Well, in general you're doing pretty well, I think. You're using hashes for uniqueness lookups, which is always a good first step. :)

One thing that came to my mind is why don't you combine the two steps? So you'd end up w/ something like this: 

    my($self) = @_;

    my(%seen, %r);
    my @common = qw(a and at);
    @seen{@common} = ();
    for my $r (@words) {
        next if exists $seen{ lc $r };
        $r{lc $r} = 1;
    }
    my @words = sort keys %r;

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In reply to Re: List processing performance by btrott
in thread List processing performance by Odud

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