Path: utzoo!attcan!uunet!mcvax!ukc!warwick!rlvd!cmc
From: cmc@inf.rl.ac.uk (Chris Crampton)
Newsgroups: comp.lang.c++
Subject: Re: C++ multiple inheritance (really virtual)
Message-ID: <3167@rlvd.UUCP>
Date: 11 Jul 88 14:48:13 GMT
Reply-To: cmc@inf.rl.ac.uk (Chris Crampton)
Organization: Rutherford Appleton Laboratory, Didcot. UK.
Lines: 22

In article <401@otc.oz> mikem@otc.oz (Mike Mowbray) writes:
>...
>This would tend to imply that future library designers should always use
>virtual bases unless they have a very good reason not to.

Indeed, if a library is to be truly extensible then it seems to me that
the designers should make all methods and destructors virtual unless they
have a good reason not to. Another tough decision for library designers
is which methods (and possibly data) should be made protected instead of
private. Bad decisions made early on can make things very difficult for
programmers who are sub-classing rather than just using the existing
classes. 

I sometimes wish that virtual were the default...

Chris.

=======================================================================
Chris M Crampton		UK JANET:   cmc@uk.ac.rl.inf
Rutherford Appleton Labs,	ARPA:	    cmc%inf.rl.ac.uk@nss.cs.ucl.ac.uk
Didcot, OXON, U.K.		UUCP:	    ..!mcvax!ukc!rlvd!cmc
+44 235 21900   ext. 6756		    cmc@rlvd.uucp