Actually, I do use CGI::Application. And I have used hashes as dispatch tables before (actually reinvented that wheel myself after dipping my toe in some assembly code). I usually use switch type statements for combining regex tests and other kinds of comparisons/tests (like in the example). I was not aware of Tie::Hash::Regex however. That is something I will rtfm on. CPAN is so massive I find it hard to keep up with it all (and that is a good thing).

UPDATE:Tie::RegexpHash also seems like a pertinent module to check out. It allows one to use regexes as hash keys.