在C ++ 11中的析构函数之后覆盖标识符 [英] Override identifier after destructor in C++11

问题描述

在虚拟析构函数声明之后的覆盖标识符是否有特殊含义?

Does the override identifier after virtual destructor declaration have any special meaning?

class Base
{
public:
    virtual ~Base()
    {}

    virtual int Method() const
    {}
};

class Derived : public Base
{
public:
    virtual ~Derived() override
    {}

    virtual int Method() override // error: marked override, but does not override - missing const
    {}
};

在虚拟方法上使用覆盖标识符非常有用，可作为检查:当实际上不覆盖基本虚拟方法时，编译器将报告错误.

Using override identifier on virtual method is useful as check: compiler will report error when the Base virtual method is actualy not overriden.

在虚拟析构函数上进行重写是否也具有任何意义/功能?

Does override on virtual destructor has any meaning/function too?

推荐答案

不是override具有特殊含义，而是析构函数本身:

It is not override that has special meaning, but the destructor itself:

6/即使不继承析构函数，派生函数中的析构函数 class覆盖声明为virtual的基类析构函数；见12.4和 12.5.

6/Even though destructors are not inherited, a destructor in a derived class overrides a base class destructor declared virtual; see 12.4 and 12.5.

如果将其与上一条结合使用:

If you take this in conjunction with the previous clause:

5/如果用virt-specifier覆盖标记了虚拟功能，并且 不覆盖基类的成员函数，该程序是 格式不正确. [示例:

5/If a virtual function is marked with the virt-specifier override and does not override a member function of a base class, the program is ill-formed. [ Example:

struct B { 
    virtual void f(int); 
}; 

struct D : B
{ 
    void f(long) override; // error: wrong signature overriding B::f
    void f(int) override; // OK 
}; 

-结束示例]

您会看到，如果将析构函数标记为override，但是基类没有virtual析构函数，则程序格式错误.

you can see that if a destructor is marked override but the base class does not have a virtual destructor, the program is ill-formed.

这篇关于在C ++ 11中的析构函数之后覆盖标识符的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！