Internal and external iteration, fibers

[deadalnix]

On Thursday, 24 January 2013 at 13:59:43 UTC, David Nadlinger 
wrote:
> On Thursday, 24 January 2013 at 07:55:37 UTC, Jacob Carlborg 
> wrote:
>> On 2013-01-24 03:35, deadalnix wrote:
>>
>>> SDC does something similar with LLVM JIT capabilities.
>>
>> That's the correct approach.
>
> The question is not so much about correctness, but about 
> performance.
>
> Building an LLVM function and JIT-compiling it every time you 
> need to evaluate a D expression will completely ruin your 
> compile times (and I say that as an LLVM proponent). The idea 
> itself is interesting for computationally heavy CTFE code, but 
> I don't think it is feasible to go without lightweight code at 
> least for simple »constant folding«-type applications.
>

This is what SDC does currently, but yes, simple constant folding 
should avoid doing that.

But 1/ make it work and 2/ make it fast.

Current implementation permit easily to add constant folding 
later.