Re^4: When DOESN'T "Use of uninitialized value" show up?

in reply to Re^3: When DOESN'T "Use of uninitialized value" show up?
in thread When DOESN'T "Use of uninitialized value" show up?

"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".

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Re^5: When DOESN'T "Use of uninitialized value" show up? by ikegami (Patriarch) on Dec 17, 2011 at 09:12 UTC
And that's the part where I disagree. If $a->{b} doesn't exist, we know that $a->{b}{c} cannot exist, But he isn't checking if `$a->{b}` exists, so it's possible that `$a->{b}{c}` can exist. Perl is being asked if `$a->{b}{c}` exists, and it's being done a few steps after autovivifying `$a->{b}`.	[reply] [d/l] [select]

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