You're being bitten by "autovivification". When you check to see if $hash{d}{value} exists, Perl will autovivify $hash{d} if it doesn't already exist.

Your best solution is to do if ($hash{d} and !$hash{d}{value}) { ... }.

Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re: Heisenberg Uncertainty Hash by japhy
in thread Heisenberg Uncertainty Hash by Sprad

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