I needed to reformat a bunch of Perl code, so I began writing this as an exercise to try and learn regular expressions better, but I've gotten stuck and I'm not sure why.

It's a very light weight perl parser that handles just a subset of perl.

Here's the code:

#!/usr/bin/perl -w

use strict;

my $bareword  = qr/(\w+)/;
my $quotelike = qr/((['"]).+?\2)/;
my $subscript = qr/([\[{]\w+[\]\}])/;
my $variable  = qr/(\$\w+($subscript)*)/;
my $sub_arg  = qr/($quotelike|$variable|$bareword)/;
my $sub_args  = qr/($sub_arg,)*($sub_arg)/;
my $subroutine = qr/((\w+::)*\w+\($sub_args)/;

while (<>) {
    my @args = ();
    my @labels = ();
    my ($spacer, $obj, $method) = m/^(\s+)(\$\w+->)(\w+)\(/gc;
    LOOP: {
        push(@args, $1),    redo LOOP if m/\G$quotelike,?\s*/gc;
        push(@args, $1),    redo LOOP if m/\G$variable,?\s*/gc;
        push(@args, $1),    redo LOOP if m/\G$subroutine,?\s*/gc;
        push(@args, $1),    redo LOOP if m/\G$bareword,?\s*/gc;
    }
    @labels = ($method eq "hidden") ? qw(name value) : 
                      ##integer, text
                                      qw(name label value maxlength ex
+tras subtext size uiLevel defaultValue hoverHelp)
    ;
    print join '', $spacer, $obj, $method, "(\n";
    for(my $index=0; $index < @args; ++$index) {
        print join '', "\t\t-", $labels[$index], ' => ', $args[$index]
+, ",\n";
    }
    print join '', $spacer, ");\n";

}

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This is the line I'm trying to parse:

    $f->readOnly($session{form}{cid},WebGUI::International::get(469,"W
+ebGUIProfile"));

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And this is the formatted output, incorrect:

                $f->readOnly(
                -name => $session{form}{cid},
        -label => WebGUI::International::get(469,
                -value => "WebGUIProfile",
                );

[download]

The $sub_args regex is only matching the second set of parentheses, and I have no idea why. Can anyone clue me in?

In reply to Nesting regexen by colink

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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