I think you might mean the prevention of addition of keys to a hash, but if you really mean autovivification, there's

no autovivification qw( strict fetch exists delete store );

Update: Oops, I missed "I'm unable to use any modules that require installation". I'm not sure how we can help if you can't install our code.

In reply to Re: Preventing autovivification by ikegami
in thread Preventing autovivification by Just in

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