On Thu, Sep 20, 2012 at 12:17 PM, Vicente J. Botet Escriba < vicente.botet@wanadoo.fr> wrote:
Le 20/09/12 12:18, Giovanni Piero Deretta a écrit :
On Thu, Sep 20, 2012 at 3:51 AM, Vicente J. Botet Escriba <
vicente.botet@wanadoo.fr> wrote:
Note that as I commented in some of my first post related to bind, you must take care of const and reference parameters in some tricky ways, as in order to be able to reassign them you should do some casts. I hope this will not cache some undefined behavior.
How would you exactly rebind references? I can't see any sane way to do it. I would expect the following code to work:
int i = 0, j = 0; coroutine<void(int&)> coro([&](caller_t& caller, int& x) { caller.bind(x); assert(&x == &i); // ok caller.yield(); assert(&x == &y); // ????? });
coro(i); coro(j);
Yes, references could not be rebound. We could rebind types, pointers but not references. I guess the coroutine library could store a pointer on the caller object, and allow to obtain them using get<>. But in this case the coroutine function could not follow the coroutine signature.
you mean that caller_t::yield does not really model "int&()"? Well, this is an issue. As far I understand, currently Oliver is leaning on passing the parameters to the coroutine-fn, having yield() return a tuple, and having the coroutine-fn return the final result. This means that yield() will closely follow the signature and everything is fine. If instead he decides to go with the get<> interface, then maybe it is time to abandon the coroutine as a function model. -- gpd