Path: utzoo!attcan!uunet!peregrine!elroy.jpl.nasa.gov!usc!samsung!umich!vela!schemers
From: schemers@vela.acs.oakland.edu (Roland Schemers III)
Newsgroups: comp.object
Subject: Re: Examples of Multiple Inheritance?
Summary: C++ Network Objects
Message-ID: <4128@vela.acs.oakland.edu>
Date: 5 Dec 90 21:28:30 GMT
References: <60700005@inmet>
Reply-To: schemers@vela.acs.oakland.edu (Roland Schemers III)
Organization: Oakland University, Rochester MI
Lines: 35

In article <60700005@inmet> stt@inmet.inmet.com writes:
>We are looking for an example of a C++ class (or Eiffel, Objective C,
>etc.) which is a "true" sub-class of two (or more) parent classes;
>that is, it bears the "is-a" relationship to multiple parents.
>

I have written some C++ classes that use MI extensively. The library
is called Transport, and stands for Network Transport. Simply put, a
Transport is something that lets you send data from place to another.

Here is the layout of the classes:

class Transport;
class Socket inherit from Transport;
class UnixSocket inherit from Socket;
class InetSocket inherit Socket;
class DECnetSocket inherit from Socket;
class TransportStream inherit from Transport;
class SocketStream inherit from Socket and TransportStream;
class UnixStream inherit from UnixSocket, and SocketStream;
class InetStream inherit from InetSocket, and SocketStream;
class DECnetStream inherit from DECnetSocket and SocketStream;
class TransportDatagram inherit from Transport;
class SocketDatagram inherit from  Socket, and TransportDatagram;
class InetDatagram inherit from InetSocket and SocketDatagram;

So a InetStream object is a Transport, Socket, InetSocket, TransportStream,
SocketStream, and InetStream object!

Roland
-- 
Roland J. Schemers III                              Systems/Network Manager
schemers@vela.acs.oakland.edu (Ultrix)              Oakland University 
schemers@argo.acs.oakland.edu (VMS)                 Rochester, MI 48309-4401
~Disclaimer::Disclaimer() { reboot(RB_HALT); }      (313)-370-4323