Thanks! :)

> Lastly, I have decided to have all the result hashes "look the same" in that every element value is undef--which may or may not be more efficient!

unfortunately this collides with my requirement to support all kind of sets:

From the OP

This is fundamentally wrong because keys are stringifications and any reference type will not be reproduced (just think about arrays of objects or a AoH or ...)

Cheers Rolf

In reply to Re^6: Using hashes for set operations... by LanX
in thread Using hashes for set operations... by LanX

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