Question

Is it possible to have a base class that has an instance of the derived class as a parameter to one of the base class’s functions? For example:

class A
{
  virtual void foo(B b[]);
};
Class B: public A
{
  void foo(B b[]);
};

Is this legal? Also class A will need to include the header file for class B, is this problematic as well?

Answer 1

It’s possible with a forward declaration:

class B;
class A
{
  virtual void foo(B b[]);
};
Class B: public A
{
  void foo(B b[]);
};

but it’s a major code smell. Please state what you’re trying to achieve, this looks like a faulty design.