FAQ 37.06 In a private or protected derived class, how can a member function that was public in the base class be made public in the derived class?

The name (not the entire signature) of the member function should be declared in the public interface of the derived class preceded by the keyword using. For example, to make the member function B::f(int,char,float) public in PrivD, say this:

 class B { public:   int f(int, char, float) throw(); protected:   int g(double, char) throw(); }; class PrivD : private B { public:   using B::f;                                        <-- 1 }; 

(1) Note: Omit the parameter declarations

The syntax for doing this with protected inheritance is identical.

There are two limitations to this technique: overloaded names can't be distinguished, and a base member cannot be made public if it was protected in the base class (that is, this technique cannot be used to make Base::g(double,char) public in the derived class). When necessary, both these limitations can be avoided by defining a call-through member function in the privately/protectedly derived class, as shown in the following example.

 class PrivD2 : private B { public:   int g(double d, char c) throw(); }; inline int PrivD2::g(double d, char c) throw() { return B::g(d, c); }