//bynameorpointer.cpp
//observe what happens when we access
//base class member functions and
//derived class member functions
//from
//   an object name
//   a pointer to the base class
//   a pointer to the derived class

#include<iostream.h>  //cout, endl
using namespace std;

#include "dog.h"
#include "mammal.h"

//#define BYNAMEORPOINTER_CPP
#ifdef BYNAMEORPOINTER_CPP
int main()
  {
    {
  //an object of the base class
  cout << "AN OBJECT OF THE BASE CLASS CAN \n"
    << "ONLY USE BASE CLASS MEMBER FUNCTIONS."
    << endl;

  Mammal m;
  m.Speak();
  m.Sleep();
  m.Identify();
  //m.WagTail();
    }

    {
  //an object of the derived class
  cout << "\n\nAN OBJECT OF THE DERIVED CLASS\n"
    << "CAN USE BASE CLASS AND DERIVED CLASS\n"
    << "MEMBER FUNCTIONS." << endl;
  Dog d;
  d.Speak();
  d.Sleep();
  d.Identify();
  d.WagTail();
    }

    {
  //pointer to base class
  cout << "\n\nA POINTER TO THE BASE CLASS\n"
    << "THAT POINTS TO AN OBJECT OF "
    << "THE BASE CLASS\n"
    << "CAN USE BASE CLASS MEMBER "
    << "FUNCTIONS ONLY." << endl;
  Mammal* pM=new Mammal;
  pM->Speak();
  pM->Sleep();
  pM->Identify();
  //pM->WagTail();
  delete pM;
    }

    {
  //pointer to the derived class
  cout << "\n\nA POINTER TO THE DERIVED CLASS\n"
    << "THAT POINTS TO AN OBJECT OF THE "
    << "DERIVED CLASS\n"
    << "CAN USE BASE CLASS AND DERIVED\n"
    << "CLASS MEMBER FUNCTIONS." << endl;
  Dog* pD=new Dog;
  pD->Speak();
  pD->Sleep();
  pD->Identify();
  pD->WagTail();
  delete pD;
    }

    {
  //pointer to the base class, 
  //    pointing to object of derived class
  cout << "\n\nA POINTER TO THE BASE CLASS\n"
    << "THAT POINTS TO AN OBJECT OF THE "
    << "DERIVED CLASS\n"
    << "CAN USE MEMBER FUNCTIONS DEFINED "
    << "IN THE BASE CLASS.  \n**BUT** IT "
    << "WILL USE THE VERSION DEFINED IN \nTHE "
    << "BASE CLASS FOR NON-VIRTUAL FUNCTIONS\n"
    << "AND THE VERSION DEFINED IN THE "
    << "DERIVED CLASS\nFOR VIRTUAL FUNCTIONS"
    << ", IF ONE EXISTS." << endl;
  Mammal * pM=new Dog;
  pM->Speak();
  pM->Sleep();
  pM->Identify();
  //pM->WagTail();
  delete pM;
    }

  return 0;
  }
  
  #endif