Re: Function pointer and functor problem
So the queue would be like:
typedef void (*ptr)( );
queue<ptr> timer_queue;
Can it be done somehow using wrapper static functions of classes A and
B ??
Please provide some hint or guidance.
I think the most straightforward solution is to change the callbacks
so they take a single void* pointer as an argument. Then you can have
static
member functions in classes A and B, which static_cast<> the void*
parameter to their own class type and call a non-static member
function on that pointer:
struct Callback {
typedef void (*func_ptr)(void*);
func_ptr f;
void *param;
explicit Callback(func_ptr f_ = 0, void *param_ = 0) : f(f_),
param(param_) {}
};
queue<Callback> timer_queue;
struct A {
static void static_callback(void* self) {
static_cast<A*>(self)->callback();
}
void callback() {
}
};
A a;
timer_queue.push_back(Callback(A::static_callback, &a));
This is not strictly type-safe, so you have to be careful, but for the
simple-sounding case you are describing it is perfectly reasonable.
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