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//Download by http://www.NewXing.com /* * This file contains code from "C++ Primer, Fourth Edition", by Stanley B. * Lippman, Jose Lajoie, and Barbara E. Moo, and is covered under the * copyright and warranty notices given in that book: * * "Copyright (c) 2005 by Objectwrite, Inc., Jose Lajoie, and Barbara E. Moo." * * * "The authors and publisher have taken care in the preparation of this book, * but make no expressed or implied warranty of any kind and assume no * responsibility for errors or omissions. No liability is assumed for * incidental or consequential damages in connection with or arising out of the * use of the information or programs contained herein." * * Permission is granted for this code to be used for educational purposes in * association with the book, given proper citation if and when posted or * reproduced.Any commercial use of this code requires the explicit written * permission of the publisher, Addison-Wesley Professional, a division of * Pearson Education, Inc. Send your request for permission, stating clearly * what code you would like to use, and in what specific way, to the following * address: * * Pearson Education, Inc. * Rights and Contracts Department * 75 Arlington Street, Suite 300 * Boston, MA 02216 * Fax: (617) 848-7047 */ #include <iostream> using std::cout; using std::endl; #include "Handle.h" int main() { { // new scope // user allocates but must not delete the object to which the Handle is attached Handle<int> hp(new int(42)); { // new scope Handle<int> hp2 = hp; // copies pointer; use count incremented cout << *hp << " " << *hp2 << endl; // prints 42 42 *hp2 = 10; // changes value of shared underlying int } // hp2 goes out of scope; use count is decremented cout << *hp << endl; // prints 10 } // hp goes out of scope; its destructor deletes the int }