------------

 Entry point from another module. Sets the initial style state to inherit.

 ]]

 localfunction_lang_xx_inherit(args)
 initial_style_state='inherit';
 return_lang_xx(args,cfg.templates_t.langxx);
 end


 --[[--------------------------< _ L A N G X >------------------------------------------------------------------

 Entry point from another module.

 ]]

 localfunction_langx(args_t)
 locallangx_data=mw.loadData('Module:Lang/langx');-- get necessary data 
 localrtl_t=langx_data.rtl_t;-- get list of language tags for languages that are rendered right-to-left
 locallink_t=langx_data.link_t;-- get list of language tags for {{lang-??}} templates that set |link=<something>
 localsize_t=langx_data.size_t;-- get list of language tags for {{lang-??}} templates that set |size=<something>

 localmsg=parameter_validate(args_t,cfg.templates_t.langx);
 ifmsgthen
 returnmake_error_msg(msg,args_t,cfg.templates_t.langx);
 end

 args_t.code=args_t[1]orargs_t.code;-- get the language tag; must be {{{1}}} or |code=
 ifnotargs_t.codethen
 returnmake_error_msg(cfg.get_ietf_parts_t.missing_lang_tag,args_t,cfg.templates_t.langx);
 end

 args_t.rtl=args_t.rtlor(rtl_t[args_t.code]andcfg.keywords_t.affirmative);-- prefer |rtl= in template call, use rtl_t else
 args_t.link=args_t.linkorlink_t[args_t.code];-- prefer |link= in template call, use link_t felse
 args_t.size=args_t.sizeorsize_t[args_t.code];-- prefer |size= in template call, use size_t else

 args_t[1]=nil;-- unset to mimic {{lang-??}} templates which set |code=xx

 locallang_subtag=args_t.code;-- use only the base language subtag for unsupported tag test; some args_t.code are modified by |script= etc
 return_lang_xx(args_t,cfg.templates_t.langx);
 end


 --[[--------------------------< L A N G X >--------------------------------------------------------------------

 Entry point for {{langx}}.

 this function calls _lang_xx() to render non-English text. The {{lang-??}} templates have three positional paramters
 but {{langx}} has four:

 				| 1	| 2		| 3		| 4	
 	{{lang-xx	|<text>	|<xlit>		|<xlat>		}}
 	{{langx		|<tag>	|<text>		|<xlit>		|<xlat>		}}

 The calls to lang_xx_args_get() and _lang_xx() use 'langx' as a flag for those functions to select the proper
 positional parameters.

 {{lang-??}} depends on the calling template to select 'inherit' or 'italic' to establish the default rendering.

 {{langx}} can't do that. The initial version of {{langx}} relied on a list of language tags (inherit_t in ~/langx)
 scraped from those {{lang-??}} templates that call lang_xx_inherit() to render text in upright font. langx() now
 uses auto-italics code adapted from {{lang}} (doesn't support poem tags).

 ]]

 localfunctionlangx(frame)
 localargs_t=lang_xx_args_get(frame,cfg.templates_t.langx);-- get the arguments; 'langx' is the <base_template> used to decide which positional param is 'text', 'translit', 'lit'

 return_langx(args_t);
 end


 --[[--------------------------< _ I S _ I E T F _ T A G >------------------------------------------------------

 Returns true when a language name associated with IETF language tag exists; nil else. IETF language tag must be valid.

 All code combinations supported by {{lang}} and the {{lang-??}} templates are supported by this function.

 Module entry point from another module.

 ]]

 localfunction_is_ietf_tag(tag)-- entry point when this module is require()d into another
 localc,s,r,v,p,err;-- code, script, region, variant, private, error message
 c,s,r,v,p,err=get_ietf_parts(tag);-- disassemble tag into constituent part and validate

 return((candnoterr)andtrue)ornil;-- return true when code portion has a value without error message; nil else
 end


 --[[--------------------------< I S _ I E T F _ T A G >--------------------------------------------------------

 Module entry point from an {{#invoke:}}.

 ]]

 localfunctionis_ietf_tag(frame)
 return_is_ietf_tag(getArgs(frame)[1]);-- args[1] is the IETF language tag to be tested; also get parent frame
 end


 --[[--------------------------< I S _ I E T F _ T A G _ F R A M E >--------------------------------------------

 Module entry point from an {{#invoke:}}; same as is_ietf_tag() except does not get parameters from the parent
 (template) frame. This function not useful when called by {{lang|fn=is_ietf_tag_frame|<tag>}} because <tag>
 is in the parent frame.

