G'day Rajini,
I am looking for must_match perl module in opensource. could you please point me to this module.
I'm afraid I have no idea what the "must_match" Perl module would do. The usual way you'd find open source Perl modules is to visit http://search.cpan.org/ and then put the module name (or even part of a name) into the search box and see what you get.
When I searched for "must_match", I found the documetation for App::ZofCMS::PluginReference (http://search.cpan.org/perldoc?App::ZofCMS::PluginReference) because there is a method called must_match documented on that page, but I'm not certain that that is what you're looking for.
The purpose of this mailing list isn't to provide assistance to Perl students, but rather so that Perl trainers can share ideas about their training courses. I don't think the others on this list will mind a lot if you take a bit of time to think carefully about what your question is; and ask it again. Preferably you'd include what you think the module is called, what you think it does (giving about a paragraph of detail), perhaps how/when you came across it in the past, where you've looked etc.
You may also find the perlmonks web forum (http://perlmonks.org/) to be a helpful place to seek further assistance.
All the best, Jacinta