std.range.chunk without length

[monarch_dodra]

On Thursday, 13 February 2014 at 14:45:44 UTC, bearophile wrote:
> Stephan Schiffels:
>
>> It would be actually easy to implement chunks without the 
>> "save" function, by using an internal buffer, which would 
>> however make this algorithm's memory burden linear in the 
>> chunk size. Would that be acceptable?
>
> I think it's acceptable. But perhaps you need to add one more 
> optional argument for the buffer :-)
>
> Bye,
> bearophile

Users andralex:
https://github.com/D-Programming-Language/phobos/pull/1186

And quickfur:
https://github.com/D-Programming-Language/phobos/pull/1453

Have submitted different algorithms for a similar problem: 
Basically, bu being "2-dimensional lazy" (each subrange is itself 
a lazy range). However, both come with their own pitfalls.

Andrei's still requires forward ranges. quickfur's doesn't, and, 
arguably, has a simpler design. However, if I remember correctly, 
it is also less efficient (it does double work). Implementing 
Quickfur's solution in Chunks for input ranges only could be a 
good idea.

It *is* extra work, more code, more code to cover (that is 
difficult to cover). I'm not sure we have the man power to 
support such complexity: I was able to make chunks work with 
forward ranges, but I still haven't even fixed Splitter yet! I 
think that should take precedence.