Forwarding a declared class member

Is it possible to forward-declare a class that is declared in another forward-declared class?

Basically, I have something like this

//A.h
class A
{
...
    struct B
    {
    ...
    };
};

      

        
        
        
      

    

and now I want to declare another class like this

//Q.h

class A;
struct A::B;

class Q
{
    A::B* Foo();
};