// Fig. 9.16: fig09_16.cpp // Demonstrating a public member function that // returns a reference to a private data member. #include using std::cout; using std::endl; #include "Time.h" // include definition of class Time int main() { Time t; // create Time object // initialize hourRef with the reference returned by badSetHour int &hourRef = t.badSetHour( 20 ); // 20 is a valid hour cout << "Valid hour before modification: " << hourRef; hourRef = 30; // use hourRef to set invalid value in Time object t cout << "\nInvalid hour after modification: " << t.getHour(); // Dangerous: Function call that returns // a reference can be used as an lvalue! t.badSetHour( 12 ) = 74; // assign another invalid value to hour cout << "\n\n*************************************************\n" << "POOR PROGRAMMING PRACTICE!!!!!!!!\n" << "t.badSetHour( 12 ) as an lvalue, invalid hour: " << t.getHour() << "\n*************************************************" << endl; return 0; } // end main /************************************************************************** * (C) Copyright 1992-2005 by Deitel & Associates, Inc. and * * Pearson Education, Inc. All Rights Reserved. * * * * DISCLAIMER: The authors and publisher of this book have used their * * best efforts in preparing the book. These efforts include the * * development, research, and testing of the theories and programs * * to determine their effectiveness. The authors and publisher make * * no warranty of any kind, expressed or implied, with regard to these * * programs or to the documentation contained in these books. The authors * * and publisher shall not be liable in any event for incidental or * * consequential damages in connection with, or arising out of, the * * furnishing, performance, or use of these programs. * **************************************************************************/