c++ - 结构和类以及继承 (c++)

Question

如果 struct 中的所有访问说明符(包括继承)都是 public，你能向我保证吗？

换句话说:它们相等吗？

class C: public B, public A { public:
    C():A(1),B(2){}
    //...
};

和

struct C: B, A {
    C():A(1),B(2){}
    //...
};

Answer 1

是的，它们都是公开的。

struct A : B {
  C c;
  void foo() const {}
}

相当于

struct A : public B {
 public:
  C c;
  void foo() const {}
}

对于成员，在 §11 中指定:

Members of a class defined with the keyword class are private by default. Members of a class defined with the keywords struct or union are public by default.

对于 §11.2 中的基类:

In the absence of an access-specifier for a base class, public is assumed when the derived class is defined with the class-key struct and private is assumed when the class is defined with the class-key class.

其中引用了 C++11 标准。