However, this claim would imply that stringification defines a bijection between objects and their hash keys.

Ergo, hash keys are all you need! ;-)

in theory yes, practically no.

There is no pure perl way to get the ref from the stringification, as long the relation is stored in a hash (sic).

And yes collisions can happen, when strings and references are mixed into one set...then resulting into the need of a specialized stringification.

Cheers Rolf

In reply to Re^8: Using hashes for set operations... by LanX
in thread Using hashes for set operations... by LanX

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