The fragment you have shown will not compile. The following will compile:

(keys %$hash_ref)[-1]

... and will return the "last" key of hash %$hash_ref. But that would seem somewhat meaningless, as the keys of a hash do not have any specific order. Any apparent order of the keys may change when the elements of the hash are changed, or a different Perl is used.

In reply to Re: what is keys %$hash_ref [-1] by philipbailey
in thread what is keys %$hash_ref [-1] by Anonymous Monk

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