There's a nice example in Algorithm::Loops that may apply, here's a possible usage:

#!/usr/bin/perl
use strict;
use warnings;
use Algorithm::Loops qw( NestedLoops );

my @list = NestedLoops(
   [ ( [ 'A' .. 'F' ] ) x 4 ],
   sub { return join '', @_ },
);
print "$_\n" foreach @list;
[download]

The funny side is that I don't quite understand this code ;)