In the case of $a[100][42] = pi, obviously there is autovivification. That has no difference from $a->{"a"}{"a"} = pi.

Whether $a[100] makes $a[0] through $a[99] autovivified is not a black white thing, and I am not the first person who classifies that as autovivification. When it is valid to look at this from a perl internal point of view as you did, it is at least not less valid to look at this from a logical point of view. Look at this:

use strict;
use warnings;

my @as;
$as[10] = 0;
for my $a (@as) {
    print ".";
}

[download]

this will print 11 dots, not 1 or 12.

To further pursuit a single correct answer to this question is not very useful, as autovivification is not a clearly defined concept, but rather a commonly used not-clearly-defined terminology that is often expressed through examples.

In reply to Re^3: Should this happen? by pg
in thread Should calling 'exists' create a hash key? by mje

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