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

运维经–目录

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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 

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
                  ^