See perldata, first paragraph:

Hashes are unordered collections of scalar values indexed by their associated string key.

So, you can't use any scalar as a hash key, just a string.

There is the module Tie::RefHash though, which allows you to use references as hash keys, which seems to be what you're trying to do.

In reply to Re: Problem to store referrence as key value in a hash by Corion
in thread Problem to store referrence as key value in a hash by Anonymous Monk

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