good chemistry is complicated, and a little bit messy -LW |
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Calling defined for a hash key doesn't create anything.
There is a subtle difference internally between exists and defined. With exists, all Perl has to do is see if there's an entry in the hash table for that item. With defined, that value has to be inspected:
Using code like this: Granted, that's a million iterations, and the difference is only a couple of seconds. Hardly worth arguing over, but it's just a difference in the way of thinking about hashes.. In my head, what I'm looking for is the presence of a certain key in the hash (exists), not whether or not the value for that key in the hash is defined. You're right that functionally they're equivalent in this case. In reply to RE: RE: RE: A discriminating sort (and some damned lies)
by Fastolfe
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