If I am reading the Cookbook aright, you want to use the PDL module from CPAN. For your example:

use PDL;

$foo = pdl [ 1, 2, 3 ];
$bar = pdl [ 4, 5, 6 ];

$baz = $foo + $bar;
[download]

I'm going to go verify this now, but it looks straightforward. --TQuid