[simcop2387]

Not quite, references were introduced in perl 5, in perl 4 and earlier had a different method that wasn't quite multi-dimensional arrays but tried to behave that way.

    $hash{1,2,3} = 10;

This actually ends up doing the following

    $hash{join($;, 1, 2, 3)} = 10;

It builds up a single key from the list using the special variable $; as a separator to the elements. With perl 5 you gained the ability to make references which allow you to actually make multiple dimensions and to do it on arrays, not just hashes.

    $array[1][2][3] = 10;

That also allows for more complicated data structures and much easier ways to iterate through the structures.

[abacadaba]

hmm, it's been 4-5 years since i really did any perl but i remember it being way more confusing than that. maybe i was just a noob.