Found another related discussion, curiously from the same OP.

No autovivification, for loop aliasing, lvalue vs rvalue in for loops

The related bug report argues, that aliases must trigger autovivification beforehand, in case an lvalue happens after.

https://github.com/Perl/perl5/issues/15583

I find this explanation unsatisfactory because I showed here that the aliasing of sub arguments don't trigger autovivification.

Hmm???

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

In reply to Re^3: unexpected modify hash in a distance with grep { $_ } by LanX
in thread unexpected modify hash in a distance with grep { $_ } by leszekdubiel

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