Thread: A treatise on friend is needed

Oh, and you might want B's print() to show the inherited part of the object by calling A's print():

Code:

class B : public A
{
    public:

        virtual void print (std::ostream & os) const
        {
             os << "Object of class B. Base: ";
             A::print (os);
        }
//...

In this case, if you decide to hide print() from the clients, you would have to make it protected, not private.

If I leave print() public, you might argue that my operator<< is just syntax sugar, but... yum! :-)