Only arrays return the number of elements in scalar context, lists don't.

Some people say that lists don't exist in scalar context (and I disagree, but that's really a pointless discussion), but if we assume they do exist, then the default behaviour of a list is scalar context is to return its last element: 

print scalar(1, 2, 3);

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prrint the 3.

(Update) and the last element of an empty list is not defined, which is why you get the warning.

In reply to Re: Empty List miracle(1) by moritz
in thread Empty List miracle(1) by rovf

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