 ]]

 localfunctionis_ietf_tag_frame(frame)
 return_is_ietf_tag(getArgs(frame,{frameOnly=true,})[1]);-- args[1] is the IETF language tag to be tested; do not get parent frame
 end


 --[[--------------------------< _ N A M E _ F R O M _ T A G >--------------------------------------------------

 Returns language name associated with IETF language tag if valid; error message else.

 All code combinations supported by {{lang}} and the {{lang-??}} templates are supported by this function.

 Set invoke's |link= parameter to yes to get wikilinked version of the language name.

 Module entry point from another module.

 ]]

 localfunction_name_from_tag(args)
 localsubtags={};-- IETF subtags script, region, variant, and private
 localraw_code=args[1];-- save a copy of the input IETF subtag
 locallink=cfg.keywords_t.affirmative==args['link'];-- make a boolean
 locallabel=args.label;
 localcode;-- the language code
 localmsg;-- gets an error message if IETF language tag is malformed or invalid
 locallanguage_name='';

 code,subtags.script,subtags.region,subtags.variant,subtags.private,msg=get_ietf_parts(raw_code);
 ifmsgthen
 localtemplate=(args['template']andtable.concat({'{{',args['template'],'}}: '}))or'';-- make template name (if provided by the template)
 returnmake_error_span(template,msg);
 end

 raw_code=format_ietf_tag(code,subtags.script,subtags.region,subtags.variant,subtags.private);-- format to recommended subtag styles; private omitted because private
 language_name=language_name_get(raw_code,code);-- get language name; try IETF tag first, then code w/o variant then code w/ variant

 if'yes'~=args.rawthen
 language_name=language_name:gsub('%s+%b()','');-- remove IANA parenthetical disambiguators or qualifiers from names that have them
 end

 iflinkthen-- when |link=yes, wikilink the language name
 ifmw.ustring.find(language_name,'languages',1,true)then
 language_name=make_wikilink(language_name,label);-- collective language name uses simple wikilink
 elseiflang_data.article_name[raw_code:lower()]then-- is IETF tag in article name override?
 language_name=make_wikilink(lang_data.article_name[raw_code:lower()],labelorlanguage_name);-- language name with wikilink from override data
 elseiflang_data.article_name[code]then-- is language tag in article name override?
 language_name=make_wikilink(lang_data.article_name[code],labelorlanguage_name);-- language name with wikilink from override data
 else
 language_name=make_wikilink(substitute('1ドル 2ドル',{language_name,cfg.misc_text_t.language}),labelorlanguage_name);-- language name with wikilink
 end
 end

 returnlanguage_name;
 end


 --[[--------------------------< N A M E _ F R O M _ T A G >----------------------------------------------------

 Module entry point from an {{#invoke:}}.

 ]]

 localfunctionname_from_tag(frame)-- entry point from an {{#invoke:lang|name_from_tag|<IETF tag>|link=<yes>|template=<template name>}}
 return_name_from_tag(getArgs(frame))-- pass-on the args table, nothing else; getArgs() so we also get parent frame
 end


 --[[--------------------------< _ T A G _ F R O M _ N A M E >--------------------------------------------------

 Returns the IETF language tag associated with the language name. Spelling of language name must be correct
 according to the spelling in the source tables. When a standard language name has a parenthetical disambiguator,
 that disambiguator must be omitted (they are not present in the data name-to-tag tables).

 Module entry point from another module.

 ]]

 localfunction_tag_from_name(args)-- entry point from another module
 localmsg;

 ifargs[1]and''~=args[1]then
 localdata=mw.loadData('Module:Lang/tag from name');-- get the reversed data tables TODO: change when going live
 locallang=args[1]:lower();-- allow any-case for the language name (speeling must till be correct)
 localtag=data.rev_override_table[lang]ordata.rev_lang_table[lang]ordata.rev_lang_dep_table[lang];-- get the code; look first in the override then in the standard

 iftagthen
 returntag,true;-- language name found so return tag and done; second return used by is_lang_name()
 else
 msg=substitute(cfg.tag_from_name_t.lang_not_found,{args[1]});-- language name not found, error message
 end
 else
 msg=cfg.tag_from_name_t.missing_lang_name;-- language name not found, error message
 end

 localtemplate='';
 ifargs.templateand''~=args.templatethen
 template=table.concat({'{{',args['template'],'}}: '});-- make template name (if provided by the template)
 end
 returnmake_error_span(template,msg);

 end


 --[[--------------------------< T A G _ F R O M _ N A M E >----------------------------------------------------

 Module entry point from an {{#invoke:}}.

