Internal and external iteration, fibers

[Rob T]

On Monday, 21 January 2013 at 19:23:19 UTC, Jacob Carlborg wrote:
> I know people don't like it but I have to say, this seems it 
> could be a job for AST macros.

It would be just as ugly as C macros. Well maybe not as ugly, but 
D should have direct support for co-routines, it's an important 
feature with plenty of uses.

BTW, has anyone in here has experience working with Simula? 
Co-routines as a language feature has been around for decades in 
a proven way.

--rt