Revised RFC on range design for D2

[Sergey Gromov]

Andrei Alexandrescu <SeeWebsiteForEmail at erdani.org> wrote:
> Sergey Gromov wrote:
> > *)
> > next() is specified to return a value, but reduce() is not.  This is 
> > probably a typo.  I'd prefer them both be implemented as (done(), head) 
> > and (reduce(), toe) respectively, but I don't know what your intention 
> > was.
> 
> Neither of next and retreat should return a value. In wake of 
> constructors/destructors, we shouldn't return by-value lightly.

Then, in Input range primitives, e=r.next must be just r.next.