Use case: eliminate hidden allocations in buildPath

[monarch_dodra]

On Thursday, 5 December 2013 at 16:46:52 UTC, Andrei Alexandrescu 
wrote:
> On 12/5/13 8:19 AM, monarch_dodra wrote:
>> On Thursday, 5 December 2013 at 15:00:07 UTC, Andrei 
>> Alexandrescu wrote:
>>> Andrei
>>
>> Output range! :)
>>
>> Output range interface makes no linearity requirements. Just 
>> that:
>> "out.put(this)" compiles.
>
> Hrm, construction of a hash table is linearizable so bad 
> example on my part. But I'm talking about general structured 
> data such as objects with allocated fields and connections to 
> other objects etc. etc.
>
> Andrei

Say, something like a graph? At that point, I'd say you'd have to 
pass an "allocating scheme" to the function, so an allocator, 
yes. Depending on the data being generated, the constructed item 
could carry the allocator itself. For example: auto newNode = 
myNode.GenerateNeighbor();

In But I think that'd be a special case situation. For everything 
else, output range is an easy and intuitive, and fits well with 
the rest of phobos. We'd want (IMHO) to integrate the allocators 
directly inside the output ranges.