Try just greping: 

my $non_empty = grep { $a{$_} ne "" } keys %a;
print "Keys with non-empty values: $non_empty\n";

__END__
Keys with non-empty values: 2

[download]

You then need to decide whether undef of 0 entries are empty or not.

In reply to Re: Count non-empty hash values by fishbot_v2
in thread Count non-empty hash values by pboin

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