I don't want hash to be modified when I just look for values in it. Another reason is I want to have warnings when I try to write on deep levels on such hashes, because this means error quite often.

:) You don't need autovivification.pm module for that, see Data::Diver

In reply to Re^4: No autovivification, for loop aliasing, lvalue vs rvalue in for loops by Anonymous Monk
in thread No autovivification, for loop aliasing, lvalue vs rvalue in for loops by leszekdubiel

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