Q: How to Replace content inside custom tag in MediaWiki before saving to database? First of all, I have both MW 1.16 and 1.17 set up with PHP 5.3.5, MySQL 5.5.8 and Apache 2.2.17.
I've wrote a simple $wgExtensionFunction which right now does nothing. 
$wgExtensionFunctions[] = "wfTestExtension";

function wfTestExtension() { global $wgParser;
$wgParser->setHook("myTag", "renderTest");
}

function renderTest($input) {
   return $input;
}

What I want to do is, if I type <myTag>Blah blah blah</myTag> in the add or edit form, I want to be able to change the contents inside myTag BEFORE saving it to the database. What mechanism should I use for this? I'm assuming hooks?  For example, with the ArticleSave hook, the $text var already has the  <myTag> stripped out, so there's no way of trying to parse the string and figuring out what it is that was originally inside the <myTag>
I've spent hours trying to find something on Google, but I've almost given up. Any advice at all would be highly appreciated.
Cheers. 

A: Maybe http://www.mediawiki.org/wiki/Manual:Hooks/ParserBeforeStrip would work:
"Used to process the raw wiki code before any internal processing is applied"

A: This is another "maybe" but you could try using a combination of a template and the {{subst:}} command (see transclusion).
(See also Wikis and Wikipedia)
