Re: [TCLCORE] Coroutines in HEAD

[miguel s. <mig...@gm...>]

Lars Hellström wrote:
> Ultimately, we may always fall back to what is written on the tape of 
> our Turing machine. :-) More practically, also the NRE has to separate 
> the per-coroutine state from the general interpreter state, and IMHO 
> that is where you might encounter nontrivial issues. The rest should 
> just be the hard work of serializing a well-defined data structure.

Not so, NRE does not separate the per-coroutine execution environment when 
[yield] is called. Those execEnvs are born separate, that's the main job of the 
[coroutine] command.

The generated command for the coroutine just swaps the coroutine's execEnv into 
the interp (swapping a couple of pointers), registers a callback to swap back 
the original exexcEnv on return, and runs. Later [yield] saves the relevant 
pointers into a CoroutineData struct and returns, letting the callback restore 
the caller's environment.