diff_pp (ParseTreeGauntlet)

    # File lib/gauntlet_parsetree.rb, line 35
      def diff_pp o1, o2
        require 'pp'

        File.open("/tmp/a.#{$$}", "w") do |f|
          PP.pp o1, f
        end

        File.open("/tmp/b.#{$$}", "w") do |f|
          PP.pp o2, f
        end

        `diff -u /tmp/a.#{$$} /tmp/b.#{$$}`
      ensure
        File.unlink "/tmp/a.#{$$}" rescue nil
        File.unlink "/tmp/b.#{$$}" rescue nil
      end