Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!microsoft!ilanc
From: ilanc@microsoft.UUCP (Ilan CARON)
Newsgroups: comp.lang.c++
Subject: Re: Multiple Inheritance Problem
Message-ID: <72341@microsoft.UUCP>
Date: 14 May 91 15:38:53 GMT
References: <74462@brunix.UUCP> <2153@godzilla.tcs.com>
Reply-To: ilanc@microsoft.UUCP (Ilan CARON)
Organization: Microsoft Corp., Redmond WA
Lines: 17

In article <2153@godzilla.tcs.com> robert@kohlrabi.tcs.com (Robert Blumen) writes:

>For one thing, a class that inherits a pure virtual function must define it
>or redefine it to be pure virtual.
>

Actually this is no longer the case -- as of the ARM (p. 215), a pure
virtual function is in fact inherited as a pure virtual.  I.e. you 
don't need to redeclare it explicitly (if you're not defining
it in the derived class).  However, I believe this is only implemented
in 2.1 conformant compilers.

[This is a good design decision since otherwise "demoting" a pure
virtual to an "impure" virtual in a base class would require mucking
with all derived classes].

--ilan caron (uunet!microsoft!ilanc)