Generators in D

[Sean Kelly]

On May 17, 2011, at 2:37 PM, Piotr Szturmaj wrote:

> Sean Kelly wrote:
>> On May 11, 2011, at 3:06 PM, Piotr Szturmaj wrote:
>> 
>>> Andrei Alexandrescu wrote:
>>>> * can you implement save() to make this a forward range (e.g. by
>>>> creating a new fiber that has its own state)?
>>> 
>>> It is not that simple I guess. Fiber class doesn't give any opportunity to save
> >> current stack and I think it might be wrong to do this, because of GC issues.
> >> But I don't certainly know.
>>> 
>>> I think that author of the Fiber class could answer this better than me.
>>> If Fiber will expose some additional API, then I would certainly implement save().
>> 
>> Cloning a Fiber would essentially produce a shallow copy--if the Fiber's stack contains
> > references to data elsewhere on the same stack, the clone's stack > would reference the original's.  So while this could be done,
> > I don't think it's advisable.
> 
> But couldn't Fiber's stack be scanned for references to itself and readjusted?

Without type information, there's no way to be sure that something is actually a reference, so corruption could occur.