You actual intent is a little unclear to me. Are you generating permutations with n terms of the list of items in @chartab followed by a comma? If so, recursion would seem the reasonable way to go. Something like (untested): 

use strict;
use warnings;

my @chartab = (0..9, 'a'..'z');
my $depth = 4;
print permute(\@chartab,'',$depth);

sub permute {
    my ($chartab_ref, $intro, $depth) = @_;
    return "$intro," if ($depth == 0);

    my $string = q{};
    foreach my $letter (@$chartab_ref) {
        $string .= permute($chartab_ref, $intro.$letter,$depth-1);
    }
    return $string;
}

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In reply to Re: loop in loop method evasion by Anonymous Monk
in thread loop in loop method evasion by motzi

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