Hi crenz, thanks for you reply. #2 works very nicely, but I can't make #1 work. Your code prints "empty" for both of these hashes.

$hash->{'a'} = 1;
$hash->{'b'} = undef;
$hash->{'c'} = undef;
$hash->{'d'} = undef;
if (scalar grep {defined} values %{$hash} == 0) {
   print "empty\n";
}

$hash->{'a'} = undef;
$hash->{'b'} = undef;
$hash->{'c'} = undef;
$hash->{'d'} = undef;
if (scalar grep {defined} values %{$hash} == 0) {
   print "empty\n";
}
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