Autovivification does not occur here; it only happens when the non-existent thing in question is an lvalue: 
%hash = qw( a 1 b 2 c 3 );
@array = (1,2,4,8);

$x = $hash{z};    # no auto-viv
$x = $array[10];  # no auto-viv

1 for $hash{y};   # auto-viv
1 for $array[7];  # auto-viv

[download]
Bonus: why are those bottom two treating the value in question as an lvalue?

_____________________________________________________
Jeff japhy Pinyan: Perl, regex, and perl hacker.
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

In reply to Re: Re: Mapping array over a hash by japhy
in thread Mapping array over a hash by agoth

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