This is a bit confusingly written.

The question was about checking if a hash is empty, and %h in scalar context can be used to do this portably (though the relative recent change makes it more efficient).

That said,

%h in scalar context can't be used to get the number of keys portably.

keys(%h) in scalar context can be used to get the number of keys portably and efficiently.

That's not true. You could aways use There was a relatively recent change thatefficiency of hash in boolean context

Seeking work! You can reach me at ikegami@adaelis.com

In reply to Re^2: How to test for empty hash? by ikegami
in thread How to test for empty hash? by scareduck

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