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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