#ifndef HASPTR_H
#define HASPTR_H


#include <string>

class HasPtr {
public:
    friend void swap(HasPtr&, HasPtr&);
    HasPtr(const std::string& s = std::string());
    HasPtr(const HasPtr& hp);
    HasPtr(HasPtr&& p) noexcept;
    HasPtr& operator=(HasPtr rhs);
    // HasPtr& operator=(const HasPtr &rhs);
    // HasPtr& operator=(HasPtr &&rhs) noexcept;
    ~HasPtr();

private:
    std::string* ps;
    int i;
};

#endif // HASPTR_H


#include "hasptr.h"
#include <iostream>

inline void swap(HasPtr& lhs, HasPtr& rhs)
{
    using std::swap;
    swap(lhs.ps, rhs.ps);
    swap(lhs.i, rhs.i);
    std::cout << "call swap" << std::endl;
}

HasPtr::HasPtr(const std::string& s) : ps(new std::string(s)), i()
{
    std::cout << "call constructor" << std::endl;
}

//这里的i+1只是为了方便调试的时候看过程，实际是不用加1的
HasPtr::HasPtr(const HasPtr& hp) : ps(new std::string(*hp.ps)), i(hp.i + 1)
{
    std::cout << "call copy constructor" << std::endl;
}

HasPtr::HasPtr(HasPtr&& p) noexcept : ps(p.ps), i(p.i)
{
    p.ps = 0;
    std::cout << "call move constructor" << std::endl;
}

HasPtr& HasPtr::operator=(HasPtr rhs)
{
    swap(*this, rhs);
    return *this;
}

HasPtr::~HasPtr()
{
    std::cout << "call destructor" << std::endl;
    delete ps;
}

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    HasPtr hp1("hello"), hp2("World"), *pH = new HasPtr("World");
    hp1 = hp2;
    hp1 = std::move(*pH);

    return a.exec();
}