NonCopyable

class NonCopyable {
public:
    NonCopyable()                    = default;
    NonCopyable(const NonCopyable&)  = delete;
    NonCopyable(const NonCopyable&&) = delete;
    NonCopyable& operator=(const NonCopyable&) = delete;
    NonCopyable& operator=(const NonCopyable&&) = delete;
};

禁止拷贝的基类