Ruby Parser

Hi !

A few month ago, for the ruby quiz 61, Dennis Ranke proposed a solution
involving a pure-ruby parser
(http://www.ruby-talk.org/cgi-bin/scat.rb/ruby/ruby-talk/174842).

I’m wondering if any project already tool this parser to do something
more finalized with it ? Or is there any other pure ruby parser that
does not require external tools ?

Pierre