From: Phillip Hutchings <sitharus@...>
Date: 2006-08-21T11:04:55+09:00
Subject: Re: Why Does Hash Apparently Reorder Its Internal Representation And Other Associated Ponderings

On 8/21/06, thoran @ thoran. com <thoran@thoran.com> wrote:
> I was surprised to find the following...

Really? Take a comsci course at uni

> I realise that it is a hash and that access is expected to be by key,
> but sometimes retaining the presented order may be desired.  And
> anyway, why reorder it at all?

It's not 'reordered', it's stored in a hash table. Think of how MD5
represents a unique key for almost every possible value, but the hash
has no real connection to the original value. A hash table is stored
using similar keys, though you are allowed duplicate keys for a hash
table, and if you go in to the mathematical theory of it there is a
lot of speed gained this way especially if you're using large keys,
such as in i18n applications where each string is stored in a hash
table. That's why it's called a hash and not an array.

-- 
Phillip Hutchings
http://www.sitharus.com/