[Python-Dev] Re: [Stackless] comments on PEP 219

[Guido van Rossum]

> Christian Tismer <tismer@tismer.com>:
> 
> > But stopping the interpreter is a perfect unwind, and we
> > can start again from anywhere.
> 
> Hmmm... Let me see if I have this correct.
> 
> You can switch from uthread A to uthread B as long
> as the current depth of interpreter nesting is the
> same as it was when B was last suspended. It doesn't
> matter if the interpreter has returned and then
> been called again, as long as it's at the same
> level of nesting on the C stack.
> 
> Is that right? Is that the only restriction?

I doubt it.  To me (without a lot of context, but knowing ceval.c :-)
it would make more sense if the requirement was that there were no C
stack frames involved in B -- only Python frames.

--Guido van Rossum (home page: http://www.python.org/~guido/)