RFC on range design for D2

[Andrei Alexandrescu]

BCS wrote:
> Reply to Andrei,
> 
>> Hello,
>>
>> Walter, Bartosz and myself have been hard at work trying to find the
>> right abstraction for iteration. That abstraction would replace the
>> infamous opApply and would allow for external iteration, thus paving
>> the way to implementing real generic algorithms.
> 
> First of all, I /Like/ opApply. I know there are issues with it so I'd 
> rather see it supplemented rather than replaced.

We all like the way it looks. Ranges will preserve its syntax within a 
much more efficient and expressive implementation.

Andrei