invalid use of incomplete type

Question

I\'m trying to use a typedef from a subclass in my project, I\'ve isolated my problem in the example below.

Does anyone know where I\'m going wrong?

Answer 1

Not exactly what you were asking, but you can make action a template member function:

template
class A {
    public:
        //Why doesn't it like this?
        template void action(V var) {
                (static_cast(this))->do_action();
        }
};

class B : public A {
    public:
        typedef int mytype;

        B() {}

        void do_action(mytype var) {
                // Do stuff
        }
};

int main(int argc, char** argv) {
    B myInstance;
    return 0;
}