Revised RFC on range design for D2

[Andrei Alexandrescu]

Sergey Gromov wrote:
> Andrei Alexandrescu <SeeWebsiteForEmail at erdani.org> wrote:
>> In wake of the many excellent comments and suggestions made here, I made 
>> one more pass through the draft proposal for ranges.
>>
>> http://ssli.ee.washington.edu/~aalexand/d/tmp/std_range.html
>>
>> There are some comments in red illustrating some uncertainties (not 
>> all), and the names of the primitives have been updated. Bicycle shed 
>> galore! But don't forget to comment on the reactor as well :o).
> 
> I've found superdan's post that convinced you.  I honestly cannot see 
> why.
> 
> Suppose I want to allow recycling in empty/next pair.  Then I cpecify 
> that:
> * next() returns stuff;
> * stuff is guaranteed to survive until the subsequent call to next();
> * stuff becomes undefined after next() is called again;
> * stuff is guaranteed to survive intermediate calls to empty().
> 
> The last point can make implementation more complex in some cases but 
> it's definitely possible to implement.
> 
> If we revert to empty/next, or whateve names you think better, then we 
> can also revert to using first/last for forward/bidirectional range 
> outermost elements and stop that body parts discussion.
> 
> I really hope this makes sense.

He did convince me. With your API you can't write efficient algorithms 
that work with input ranges and forward ranges crawling on actual 
containers.

Andrei