C++ How to Program, 10/e

19.2 Self-Referential Classes

A self-referential class contains a member that points to a class object of the same class type. For example, the definition

class Node {
public:
   explicit Node(int); // constructor
   void setData(int); // set data member
   int getData() const; // get data member
   void setNextPtr(Node*); // set pointer to next Node
   Node* getNextPtr() const; // get pointer to next Node
private:
   int data; // data stored in this Node
   Node* nextPtr; // pointer to another object of same type
};

defines a type, Node. Type Node has two private data members—integer member data and pointer member nextPtr. Member nextPtr points to an object of type Node—an object of the same type as the one being declared here, hence the term self-referential ...