为什么我不能使用protected / private继承访问派生实例中受保护的基类成员？

Question

我认为可以通过Derived类的实例（或派生自Derived类的任何类，可以访问Base类的受保护成员，因为它们公开从后者继承）。

但是在尝试在以下列表中执行此操作时出现错误。那我错过了什么？

class Base{
private:
  virtual void f(){cout << "f of Base" << endl;}

public:
  virtual ~Base(){}
  virtual void g(){this->f();}
  virtual void h(){cout << "h of Base "; this->f();}
};

class Derived: protected Base{
public:
  virtual ~Derived(){}
  virtual void f(){cout << "f of Derived" << endl;}
private:
  virtual void h(){cout << "h of Derived "; this->f();}
};

int main(){
  Base *base = new Base();
  cout << "Base" << endl;
  base->g(); //f of Base
  base->h(); //h of Base f of Base

  Derived *derived = new Derived();
  cout << "Derived" << endl;
  derived->f(); //f of Derived
  derived->g(); //this doesn't compile and I get the error "void Base::g() is inaccessible within this context". Why?
  derived->h(); //this doesn't compile given that h is private in Derived

  delete base;
  delete derived;
  return EXIT_SUCCESS;
}