C++ Primer Plus, Fourth Edition

Special Relationships

A derived class has some special relationships with the base class. One, which you've just seen, is that a derived class object can use base class methods:

RatedPlayer rplayer1(1140, "Mallory", "Duck", true);
rplayer1.Name();  // derived object uses base method

Two other important relationships are that a base class pointer can point to a derived class object without an explicit type cast and that a base class reference can refer to a derived class object without an explicit type cast:

RatedPlayer rplayer1(1140, "Mallory", "Duck", true);
TableTennisPlayer & rt = rplayer;
TableTennisPlayer * pt = &rplayer;
rt.Name();   // invoke Name() with reference
pt->Name();  // invoke Name() with pointer

However, a base class pointer ...