Circular Buffer

[Andrea Fontana]

On Tuesday, 11 February 2014 at 16:30:42 UTC, Rene Zwanenburg 
wrote:
> On Tuesday, 11 February 2014 at 16:26:06 UTC, Rene Zwanenburg 
> wrote:
>> On Tuesday, 11 February 2014 at 03:10:02 UTC, Jonathan Dunlap 
>> wrote:
>>> Wow! This is GREAT stuff. My use-case is slightly more 
>>> complex, and I'm not sure how to best apply this knowledge. 
>>> The retro reverses the array which is problematic in itself 
>>> as well as losing the starting index location. I have an 
>>> array that I'd like to elegantly "rotate". Best way I can 
>>> show this is by example of an imaginary rotate function:
>>>
>>> auto data = [1,2,3];
>>> assert( data.cycle.rotate(2) == [3,1,2] );
>>> assert( data.cycle.rotate(-2) == [2,3,1] );
>>>
>>> Perhaps what I'm doing is too complex requires me making my 
>>> own iterator or something. In my quest of writing readable 
>>> efficient code, I'm wondering what's the best route here. 
>>> Thanks :)
>>
>> Perhaps something like this?
>> http://dpaste.dzfl.pl/d4b82b0b5cba
>
> Wait, we can avoid creating that closure and eliminate the map. 
> This should be a bit faster and not use the GC:
>
> http://dpaste.dzfl.pl/78c65eacfeb1

Why not drop and take?
http://dpaste.dzfl.pl/0649b809c81e