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ex13_13.cpp
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ex13_13.cpp
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//
// ex13_13.cpp
// CP5
//
// Created by pezy on 1/13/15.
// Copyright (c) 2015 pezy. All rights reserved.
//
// A good way to understand copy-control members and constructors is to define a simple class with these members in which each member prints its name:
// struct X {
// X() {std::cout << "X()" << std::endl;}
// X(const X&) {std::cout << "X(const X&)" << std::endl;}
// };
// Add the copy-assignment operator and destructor to X and write a program using X objects in various ways:
// Pass them as nonreference and reference parameters;
// dynamically allocate them;
// put them in containers; and so forth.
// Study the output until you are certain you understand when and why each copy-control member is used.
// As you read the output, remember that the compiler can omit calls to the copy constructor.
#include <iostream>
#include <vector>
#include <initializer_list>
struct X {
X() { std::cout << "X()" << std::endl; }
X(const X&) { std::cout << "X(const X&)" << std::endl; }
X& operator=(const X&) { std::cout << "X& operator=(const X&)" << std::endl; return *this; }
~X() { std::cout << "~X()" << std::endl; }
};
void f(const X &rx, X x)
{
std::vector<X> vec;
vec.reserve(2);
vec.push_back(rx);
vec.push_back(x);
}
int main()
{
X *px = new X;
f(*px, *px);
delete px;
return 0;
}