I see what you mean.  So, one could conclude that getting no warning in the OP's case (with map) is in fact the appropriate behavior (as the $hr->{$_} is not useless), while getting the warning with for seems more questionable  (in which case I wouldn't consider it a bug to silence a useless "Useless use of..." warning :)

In reply to Re^6: Possible useless use of map by almut
in thread Possible useless use of map by andreas1234567

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