I know the following is heinous, & I also fussed with a number of solutions posed in earlier threads about similar questions. Unfortunately, none have worked thus far.

I'm wanting to define a regular expression which will be assigned to a constant, & obviously, I want to determine whether various strings match.

Assigning a pattern to a scalar value works: 

#!/usr/bin/perl

use strict;
use Data::Dumper;

my $regex = qr/^(\d{4})-(\d{2})-(\d{2})/;

my $s = '2011-02-15';
my ($y, $m, $d) = ($s =~ /$regex/)[0, 1, 2];
print Data::Dumper->Dump([$y, $m, $d], [qw/y m d/]);

[download]

However, I'm getting spanked when redefining the pattern as a constant/subroutine (Syntax obviously wrong...): 

#!/usr/bin/perl

use strict;
use Data::Dumper;
use constant REGEX => qr/^(\d{4})-(\d{2})-(\d{2})/;

my $s = '2011-02-15';
my ($y, $m, $d) = ($s =~ /&{[REGEX]}/)[0, 1, 2];
print Data::Dumper->Dump([$y, $m, $d], [qw/y m d/]);

[download]

Any help you can share would be greatly appreciated. I'm using Perl 5.8.8.

In reply to qr expression defined as constant? by Anonymous Monk

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