Seattle.rb

Name: ruby_parser

Project URL: https://github.com/seattlerb/ruby_parser

Rubygems URL: ruby_parser

Seattle.rb Contributors: 1

Description:

ruby_parser (RP) is a ruby parser written in pure ruby (utilizing racc–which does by default use a C extension). It outputs s-expressions which can be manipulated and converted back to ruby via the ruby2ruby gem.

As an example:

def conditional1 arg1
  return 1 if arg1 == 0
  return 0
end

becomes:

s(:defn, :conditional1, s(:args, :arg1),
  s(:if,
    s(:call, s(:lvar, :arg1), :==, s(:lit, 0)),
    s(:return, s(:lit, 1)),
    nil),
  s(:return, s(:lit, 0)))

Tested against 801,039 files from the latest of all rubygems (as of 2013-05):

1.8 parser is at 99.9739% accuracy, 3.651 sigma
1.9 parser is at 99.9940% accuracy, 4.013 sigma
2.0 parser is at 99.9939% accuracy, 4.008 sigma
2.6 parser is at 99.9972% accuracy, 4.191 sigma
3.0 parser has a 100% parse rate.
- Tested against 2,672,412 unique ruby files across 167k gems.
- As do all the others now, basically.

Last Update: 2026-03-17 00:46:20 UTC

Contributors:

Ryan Davis