C++学习笔记

11/4/16-01:

如果你想禁止某些东西，就应该把完成它的操作定义为一个私用的成员函数。（the design and evolution of cpp）

如1）只要将析构函数声明为私用就可以避免堆栈和全局分配，这样做还能防止随便使用delete:

class sample{~sample(); // private destructorpublic:static void free(sample* p) { delete p; }};sample global; // error: private destructorvoid f(){sample loc; // errorsample* p = new sample; // fine...delete p; // errorsample::free(p); // fine}

 

2)声明一个不大寻常的operator new(), 只允许全局和堆栈变量，禁止自由空间分配;

class sample{class Dummy {};void* operator new(size_t, Dummy);};sample glob; //finevoid g(){sample loc; //finesample* p = new sample; // error}

3) 对派生的控制, 一个比较tricky的方法

class Usable_lock {friend Usable;private:Usable_lock() {}}class Usable : public virtual Usable_lock {//...public:Usable();Usable(char*);//...};Usable a;class DD : public Usable {};DD dd; // error: DD::DD() cannot access Usable_lock::Usable_lock(): private member

 

11/4/16-02: 操作符重载 prefix ++ and postfix ++

class Ptr_to_X {X& operator++(); // prefixX operator++(int); // postfix}

 

11/4/22 __FUNCTION__ Macro get the name of a function as a string