What about something like this 
#assume that %hash is already initialized
%hash = (%hash, reverse %hash);

[download]
Of course, you are still storing everything twice, but in order to be able to lookup on either value, you'll need something like this.

thor

Feel the white light, the light within
Be your own disciple, fan the sparks of will
For all of us waiting, your kingdom will come

In reply to Re: Bi-Directional Hash Lookup by thor
in thread Bi-Directional Hash Lookup by PerlingTheUK

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