日积月累: Uncopyable && Uninheritable in C++

如何在C++中阻止复制和继承呢，我做了个整理。

Uncopyable

有些类需要禁止被复制或者赋值，这需要显示的禁掉它们的拷贝构造和赋值函数。

摘自《Effective C++》Item 6: Explicitly disallow the use of compiler-generated functions you do not want

class Uncopyable 
{
protected:                                   // allow construction
    Uncopyable() {}                       // and destruction of
    ~Uncopyable() {}                     // derived objects...

private:
    Uncopyable(const Uncopyable&);             // ...but prevent copying
    Uncopyable& operator=(const Uncopyable&);
};

class UncopyableExample: private Uncopyable 
{ 
    // THIS CLASS IS UNCOPYABLE
}; 

Uninheritable

Java提供了final关键字用来阻止被继承，而在C++中没有这个关键字，但阻止继承的类在C++中是同样可能的。

摘自：http://www.csse.monash.edu.au/~damian/Idioms/Topics/04.SB.NoInherit/html/text.html

template <class OnlyFriend>
class Uninheritable
{
    friend class OnlyFriend;
    Uninheritable(void) {}
};

class NotABase : virtual public Uninheritable< NotABase >
{
    // WHATEVER
};

class NotADerived: public NotABase
{
    // THIS CLASS GENERATES A COMPILER ERROR
    NotADerived(){}
};