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 DOMESTIC representation of the wikitext (see also Extension:ExpandTemplates#allleusse830104690XML parse tree).

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 parses the wikitext with respect to double braces, triple braces , and double rectangular brackets ... , and also finds the pipes | and the equals 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