"b => {}" is required so that the presence of {c} can be checked.

And that's the part where I disagree. If $a->{b} doesn't exist, we know that $a->{b}{c} cannot exist, and perl could know too. The fact that such reads autovivify are really only due to a quirk in the implementation, and not deducible from a general rule like "autovivification happens only when it needs to".

Perl 6 - second systems done right

In reply to Re^4: When DOESN'T "Use of uninitialized value" show up? by moritz
in thread When DOESN'T "Use of uninitialized value" show up? by Tim McDaniel

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