I just want to be sure that I understand the copy and move semantics. Can you please review the code and see if you can find any bugs.
// HEADER FILE
#pragma once
#include <string>
class Data {
public:
Data(int number); // Constructor
~Data(); // Destructor
Data(const Data&); // Copy constructor
Data(Data&&); // Move constructor
Data& operator=(const Data&); // Copy assignment operator
Data& operator=(Data&&); // Move assignment operator
private:
void swap(Data& w);
private:
int m_number;
};
class Wrapper{
public:
Wrapper(std::string name, int number); // Constructor
~Wrapper(); // Destructor
Wrapper(const Wrapper&); // Copy constructor
Wrapper(Wrapper&&); // Move constructor
Wrapper& operator=(const Wrapper&); // Copy assignment operator
Wrapper& operator=(Wrapper&&); // Move assignment operator
private:
void swap(Wrapper& w);
private:
std::string m_name;
Data* m_pData;
};
// CPP FILE
#include "StdAfx.h"
#include "Wrapper.h"
Wrapper::Wrapper(std::string name, int number) : m_name(name), m_pData(new Data(number)) { // Constructor
}
Wrapper::~Wrapper() {
if (m_pData) {
delete m_pData;
m_pData = nullptr;
}
}
Wrapper::Wrapper(const Wrapper& other) : m_name(other.m_name),
m_pData(new Data(*other.m_pData)) { // Copy constructor
}
Wrapper::Wrapper(Wrapper&& other) : m_name(std::move(other.m_name)),
m_pData(std::move(other.m_pData)) { // Move constructor
other.m_pData = nullptr;
}
Wrapper& Wrapper::operator=(const Wrapper& other) { // Copy assignment operator
Wrapper(other).swap(*this);
return *this;
}
Wrapper& Wrapper::operator=(Wrapper&& other) { // Move assignment operator
std::swap(*this, other);
return *this;
}
void Wrapper::swap(Wrapper& w) throw() {
std::swap(this->m_name, w.m_name);
std::swap(this->m_pData, w.m_pData);
}
/***********************************************************************************************
DATA CLASS IMPLEMENTATION.
***********************************************************************************************/
Data::Data(int number) : m_number(number) { // Constructor
}
Data::~Data() {
}
Data::Data(const Data& other) : m_number(other.m_number) { // Copy constructor
}
Data::Data(Data&& other) : m_number(std::move(other.m_number)) { // Move constructor
}
Data& Data::operator=(const Data& other) { // Copy assignment operator
Data(other).swap(*this);
return *this;
}
Data& Data::operator=(Data&& other) { // Move assignment operator
std::swap(*this, other);
return *this;
}
void Data::swap(Data& w) throw() {
std::swap(this->m_number, w.m_number);
}
// MAIN.CPP
#include "stdafx.h"
#include "Wrapper.h"
Wrapper CreateWrapper() {
Wrapper wrapper("My name is temporary wrapper", 3);
return wrapper;
}
int main(int argc, char* argv[])
{
Wrapper w1("My name is w1", 1), w2("My name is w2", 2);
w1 = w2;
Wrapper w3 = w1;
{
Wrapper w4 = CreateWrapper();
}
return 0;
}
