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From: mat@mole-end.UUCP (Mark A Terribile)
Newsgroups: comp.lang.c++
Subject: Re: Bug in multiple inheritence
Summary: Slicing: good for bread ...
Message-ID: <475@mole-end.UUCP>
Date: 3 Feb 91 06:55:45 GMT
References: <1991Jan17.190452.5204@lia> <472@mole-end.UUCP> <70223@microsoft.UUCP>
Organization: mole-end--private system.  admin: mole-end!newtnews
Lines: 23

> |It is also noted in the commentary that this `slicing' may seem dangerous,
> |but that it is consistant with all the other rules of the language, and that
> |protections against probably would give a false confidence.
 
> Compiler writers would do well to issue a warning when "slicing" is 
> performed on objects with virtual functions.  It *could be* that this
> slicing is want the programmer wants.  But the probability would seem
> to be vanishingly small.

I'm not so sure about that.  One of the things I'm trying to come to grips
with right now (actually, trying to write an essay on) is how classes that
play different parts, that have different sorts of roles, can expect to use
inheritance and virtualization differently, if at all.  Certainly, some of
the common examples (GUIs) used by those who teach Object Orientation can
stand slicing.  Many real-world problems cannot.  But probably some can.

Before we make such proclamations, I think we need to develop a set of
concepts to describe the purposes to which are put inheritance and
virtualization.
-- 

 (This man's opinions are his own.)
 From mole-end				Mark Terribile