DIP 50 - AST macros

[deadalnix]

On Thursday, 14 November 2013 at 10:07:31 UTC, Chris Cain wrote:
> On Thursday, 14 November 2013 at 09:12:38 UTC, Walter Bright 
> wrote:
>> I agree that async/await has to eventually be added to D. I'm 
>> not convinced it can or should be done with AST macros.
>
> Out of curiousity, how would that be implemented without 
> macros? I could see it being done with macros with a rewrite 
> and using some of the standard library (like std.parallelism), 
> maybe. But with a language feature, you couldn't use the 
> standard library. It seems like some parallelism code would 
> have to leak into the runtime to get it to work as people might 
> expect.
>
> I guess I would have thought the exact opposite from you... 
> that this is precisely something that *should* be done with a 
> library-defined macro.

async await do not create parallelism.