Preferably with  if (!keys %hash) { print "Empty" }.

This has the drawback of actually going through fetching all the keys for a tied hash, but the alternative (if (!%hash) { print "Empty" }) doesn't work at all for tied hashes.

If tied hashes aren't a concern, either way will do, but there is a difference to be aware of: the keys version will reset the hash's iterator (see each) while the other way will leave it unchanged.

In reply to Re: How do I find out if a hash is empty? by ysth
in thread How do I find out if a hash is empty? by Pug

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