Re: HASH Array advice

[serf]

There's no specific reason not to.

If you are only making a small hash (with low numbers) you may find that an array is easier and more efficient *but* there are benefits in using a hash this way over using an array:

Particularly if you have to use a very large index number in the array; I believe that an array is created with (empty where not defined) elements up to the size of the highest index number, so by using a large index number you are pre-allocating (and therefore wasting) a chunk of un-needed memory.

On the other hand with an array you can just do:

for my $element (@array)

and get all the elements back in order (which may or may not be useful in the case you are looking at), whereas with a hash you would have to sort the keys:

for my $key (sort keys %hash)

or explicitly ask for them:

for my $key (@array_of keys)

(which obviously means using a hash *and* an array!) because a hash does not store the keys (or values) in numerical order.