> and why square brackets make so much difference to autovivification?

this

  
for my $e (@{[ $$n{'y'} ]}) { 
}

[download]

has no possible autovivification. It copies the list within [] and translates to 

  
for my $e (@{[ undef ]}) { 
}

[download]

Nota Bene: there is a fundamental difference between \@a and [@a] !

While both are array refs, only the first one keeps a link to @a while the latter is only an anonymous copy.

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to Re: No autovivification, for loop aliasing, lvalue vs rvalue in for loops by LanX
in thread No autovivification, for loop aliasing, lvalue vs rvalue in for loops by leszekdubiel

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