<ShamelessSelfPromotion>
You could also use the Filter::Interpolate module I put into Code Catacombs:

use Filter::Interpolate;
use constant TEST => 3;
my $string="123456";
$string =~ s/\Q$(TEST)\E/9/;
print $string, "\n";

$string =~ s/2/$(TEST)/;
print $string, "\n";
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</ShamelessSelfPromotion>

It should also be pointed out that the @{[THING]} hack will work with subroutines too. It will also work in double-quoted strings and anywhere else interpolation happens.

=cut
--Brent Dax

@HPAJ=split("", "rekcaH lreP rentonA tsuJ");
print reverse @HPAJ;  #sucky but who cares?
[download]