Also, I still don't understand why the 'wrong' version creates the data structure that it does. Any thoughts on that one?
 
use strict;
use warnings;
use 5.010;

use Data::Dumper;

my @arr = ();
$arr[3] = 40;
say Dumper(\@arr);

--output:--
$VAR1 = [
          undef,
          undef,
          undef,
          40
        ];

[download]

And from the Data::Dumper docs:

... duplicate references to substructures within $VARn will be appropriately labeled using arrow notation.

The second element of your $VAR1 array is a duplicate reference, and instead of bothering to print it out again, Data::Dumper essentially says, "If you want to see what the second element looks like, go look at the first element, $VAR1->[0], because I won't be bothered trying to format that pretty output again.

In reply to Re: Scope and references by 7stud
in thread Scope and references by {}think

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