That sounds like you're coming from PHP. Well, OK, I'll write a little utility function empty which should look a bit familiar. That way you can compare if 2 values are both empty. 
sub empty {
    my $r = shift;
    if(!ref $r) { return !$r }
    if(ref $r eq 'HASH') { return !keys %$r }
    if(ref $r eq 'ARRAY') { return !@$r }
    if(ref $r eq 'SCALAR') { return !$$r }
    return !1;    
}
$a = ''; $b = {}; $c = [];
if(empty($a) && empty($b) && empty($c)) { print "PASS"; }

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In reply to Re: How to compare an empty key with another empty key in associative array by bart
in thread How to compare an empty key with another empty key in associative array by nandymamith

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