If you have a function that always returns exactly one item (as the list of items that it returns), then it doesn't make sense to change this function to return a zero-item list in one special case.

That's not what return; does. It returns something that's false in boolean, scalar, and lists contexts. I know you know this; it just seems valuable to be very explicit about what we're discussing.

Now (on topic), it's difficult for Perl::Critic to recognize the semantic need for that with regard to any single specific Perl function. It seems like a variant of the semi-predicate problem; what does return undef; mean?

Damian's rule is Use a bare return to return failure. I believe that's good advice.

In reply to Re^7: Module Announcement: Perl-Critic-1.01 (scalar) by chromatic
in thread Module Announcement: Perl-Critic-1.01 by jthalhammer

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