tilly is right, and if you want to know why you might like to read Perl Guts Illustrated which is really quite interesting.

It also makes sense that exists is faster than checking the truth of the value, but you will then need to be careful about auto-vivification. Also if you plan on doing a lot of removing from the set you may want to compare the performance of undef-ing a hash entry versus delete-ing it.

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

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