No, $hr->{stuff} alone doesn't autovivify the element. It's the dereferencing operation 

     $hr->{stuff}->{foo}
                 ^^

[download]

that autovivifies, not merely accessing the hash element.

As for side effects with tied hashes, I mean that arbitrary code could be associated with the tied read operation.

In reply to Re^4: Possible useless use of map by almut
in thread Possible useless use of map by andreas1234567

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