Editing Template:Lang/doc (section)

== Parameters ==
{| class="wikitable"
|+ Lang supported parameters
! style="width: 15%;" | Parameter
! Definition
! style="width: 10%;" | Yields to
! style="width: 12%;" | Alias
|-
| {{para|code}} || [[IETF language tag]] for the content in <code>text</code> || – || {{para|1}}
|-
| {{para|text}}|| non-English text || – || {{para|2}}
|-
| {{para|rtl}} || <kbd>yes</kbd> indicates that the writing system used for the content in {{para|text}} is right-to-left; accepted values are: <kbd>no</kbd> (default), <kbd>yes</kbd> || IETF script subtag in {{para|code}} (if provided) ||
|-
| {{para|italic}} || {{crossreference|see table "lang {{pipe}}italic{{=}} parameter operation"}}; accepted values are: <kbd>yes</kbd>, <kbd>no</kbd>, <kbd>unset</kbd>, <kbd>invert</kbd>, <kbd>default</kbd> || – || {{para|italics}}, {{para|i}}
|-
| {{para|size}}|| specifies font size of the content in <code>text</code>; use a value suitable for use with the CSS <code>font-size</code> property; this should almost always be a relative value supplied in <kbd>{{mxt|%}}</kbd> or <kbd>{{mxt|em}}</kbd> units, not a fixed <kbd>{{!mxt|px}}</kbd> value. || – ||
|-
| {{para|proto}} || accepted values are: <kbd>no</kbd> (default) or <kbd>yes</kbd> (default for private-use language tags with the <kbd>-x-proto</kbd> subtags); when <kbd>yes</kbd> (default or explicit), prefixes rendered text with an asterisk indicating 'unattested' || – || 
|-
| {{para|cat}} || inhibits automatic categorization; mirror version of {{para|nocat}}; accepted values are: <kbd>no</kbd>, <kbd>n</kbd>, <kbd>false</kbd>, <kbd>f</kbd>, <kbd>off</kbd>, <kbd>0</kbd> || – ||
|-
| {{para|nocat}} || inhibits automatic categorization; mirror version of {{para|cat}}; accepted values are: <kbd>yes</kbd>, <kbd>y</kbd>, <kbd>true</kbd>, <kbd>t</kbd>, <kbd>on</kbd>, <kbd>1</kbd> || – ||
|-
|}

{| class="wikitable" id="italic parameter"
|+ Lang {{pipe}}italic= parameter operation
|-
! {{pipe}}italic= value !! description !! example code !! result !! html markup
|-
| rowspan="4" | {{Plainlist|
* parameter not present;
* parameter present, not set;
* invalid value
}}
| rowspan="7" | {{Plainlist|
* module applies style from:
* &nbsp;&nbsp;auto-italics or
* &nbsp;&nbsp;script subtag <code>latn</code>;
* else inherits from external markup;
* invalid values treated as default
}}
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru|тундра}}</syntaxhighlight>
| {{lang|ru|тундра}}
| {{code|{{lang|ru|тундра}}}}
|-
| <code>{{deprecated code|red=yes|<nowiki>{{lang|ru|tûndra}}</nowiki>}}</code>
| {{lang|ru|tûndra}}
| {{code|{{lang|ru|tûndra}}}}<br />Incorrect markup; this requires {{para||ru-Latn}}.
