|traduire_nom_langue is applied to the #LANG tag and returns a translation of the language code provided by that tag (fr, en, it, etc.) into that language.
An example of use:
<B_actus>
<ul>
<BOUCLE_actus(ARTICLES){!par date}{0,5}>
<li><a href="#URL_ARTICLE">#TITRE [- (#LANG|traduire_nom_langue)]</a></li>
</BOUCLE_actus>
</ul>
</B_actus>
Remarks: The translation of codes are made into the language that that code represents, and will follow the writing conventions of that language.
As such, "fr" will be translated as "français" with a lowercase "f", where as "es" will be translated as "Español" with an uppercase "E".