associative arrays: iteration is finally here

[Max Samukha]

On Wed, 28 Oct 2009 09:22:00 -0500, Andrei Alexandrescu
<SeeWebsiteForEmail at erdani.org> wrote:

>Walter has magically converted his work on T[new] into work on making 
>associative arrays true templates defined in druntime and not considered 
>very special by the compiler.
>
>This is very exciting because it opens up or simplifies a number of 
>possibilities. One is that of implementing true iteration. I actually 
>managed to implement last night something that allows you to do:
>
>int[int] aa = [ 1:1 ];
>auto iter = aa.each;
>writeln(iter.front.key);
>writeln(iter.front.value);
>
>Two other iterations are possible: by key and by value (in those cases 
>iter.front just returns a key or a value).
>
>One question is, what names should these bear? I am thinking of makign 
>opSlice() a universal method of getting the "all" iterator, a default 
>that every container must implement.

It looks pretty intuitive to me.

>
>For AAs, there would be a "iterate keys" and "iterate values" properties 
>or functions. How should they be called?

eachKey, eachValue
keyRange, valueRange
keys, values

I'd prefer the last one.

>
>
>Thanks,
>
>Andrei