基类重载方法的访问声明

发布于 2024-10-10 16:06:05 字数 528 浏览 1 评论 0原文

假设我们在基类中重载了方法，并且派生类被继承为私有/受保护。

我们可以只恢复重载方法的一个/几个原始访问级别吗？
在 GCC 4.4.0 上，我尝试将基本方法置于受保护访问之下，然后使用私有访问继承它。当我尝试恢复公共访问级别时，它起作用了！这是它应该如何工作的吗？或者是编译器上的错误？据我了解，恢复访问级别不应用于提升或降级成员的访问级别。

代码片段：

class base {
  public:
    void method() {}
    void method(int x) {}
  protected:
    void method2() {}
};

class derived : private base {
  public:
    base::method; // Here, i want to restore only the none parameterized method
    base::method2; // method2 is now public??
};

原文

Given that we have overloaded methods in base class, and a derived class that was inherited as private/protected.

Can we restore only one/several of the original access level of the overloaded methods?
On GCC 4.4.0 i try to put the base methods under protected access, then inherited it using private access. When i try to restore the access level to public, it works! Is this how its suppose to work? or is it a bug on the compiler? To my understanding, restoring access level shouldn't be able to be used to promote or demote a member's access level.

Code snippet :

class base {
  public:
    void method() {}
    void method(int x) {}
  protected:
    void method2() {}
};

class derived : private base {
  public:
    base::method; // Here, i want to restore only the none parameterized method
    base::method2; // method2 is now public??
};

分享到QQ

分享到微博

如果你对这篇内容有疑问，欢迎到本站社区发帖提问参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

发布评论

需要登录才能够评论，你可以免费注册一个本站的账号。

但可醉心 2024-10-17 16:06:05

通过 using 声明更改继承函数的可访问性无法在给定的重载上有选择地进行，原因很简单，using 声明仅引入一个名称 进入声明性区域，并且根据定义，函数重载共享相同的名称。

我在这里看到的唯一替代方法是使用简单的转发函数：

class derived : private base
{
public:
    void method() { base::method(); }

    using base::method2; // method2 is now public
    // method(int) stays inaccessible
};

我不太确定我是否理解您的第二个问题，但是是的：您可以通过 using 声明更改派生类中的基成员可访问性。

Changing accessibility of inherited functions through a using declaration cannot be done selectively on given overload for the simple reason that a using declaration only introduces a name into the declarative region and that by definition, functions overloads share the same name.

The only alternative I see here is to use trivial forwarding functions :

class derived : private base
{
public:
    void method() { base::method(); }

    using base::method2; // method2 is now public
    // method(int) stays inaccessible
};

I'm not quite sure I understand your second question, but yes : you can change base members accessibility in a derived class through using declarations.

回复收藏 0 原文