Note: Before I start, I have noticed your other suggestion, however this is based off of this code.

Well, I've modified your suggestion a little, and assuming I understood your suggestion's intent, I seem to have screwed it up somewhere along the line, because it still does not handle ( ) properly, but I can't see why. This is what I now have:

use Parse::RecDescent;
use Data::Dumper;
use strict;
use warnings;

$::RD_TRACE = 1;


my $grammar = q~

   expression: <leftop: term termop term> eod

   termop: /and/i | /xor/i | /or/i

   term: '(' <commit> expression ')' | condition

   condition: element comparison element

   element: '<' <commit> /-?\w+/ '>'
          | /\d+/

   comparison: /=[><]=/ <commit> <error: Unable to match comparison>
             | /=?[><]=?/
             | '='
             | '!='

   eod: /^\Z/

~;

my $parser = new Parse::RecDescent($grammar) or die;
#defined($parser->RecTest('h =>= h')) or die;

my $test = '(<MONTH> => <DAY>)'; # or (<MONTH> = <MARCH> and <DAY> = <
+TUESDAY>)';

print Dumper($parser->expression($test));

[download]

I repeatedly get "$VAR1 = undef;" in reply, as well as enough debugging info to scroll off my screen (unfortunately I can't capture it into a file either, Parse::RecDescent overrides any re-declarations on STDERR, and I can't use "perl language.pl | more" or any other similar methods since those don't want to capture the error messages...) Anyone see what I'm missing, it's probably obvious, but I've been staring at it for 4 hours now without anything more constructive happening than the condensing of a few rules in the grammar declaration.




My code doesn't have bugs, it just develops random features.

Flame ~ Lead Programmer: GMS (DOWN) | GMS (DOWN)

In reply to Re: &bull;Re: Parse::RecDescent and mini-language parsing by Flame
in thread Parse::RecDescent and mini-language parsing by Flame

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