We don't have to quibble over semantics, do we?? To me a list is undefined even if it exists but has no items to encompass aor if it has no explicitly named members; to you the very same list is defined to be empty. In any case, I did regard a list devoid of members as being "empty" in my post.

Perl is not matlab or mathematica nor would i wish it to be, even if i were a mathematician I'd appreciate the difference between the return values being 0 or undef, because logically the difference tells me something about the state of operations within the returning subroutine.

Regardless, the sum 0, @list fix is completely fine.

I don't disagree with you or BrowserUk, it's a perfect solution to OP's problem. I just don't see (0, ()) as being the same argument list as (), neither does List::Util::sum() - one is clearly defined, another is not (or in your speak, one is empty, another is not).

perl -e '$,=$",$_=(split/\W/,$^X)[y[eval]]]+--$_],print+just,another,split,hack'er

In reply to Re^3: List::Util::sum() and empty lists... by Firefly258
in thread List::Util::sum() and empty lists... by blazar

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