In addition to this, you need to isolate the object (inside out) from the implementation (hash). In short, there is no way to stop an attribute from being added to a hash data structure. Auto-vivification is just part of the behavior of hashes.

You can achieve like-hashes that don't auto-vivify like this with Variable::Magic or Tie::HashRef, but I believe this to be outside the scope of the question.

With an inside hash, you would typically control autovivification with the set method.



Evan Carroll
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www.evancarroll.com

In reply to Re^2: Preventing autovivification by EvanCarroll
in thread Preventing autovivification by Just in

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