条款06: 若不想使用编译器自动生成的函数，就该明确拒绝

1. 将Copy构造函数或copy Assignment操作符声明为private
2. 因为member函数和friend函数可以调用private函数，不去定义private函数，当调用时会获得一个链接错误

class HomeForSale00
{
public:
    HomeForSale00() {}
    void GenerateHomeForSale00Member()
    {
        HomeForSale00 home00;
        HomeForSale00 home01;
        //HomeForSale00 home02(home00); //链接错误
        //home00 = home01; //链接错误
    }
private:
    friend void GenerateHomeForSale00Friend();
    HomeForSale00(const HomeForSale00&);
    HomeForSale00& operator=(const HomeForSale00&);
private:
    uint32_t HomePrice;
};

void GenerateHomeForSale00Friend()
{
    HomeForSale00 home00;
    HomeForSale00 home01;
    home00.HomePrice = 200;
    //HomeForSale00 home02(home00); //链接错误
    //home00 = home01; //链接错误
}

void Test00()
{
    HomeForSale00 home00;
    HomeForSale00 home01;
    //HomeForSale00 home02(home00); //private不可访问
    //home00 = home01; //private 不可访问

    GenerateHomeForSale00Friend();

    home00.GenerateHomeForSale00Member();
}

1. 为了阻止copying动作设计Uncopyable的base class
2. 因为Uncopyable class不含数据，因此不一定得以public继承，以及Uncopyable class的析构函数为虚函数

class Uncopyable
{
protected:
    Uncopyable() = default;
    ~Uncopyable() = default;
private:
    Uncopyable(const Uncopyable&) = delete;
    Uncopyable& operator=(const Uncopyable&) = delete;
};

class HomeForSale01:private Uncopyable
{
public:
    HomeForSale01() {}
    void GenerateHomeForSale01Member()
    {
        HomeForSale01 home00;
        HomeForSale01 home01;
        //HomeForSale01 home02(home00); //链接错误
        //home00 = home01; //链接错误
    }
private:
    friend void GenerateHomeForSale01Friend();
    HomeForSale01(const HomeForSale01&);
    HomeForSale01& operator=(const HomeForSale01&);
private:
    uint32_t HomePrice;
};

void GenerateHomeForSale01Friend()
{
    HomeForSale01 home00;
    HomeForSale01 home01;
    home00.HomePrice = 200;
    //HomeForSale01 home02(home00); //链接错误
    //home00 = home01; //链接错误
}

void Test01()
{
    HomeForSale01 home00;
    HomeForSale01 home01;
    //HomeForSale01 home02(home00); //private不可访问
    //home00 = home01; //private 不可访问

    GenerateHomeForSale01Friend();

    home00.GenerateHomeForSale01Member();
}

int main()
{
    Test00();
    Test01();
    return EXIT_SUCCESS;
}