【运维经】第45章——marked override, but does not override

运维经–目录marked override, but does not overridec++11中引入了override关键字，被override修饰的函数其派生类必须重载。#include <iostream>class Object{public:Object(){};virtual ~Object(){};virtual void...

夏克

16357人浏览 · 2020-03-09 11:00:32

夏克 · 2020-03-09 11:00:32 发布

运维经–目录

marked override, but does not override

c++11中引入了override关键字，被override修饰的函数其派生类必须重载。

#include <iostream>

class Object
{
public:
    Object(){};
    virtual ~Object(){};

    virtual void fun() override
    {
        std::cout << "Object::fun" << std::endl;
    }
};

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

    void fun();
};
void Base::fun()
{
    std::cout << "Base::fun" << std::endl;
}

int main(){
    Object* b = new Base;
    b->fun();
    return 0;
}

编译：

[frank@LAPTOP-0OCJTGJR class]$ g++ -g -std=c++11 test_class.cpp

test_class.cpp:9:18: error: ‘virtual void Object::fun()’ marked override, but does not override
     virtual void fun() override
                  ^