From: Lex Williams <etaern@...>
Date: 2008-08-30T03:48:40+09:00
Subject: Re: how can I debug treetop grammar?

Would you please walk me through a debugging example ? Considering this 
grammar :

grammar Dp
        rule all
        day space month {
                        def value
                                day.value.to_s + " " + month.value
                        end
                }
  end

  rule day
        [1-9] [1-9] / "" {
        def value
                                text_value.to_i
                        end
        }
   end

        rule space
                ' '*
        end

        rule month
                "Jan" / "Feb" / "Mar" / "Apr" / "May" / "Jun" / "Jul" / 
"Aug" / "Sep" / "Oct" / "Nov" / "Dec" / "" {
                        def value
                                text_value
                        end
                }
        end


end

and the following code :

equire "rubygems"
require "treetop"

Treetop.load "dp"

parser  = DpParser.new
node    = parser.parse("12")
another = parser.parse("Feb")
lastone = parser.parse("12 Feb")
puts node.value
puts another.value
puts lastone.value

-------------------------------------------------------------------------------
i'm getting back syntax nodes , but I can't call value on any of them . 
could you please show me how you would debug the rules ?
hope I'm not asking for too much !
Thanks ,
   Lex
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