Associative array and ranges

[Steven Schveighoffer]

On Thu, 03 Feb 2011 09:35:44 -0500, Nrgyzer <nrgyzer at gmail.com> wrote:

> == Auszug aus bearophile (bearophileHUGS at lycos.com)'s Artikel
>> Nrgyzer:
>> > Is there any chance to cast/convert this array to an indexed
> array or
>> > is it possible to iterate over specific indices? I know that
> there is
>> > something like next() for the foreach-statement but when the array
>> > contains some thousand instances and I only want iterate over (for
>> > example) 5 elements I think that's the wrong way.
>> Show a hypothetical code example of what you desire to do, please.
>> Bye,
>> bearophile
>
> Example:
>
> ...
> class Example(T : Drawable) : Drawable {
>
> 	T[hash_t] pObjectsToDraw;
>
> 	uint pFrom, pTo;
>
> 	void setLimit(from, to) {
> 		pFrom = from;
> 		pTo = to;
> 	}
>
> 	void remove(T objToRemove) {
> 		pObjectsToDraw.remove(objToRemove.toHash());
> 	}
>
> 	override void draw() {
> 		for (uint i = pFrom; i < pTo; i++) {
> 			pOjectsToDraw[i].draw(); // cannot call
> because pObjectsToDraw is an associative and no static or dynamic
> array
> 		}
> 	}
>
> }

First, hashes are not stored in any particular order, so I'm not sure what  
you expect to accomplish except "give me (pTo - pFrom) random elements  
 from the array"

Second, you can use a foreach loop to get data out of an AA, and then  
break when you've retrieved enough elements.

Again, I'm not sure what the point is of starting in the middle of the  
array.  Are you expecting something different from a hashtable?

-Steve