 ]]

 localfunctiontag_from_name(frame)-- entry point from an {{#invoke:lang|tag_from_name|<language name>|link=<yes>|template=<template name>}}
 localresult,_=_tag_from_name(getArgs(frame))-- pass-on the args table, nothing else; getArgs() so we also get parent frame; supress second return used by is_lang_name()
 returnresult;
 end


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

 Module entry point from an {{#invoke:}}.

 ]]

 localfunctionis_lang_name(frame)
 local_,result=_tag_from_name(getArgs(frame))-- pass-on the args table, nothing else; getArgs() so we also get parent frame; supress second return used by tag_from_name()
 returnresultandtrueornil;
 end


 --[[--------------------------< _ X L I T >--------------------------------------------------------------------

 Module entry point from another module.

 ]]

 localfunction_xlit(args)
 localtitle_table=lang_data.translit_title_table;-- table of transliteration standards and the language codes and scripts that apply to those standards
 locallanguage_name;-- language name that matches language code; used for tool tip
 localtranslit;-- transliterated text to display
 localscript;-- IANA script
 localmsg;-- for when called functions return an error message
 localtemplate=args.templateorcfg.templates_t.transliteration;

 maint_cats={};-- initialize because when this module required into another module, these only declared once so only initialzed once
 maint_msgs={};

 ifis_set(args[3])then-- [3] set when {{transliteration|code|standard|text}}
 args.text=args[3];-- get the transliterated text
 args.translit_std=args[2]andargs[2]:lower();-- get the standard; lower case for table indexing

 ifnottitle_table[args.translit_std]then
 returnmake_error_msg(substitute(cfg.transl_t.unrecog_xlit_std,{args.translit_std}),args,template);
 end
 else
 ifis_set(args[2])then-- [2] set when {{transliteration|code|text}}
 args.text=args[2];-- get the transliterated text
 else
 ifargs[1]and(args[1]:match('^%a%a%a?%a?$')or-- args[2] missing; is args[1] a language or script tag or is it the transliterated text?
 args[1]:match('^%a%a%a?%-x%-'))then-- or is args[1] a private-use tag
 returnmake_error_msg(cfg.transl_t.no_text,args,template);-- args[1] is a code so we're missing text
 else
 args.text=args[1];-- args[1] is not a code so we're missing that; assign args.text for error message
 returnmake_error_msg(cfg.transl_t.missing_lang_scr,args,template);
 end
 end
 end

 ifis_set(args[1])then-- IANA language code used for HTML lang= attribute; or ISO 15924 script code
 ifargs[1]:match('^%a%a%a?%a?$')orargs[1]:match('^%a%a%a?%-x%-')then-- args[1] has correct form?
 args.code=args[1]:lower();-- use the language/script code; only (2, 3, or 4 alpha characters) or private-use; lower case because table indexes are lower case
 else
 returnmake_error_msg(substitute(cfg.transl_t.unrecog_lang_scr,{args[1]}),args,template);-- invalid language / script code
 end
 else
 returnmake_error_msg(cfg.transl_t.missing_lang_scr,args,template);-- missing language / script code so quit
 end

 localis_latn_text,pos,char;
 is_latn_text,args.text,pos,char=is_latin(args.text,args.code);-- is latn text? strip accept-as-written markup
 ifnotis_latn_textthen-- when text is not latn
 returnmake_error_msg(substitute(cfg.lang_xx_t.translit_nonlatn,{pos,char}),args,template);-- abandon with error message
 end


 args.italic,msg=validate_italic(args);
 ifmsgthen
 returnmake_error_msg(msg,args,template);
 end

 if'italic'==args.italicthen-- 'italic' when |italic=yes; because that is same as absent or not set and |italic=default
 args.italic=nil;-- set to nil; 
 end

 args.engvar=cfg.engvar_sel_t[args.engvar]orcfg.default_engvar;-- |engvar= when valid; cfg.default_engvar else

