title: Inheriting friendship in C++?
body: <p>Since class friendship is not inherited in C++, what's the best way to "fake" it?</p>
  
  <p>I was thinking about exposing the friend class's private interface through protected methods in the to-be-inherited base-class, but that results in having to write (and maintain) the same interface twice.</p>
  
  <p>Are there any other ways?</p>