Re: Regexp::Common inside Parse::RecDescent

You'll have to have the use inside the parser code, i.e. in the generated code. This means you should use a start-up action since the first thing to do when the parser starts is to load the module. Try this for the grammar:

my $g = q(

    { use Regexp::Common qw(URI); }

    CommentLine: '#' /.*/
    {{comment=>$item[2]}}

    UriLine: 'u=' /$RE{URI}{HTTP}/ {{uri => $item[2]}}

    Line: CommentLine  | UriLine
    {$item[1]}

  );
[download]

See Parse::RecDescent's POD under 'Start-up actions' for details.

IMHO, the grammar should definitely be in single quotes since it should not be interpolated in contrast with what Abigail-II says.

Hope this helps, -gjb-

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Re: Re: Regexp::Common inside Parse::RecDescent by demerphq (Chancellor) on Aug 21, 2003 at 17:49 UTC
IMHO, the grammar should definitely be in single quotes since it should not be interpolated in contrast with what Abigail-II says. You're both wrong. :-) No just kidding. You are both right. Abigails suggestion would work fine if the $RE expanded before P::RD ever saw it. OTOH, it makes more sense to me to use your approach of use()ing the module inside of the grammar. And personally I prefer single quoted here docs for my grammars because it avoids the double interpolation problem that can crop up unexpectedly if you arent careful. --- demerphq _{<Elian> And I do take a kind of perverse pleasure in having an OO assembly language...}	[reply] [d/l]
Re: Re: Re: Regexp::Common inside Parse::RecDescent by Anonymous Monk on Aug 23, 2003 at 17:46 UTC
I suggest using here-docs for grammars. #!perl use warnings; use strict; my $one = q{/\d \\ \/ \\/ / }; my $two = <<'--snip--'; /\d \\ \/ \\/ / --snip-- print "\$one is `$one'\n\$two is `$two'\n"; __END__ [download] This prints $one is `/\d \ \/ \/ / ' $two is `/\d \\ \/ \\/ / ' [download] which means you needn't escape your backslashes in single-quote here-docs. This can make regexes more readable.	[reply] [d/l] [select]