 ifoverride_table[args.code]then-- is code a language code defined in the override table?
 language_name=override_table[args.code];
 args.code=args.code:match('^%a%a%a?');-- if private use, strip all but language subtag
 elseiflang_table[args.code]then-- is code a language code defined in the standard language code tables?
 language_name=lang_table[args.code];
 elseiflang_dep_table[args.code]then-- is code a language code defined in the deprecated language code tables?
 language_name=lang_dep_table[args.code];
 elseifscript_table[args.code]then-- if here, code is not a language code; is it a script code?
 language_name=script_table[args.code];
 script=args.code;-- code was an ISO 15924 script so use that instead
 args.code='';-- unset because not a language code
 else
 returnmake_error_msg(substitute(cfg.transl_t.unrecog_lang_scr,{args.code}),args,template);-- invalid language / script code
 end
 -- here only when all parameters passed to make_translit() are valid
 returnmake_translit(args.code,language_name,args.text,args.translit_std,script,args.italic,args.engvar);
 end


 --[[--------------------------< X L I T >----------------------------------------------------------------------

 Module entry point from an {{#invoke:}}.

 ]]

 localfunctionxlit(frame)
 return_xlit(getArgs(frame));
 end


 --[[--------------------------< C A T E G O R Y _ F R O M _ T A G >--------------------------------------------

 Returns category name associated with IETF language tag if valid; error message else.

 All code combinations supported by {{lang}} and the {{lang-??}} templates are supported by this function.

 Module entry point from another module.

 ]]

 localfunction_category_from_tag(args_t)
 localsubtags={};-- IETF subtags script, region, variant, and private
 localraw_code=args_t[1];-- save a copy of the input IETF subtag
 locallink=cfg.keywords_t.affirmative==args_t.link;-- make a boolean
 locallabel=args_t.label;
 localcode;-- the language code
 localmsg;-- gets an error message if IETF language tag is malformed or invalid
 localcategory_name='';

 code,subtags.script,subtags.region,subtags.variant,subtags.private,msg=get_ietf_parts(raw_code);
 ifmsgthen
 localtemplate=(args_t.templateandtable.concat({'{{',args_t.template,'}}: '}))or'';-- make template name (if provided by the template)
 returnmake_error_span(template,msg);
 end

 raw_code=format_ietf_tag(code,subtags.script,subtags.region,subtags.variant,subtags.private);-- format to recommended subtag styles; private omitted because private
 category_name=language_name_get(raw_code,code);-- get language name; try IETF tag first, then code w/o variant then code w/ variant
 category_name=make_category(code,category_name,nil,true):gsub('[%[%]]','');

 iflinkthen
 returntable.concat({'[[:',category_name,']]'});
 else
 returncategory_name;
 end
 end


 --[[--------------------------< C A T E G O R Y _ F R O M _ T A G >--------------------------------------------

 Module entry point from an {{#invoke:}}.

 ]]

 localfunctioncategory_from_tag(frame)-- entry point from an {{#invoke:lang|category_from_tag|<IETF tag>|template=<template name>}}
 return_category_from_tag(getArgs(frame));-- pass-on the args table, nothing else; getArgs() so we also get parent frame
 end


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

 return{
 category_from_tag=category_from_tag,-- frame entry points when this module is #invoke:ed into templates/wikitext
 lang=lang,-- entry point for {{lang}}
 langx=langx,-- entry point for {{langx}}
 lang_xx_inherit=lang_xx_inherit,-- entry points for {{lang-??}}
 lang_xx_italic=lang_xx_italic,
 is_ietf_tag=is_ietf_tag,
 is_ietf_tag_frame=is_ietf_tag_frame,
 is_lang_name=is_lang_name,
 tag_from_name=tag_from_name,-- returns IETF tag associated with language name
 name_from_tag=name_from_tag,-- used for template documentation; possible use in ISO 639 name from code templates
 xlit=xlit,-- entry point for {{transliteration}}

 _category_from_tag=_category_from_tag,-- API entry points when this module is require()d into other modules
 _lang=_lang,
 _langx=_langx,
 _lang_xx_inherit=_lang_xx_inherit,
 _lang_xx_italic=_lang_xx_italic,
 _is_ietf_tag=_is_ietf_tag,
 get_ietf_parts=get_ietf_parts,
 _tag_from_name=_tag_from_name,
 _name_from_tag=_name_from_tag,
 _xlit=_xlit,
 _translation_make=translation_make,
 };