Re: Mixed public/private derivation?

From:

"Alf P. Steinbach" <alfps@start.no>

Newsgroups:

comp.lang.c++

Date:

Tue, 16 May 2006 16:57:40 +0200

Message-ID:

<4cu7j8F17fsupU1@individual.net>

* Adam Aulick:

Phlip wrote:

Adam Aulick wrote:

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

I tried without the using statements (there are a large number of them,
and they are still changing periodically)

Why are there many of them? Why don't you pass around a reference to
A, so
clients of B only see A's interface, with the narrow set of methods in
it.

This is called the Interface Segregation Principle, I think.

I do pass around a reference to A, and clients see what I want them to
see at this point, which is good. What I'm trying to avoid is
nit-picky: having code in C's declaration for each method of A, which
causes maintenance the maintenance overhead of changing C's declaration
every time I add or remove a method in A.

   struct C: protected B
   {
       operator A& () { return *this; }
       operator A const& () { return *this; }
   };

Perhaps?

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