Hi monks, I have a hash of elements where each element can be either an undef or a value: 
$hash->{'a'} = undef;
$hash->{'b'} = 4.5;
$hash->{'c'} = 6;
$hash->{'d'} = undef;
...

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Is there a quick, perlish way to perform either of these 2 operations: 
1) check if the hash is empty (all elements are undef)
2) reset all elements to undef

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I know the obvious ways to do these, I'm kinda looking for a creative one-liner for each operation. thanks, Michael
edited by boo_radley for title : was "hash problem"

In reply to One liner to Check and undef hash elements by Anonymous Monk

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