I think that you should look for some module that does XSL or XSLT. Those should come with some filters to easy select what you want to exclude from the parsing. Besides, everything now is passing through some sort of XSL filter.

Yes, I know that it is XML but XSL's main function is precisely filtering XML elements.

I found this...

''Internally, XML::Schematron::LibXSLT uses the Gnome Project's XSLT proccessor via XML::LibXSLT and, while this proccessor is not 100% compliant with the XSLT spec at the time of this writing, it is the best XSLT libraray available to the Perl World at the moment. It is therefore possible that you might use a completely valid XSLT expression within one of your schema's tests that will cause this module to die unexpectedly.

For those platforms on which libxslt is not available, please see the documentation for XML::Scmeatron::Sablotron and XML::Schematron::XPath (also in this distribution) for alternatives. ''(here)