I'd do it with 1 as the hash values, because then you can simply write if ($hash{$key}), and hell doesn't break loose if you happen to forget the exists in front of it. And speaking from my own experience, at one point you will forget it.

In reply to Re: Effeciency of key-only hash by moritz
in thread Effecicncy of key-only hash by brycen

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