Re: Mixed public/private derivation?

From:
"Alf P. Steinbach" <alfps@start.no>
Newsgroups:
comp.lang.c++
Date:
Mon, 15 May 2006 23:13:10 +0200
Message-ID:
<4cs97aF13p8jdU1@individual.net>
* Adam Aulick:

I have a class hierarchy that looks like this:

A -- an interface
B -- an implementation of A
C -- a complex multiply-derived class, using B for its implementation of A.

I want C to expose publicly the many methods of interface A, but not
expose the few public methods defined in B.

I could say:

class C : virtual public A, protected B
{
public:
  //implement each method of A, redirecting to B's implementation
};

But this seems unnecessarily tedious.

Is there a way to announce in the class declaration of C, that I want to
 derive from B, while publicly exposing only A?


   struct A { virtual ~A(){} virtual void foo() = 0; };
   struct B: virtual A { void foo(){} void boo(){} };

   class C: virtual public A, virtual protected B
   {
   public:
       using B::foo;
   };

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