It seems to me that you do know the answer to your question. It may be that defined is fine for you. I'd say that exists is the way to go though. I wouldn't be concerned about efficiency for such an atomic statement. Do you have any particular situation in which this may matter?!?

In reply to Re: What is the best way to find the key is exists or not in a hash ? by blazar
in thread What is the best way to find the key is exists or not in a hash ? by swaroop

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