There are modules to do that, for example Data::Diver, or modules that disable autovivification.

There was also a proposal (and patch) that adds an "exists-or" operator \\ to perl, to parallel the "or" || and "defined-or" // operator. I don't know if it got accepted in the end.

Perl 6 - second systems done right

In reply to Re: recursive exists in perl by moritz
in thread recursive exists in perl by Anonymous Monk

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