Here a concise way for cleaning up afterwards:

 $h{$_} // delete $h{$_} for keys %h

Unfortunately the even shorter approach doesn't work with deleting aliases

$_ // delete $_ for values %h

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re^2: Consise way to filter out keys with undef values from a hash slice? by LanX
in thread Consise way to filter out keys with undef values from a hash slice? by nysus

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