Provides everything that is missing in Regexp engine.
I've used Parse::RecDescent and Parse::Eyapp before,
but Regexp::Grammars is the new ultimate grammar king in Perl 5!
What I love in this module:
- syntax is similar to Perl 6
- hash match prevents grammar changes on new keys
- "require:" makes numeric range check easy
- context string available for fast debug
- "debug:" pragmas for advanced debugging
- easy aliasing of matched tokens
- balanced delimiters
- easy noncapture (amnesiac) syntax
- passing params to tokens
and many many more
Also there is "demo" section in package with nice examples that helped me may times to understand how to use features from this module.