wdebug.cpp

C++Primer 经典之作

/*
 * 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: [phone]
*/ 

#include <cassert>
#include <string> 
#include <iostream> 

using std::endl; using std::cerr; using std::cin;
using std::string;

int main() 
{
#ifndef NDEBUG
cerr << "starting main" << endl;
#endif
// ...
    string word = "foo";
    const string::size_type threshold = 5;
    if (word.size() < threshold) 
        cerr << "Error: " << __FILE__
             << " : line " << __LINE__ << endl
             << "       Compiled on " << __DATE__ 
             << " at " << __TIME__ << endl
             << "       Word read was \"" << word 
             << "\":  Length too short" << endl;
    word = "something longer than five chars";
    assert(word.size() > threshold);

    return 0;
}