The comma operator has a higher precedence than the not operator. The list of two expressions (the hash element and the array) has to be evaluated before not can be evaluated; that's the source of the void context warning.

I almost always use map with a block so I never have to think about this sort of thing.

Improve your skills with Modern Perl: the free book.

In reply to Re: Logical Not and arguments to grep by chromatic
in thread Logical Not and arguments to grep by tangent

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