ebco1.cpp

来自「非常著名的C++ Templates 完全导引范例配套的原代码」· C++ 代码 · 共 32 行

/* The following code example is taken from the book
 * "C++ Templates - The Complete Guide"
 * by David Vandevoorde and Nicolai M. Josuttis, Addison-Wesley, 2002
 *
 * (C) Copyright David Vandevoorde and Nicolai M. Josuttis 2002.
 * Permission to copy, use, modify, sell and distribute this software
 * is granted provided this copyright notice appears in all copies.
 * This software is provided "as is" without express or implied
 * warranty, and with no claim as to its suitability for any purpose.
 */
#include <iostream>

class Empty {
    typedef int Int;  // typedef members don't make a class nonempty
};

class EmptyToo : public Empty {
};

class EmptyThree : public EmptyToo {
};

int main()
{
    std::cout << "sizeof(Empty):      " << sizeof(Empty)
              << '\n';
    std::cout << "sizeof(EmptyToo):   " << sizeof(EmptyToo)
              << '\n';
    std::cout << "sizeof(EmptyThree): " << sizeof(EmptyThree)
              << '\n';
}