基类中没有子类但仍被调用的友元运算符<<和>>

为什么运营商<&书信电报;并且>>如果它们在调用<&书信电报;并且>>在儿童课堂上?

密码

#include <iostream>
#include <memory>
#include <vector>

using namespace std;

class Baza
{
protected:
    int n;
public:
    Baza() { cout << "B\n"; }
    virtual ~Baza() { cout << "~B\n"; }

    friend istream& operator>>(istream& in, Baza& b);
    friend ostream& operator<<(ostream& out, const Baza& b);
};

istream& operator>>(istream& in, Baza& b)
{
    cout<<"op >>"<<endl;
    return in;
}

ostream& operator<<(ostream& out, const Baza& b)
{
    cout<<"op<<"<<endl;
    return out;
}

class Derivata : public Baza
{
public:
    Derivata() { cout << "D\n"; }
    ~Derivata() { cout << "~D\n"; }


};



int main()
{
    vector<Derivata> v;
    v.push_back(new Derivata);

// works
    Derivata d;
    cin>>d;
    cout<<d;

    return 0;
}

c++编译器是否正在创建一个运算符,该运算符在编译时默认调用基类方法的运算符?

重新表述:在基类(即baza)中定义了运算符<&书信电报;并且>>作为朋友。Derivata类继承了“baza”(基类),但运算符不是继承的,因为它们是朋友。如果我使用>>并且<&书信电报;在“derivata”类中?