|-
| <syntaxhighlight lang="wikitext" inline="1">{{lang|fr|toundra}}</syntaxhighlight>
| {{lang|fr|toundra}}
| {{code|{{lang|fr|toundra}}}}
|-
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru-Latn|tûndra}}</syntaxhighlight>
| {{lang|ru-Latn|tûndra}}
| {{code|{{lang|ru-Latn|tûndra}}}}
|-
| rowspan="3" | <kbd>default</kbd>
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru|тундра|italic=default}}</syntaxhighlight>
| {{lang|ru|тундра|italic=default}}
| {{code|{{lang|ru|тундра|italic=default}}}}
|-
| <syntaxhighlight lang="wikitext" inline="1">{{lang|fr|toundra|italic=default}}</syntaxhighlight>
| {{lang|fr|toundra|italic=default}}
| {{code|{{lang|fr|toundra|italic=default}}}}
|-
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru-Latn|tûndra|italic=default}}</syntaxhighlight>
| {{lang|ru-Latn|tûndra|italic=default}}
| {{code|{{lang|ru-Latn|tûndra|italic=default}}}}
|-
| rowspan="4" | <kbd>no</kbd>
| rowspan="4" | {{Plainlist|
* module applies upright style;
* overrides auto-italics
* overrides script subtag <code>latn</code>;
* overrides external markup
}}
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru|тундра|italic=no}}</syntaxhighlight> || {{lang|ru|тундра|italic=no}} || {{code|{{lang|ru|тундра|italic=no}}}}
|-
| <syntaxhighlight lang="wikitext" inline="1">{{lang|fr|toundra|italic=no}}</syntaxhighlight> || {{lang|fr|toundra|italic=no}} || {{code|{{lang|fr|toundra|italic=no}}}}
|-
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru-Latn|tûndra|italic=no}}</syntaxhighlight> || {{lang|ru-Latn|tûndra|italic=no}} || {{code|{{lang|ru-Latn|tûndra|italic=no}}}}
|-
| <syntaxhighlight lang="wikitext" inline="1">''{{lang|fr|toundra|italic=no}}''</syntaxhighlight> || ''{{lang|fr|toundra|italic=no}}'' || {{code|''{{lang|fr|toundra|italic=no}}''}}
|-
| rowspan="2" | <kbd>yes</kbd>
| rowspan="2" | {{Plainlist|
* module applies italic style;
* ignores auto-italics;
* ignores script subtag <code>latn</code>
}}
| <code>{{deprecated code|red=yes|<nowiki>{{lang|ru|тундра|italic=yes}}</nowiki>}}</code>
| {{lang|ru|тундра|italic=yes}}
| {{code|{{lang|ru|тундра|italic=yes}}}} Incorrect markup per [[MOS:BADITALICS]].
|-
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru-Latn|tûndra|italic=yes}}</syntaxhighlight>
| {{lang|ru-Latn|tûndra|italic=yes}}
| {{code|{{lang|ru-Latn|tûndra|italic=yes}}}}
|-
| rowspan="4"| <kbd>unset</kbd>
| rowspan="4" | {{Plainlist|
* module applies no style;
* inherits style from external markup;
* disables auto-italics
* overrides script subtag <code>latn</code>;
}}
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru|тундра|italic=unset}}</syntaxhighlight>
| {{lang|ru|тундра|italic=unset}}
| {{code|{{lang|ru|тундра|italic=unset}}}}
|-
| <code>{{deprecated code|red=yes|<nowiki>''{{lang|ru|тундра|italic=unset}}''</nowiki>}}</code>
| ''{{lang|ru|тундра|italic=unset}}''
| {{code|''{{lang|ru|тундра|italic=unset}}''}} Incorrect markup per [[MOS:BADITALICS]].
|-
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru-Latn|tûndra|italic=unset}}</syntaxhighlight>
| {{lang|ru-Latn|tûndra|italic=unset}}
| {{code|{{lang|ru-Latn|tûndra|italic=unset}}}}
|-
| <syntaxhighlight lang="wikitext" inline="1">''{{lang|ru-Latn|tûndra|italic=unset}}''</syntaxhighlight>
| ''{{lang|ru-Latn|tûndra|italic=unset}}''
| {{code|''{{lang|ru-Latn|tûndra|italic=unset}}''}}
|-
| rowspan="4" | <kbd>invert</kbd>
| rowspan="4" | {{Plainlist|
* module applies no style;
* inverts style in internal markup;{{efn|name=invertunset}}
* disables auto-italics
* overrides script subtag <code>latn</code>;
}}
| <code>{{deprecated code|red=yes|<nowiki>{{lang|ru|тундра|italic=invert}}</nowiki>}}</code>
| {{lang|ru|тундра|italic=invert}}
| {{code|{{lang|ru|тундра|italic=invert}}}} Incorrect markup per [[MOS:BADITALICS]].
