wa2nlinux:

You don't need to. I used qw just for making the example. Perhaps I should've written it like this:

#!/usr/bin/perl
use strict;
use warnings;

my $r = "ab+c*d";
my $rRegex = qr/$r/;
while (my $t = <DATA>) {
    if ($t =~ $rRegex) {
        print "MATCH: $t\n";
    }
}
__DATA__
abcd
aabbbd
acccd
dbca
[download]

...roboticus

When your only tool is a hammer, all problems look like your thumb.