From: Mark Hubbart <discord@...>
Date: 2004-03-03T17:37:00+09:00
Subject: Re: why are Hashes so unsorted? what's your solution?


On Mar 2, 2004, at 11:33 PM, Lothar Scholz wrote:

> Hello David,
>
> Wednesday, March 3, 2004, 6:33:01 AM, you wrote:
>
>
> DN> Simplest solution: use an ordered hash implementation, such as 
> rbtree
>
> Please don't use this term "ordered hash" anymore. It is just stupid
> wrong. You may refer to a "hash" or a "tree" (balanced or not). If
> someone asking about an ordered hash just point out that he is
> expecting something that does not exist in the known universe.

The problem in terms here is that PHP blurs the lines between hashes, 
arrays, whatever you want to call them. There is just one construct, 
which they call an Array. Each item in the array can have both a hash 
key (a string) and an index (an integer). if you write "myarray['test'] 
= item", an index automatically gets created in addition to the hash 
key.
Additionally, PHP arrays have an order, which is not necessarily the 
same as the order given by the indices. In fact, it is *very* often 
different. Usually it is the order in which items were added to the 
array. Calling "each()" iterates over the array in the hidden order. If 
you want, you can sort the array/hash by the internal/hidden ordering, 
and indices and hashes are unchanged, but iterating over it with 
"each()" is different.

Of course, this sounds confusing all thrown together like this, but it 
really isn't that bad. You can do some nifty tricks, all because of the 
strange hybrid php hash/lists. :)

--Mark