|-
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru|''тундра''|italic=invert}}</syntaxhighlight>
| {{lang|ru|''тундра''|italic=invert}}
| {{code|{{lang|ru|''тундра''|italic=invert}}}}
|-
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru-Latn|tûndra|italic=invert}}</syntaxhighlight>
| {{lang|ru-Latn|tûndra|italic=invert}}
| {{code|{{lang|ru-Latn|tûndra|italic=invert}}}}
|-
| <syntaxhighlight lang="wikitext" inline="1">{{lang|ru-Latn|''tûndra''|italic=invert}}</syntaxhighlight>
| {{lang|ru-Latn|''tûndra''|italic=invert}}
| {{code|{{lang|ru-Latn|''tûndra''|italic=invert}}}}
|-
|}

===Notes===
{{Notelist|refs=
{{efn|name=invertunset|compare {{para|italic|invert}} to {{para|italic|unset}}:
:<syntaxhighlight lang="wikitext" inline="1">{{Lang|de|... ein neues Opernprojekt in Angriff: ''Das Käthchen von Heilbronn'', nach Heinrich von Kleists gleichnamigem Drama.|italic=invert}}</syntaxhighlight>
::{{Lang|de|... ein neues Opernprojekt in Angriff: ''Das Käthchen von Heilbronn'', nach Heinrich von Kleists gleichnamigem Drama.|italic=invert}}
:<syntaxhighlight lang="wikitext" inline="1">{{Lang|de|''... ein neues Opernprojekt in Angriff: ''Das Käthchen von Heilbronn'', nach Heinrich von Kleists gleichnamigem Drama.''|italic=unset}}</syntaxhighlight>
::{{Lang|de|''... ein neues Opernprojekt in Angriff: ''Das Käthchen von Heilbronn'', nach Heinrich von Kleists gleichnamigem Drama.''|italic=unset}}
}}
}}

===The function selector parameter===
{{tlx|lang}} uses the Lua function <code>lang()</code> [[Module:Lang]]. That module also supports all of the {{tnull|lang-??}} templates using the Lua functions <code>lang_xx_inherit()</code> and <code>lang_xx_italic()</code>. The module has other functions that may be useful. The function selector parameter {{para|fn}} tells module:lang which function to execute. The available functions are:
*<code>is_ietf_tag</code> – returns <code>true</code> if the provided [[IETF language tag]] is valid; nil else
**<code><nowiki>{{lang|fn=is_ietf_tag|nv}}</nowiki></code> →{{lang|fn=is_ietf_tag|nv}}←
**<code><nowiki>{{lang|fn=is_ietf_tag|xx}}</nowiki></code> →{{lang|fn=is_ietf_tag|xx}}←
*<code>is_lang_name</code> – returns <code>true</code> if the provided language name is valid; nil else
**<code><nowiki>{{lang|fn=is_lang_name|navajo}}</nowiki></code> →{{lang|fn=is_lang_name|navajo}}←
**<code><nowiki>{{lang|fn=is_lang_name|xxxxx}}</nowiki></code> →{{lang|fn=is_lang_name|xxxxx}}←
*<code>lang</code> – the function that renders {{tlx|lang}}; listed here for completeness, this particular usage is more-or-less pointless
*<code>name_from_tag</code> – returns the language name associated with the provided IETF language tag:
**<code><nowiki>{{lang|fn=name_from_tag|apa}}</nowiki></code> → {{lang|fn=name_from_tag|apa}}
*<code>tag_from_name</code> – returns the ISO 639 language code (sometimes IETF language tag) associated with the provided language name:
**<code><nowiki>{{lang|fn=tag_from_name|havasupai}}</nowiki></code> → {{lang|fn=tag_from_name|havasupai}}
*<code>xlit</code> – the function that renders {{tlx|transliteration}}; listed here for completeness, this particular usage is more-or-less pointless
**<code><nowiki>{{lang|fn=xlit|ar|DIN|al-Ḫawārizmī}}</nowiki></code> → {{lang|fn=xlit|ar|DIN|al-Ḫawārizmī}}