如何从基类中公开隐藏的重载？

Question

鉴于此代码:

class base {
public:
  string foo() const; // Want this to be visible in 'derived' class.
}

class derived : public base {
public:
  virtual int foo(int) const; // Causes base class foo() to be hidden.
}

如何在不使用调用基类的虚方法重载复制它的情况下使base :: foo()对派生可见？是否using做的伎俩,如果是的话,它在哪里去了,是不是这样？

class derived : public base {
public:
  virtual int foo(int) const;
  using base::foo;
}

Answer 1

很抱歉回答简短，但是是的。它完全像这样并且做你想做的事：

class derived : public base {
public:
  virtual int foo(int) const;
  using base::foo;
};

另请注意，即使没有：您也可以访问基础using：

derived x;
string str = x.base::foo(); // works without using