Question

To define these two class

typedef map<C, B::iterator> A;
typedef list<D, A::iterator> B;

The class A and B mutual contain each other’s iterator.
The compiler complains about above statement.
How to solve the problem ?

iammilind says it is impossible. but this logic relationship appears, for example a priority queue. So any one have workaround?

Answer 1

Unfortunately, it’s not possible.
A and B are interdependent, so at least one of them has to be forward declared to support the other.
But the typedef types cannot be forward declared as class/struct.