Manual:Preprocessor DOM.php

Description
This file contains functions for recursively expanding variables, parser functions, templates, and template parameters. As an intermediate step it creates an XML DOM representation of the wikitext (see also Extension:ExpandTemplates).

Functions called from Parser.php include:
 * function preprocessToObj, which preprocesses wikitext and returns a document tree, also called DOM tree. It calls:
 * function preprocessToXml, which parser the wikitext with respect to double braces, triple braces , and double rectangular brackets ... , and also finding the pipes | and the equal signs =. The result is the DOM tree.
 * function expand, which produces the expanded wikitext from the DOM tree. It performs double-brace expansion, calling function braceSubstitution in Parser.php, and triple-brace expansion, calling function argSubstitution in Parser.php.

External link

 * The MediaWiki parser, uncovered