Re: C++ hierarchy problem

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From: Telesis North
Date: Mon, 07 Aug 1995 17:06

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In article <3vqr6h$8nj@imag.imag.fr>,
Gilles Serasset  <Gilles.Serasset@imag.fr> wrote:
>I face a problem related to C++ classes. And I would like to know how to
>get rid of it.
>
>void A2::DoThis(void) { ((B2 *)(this->bb))->DoThat(); }
>
>B3 inherits from B2 and redefines DoThat().
>A2 is not modified (but its bb slot contains a B3 instance).

If I understand your system correctly, then making B2::DoThat() virtual
ought to give you what you want. (Might as well declare A2::DoThis()
virtual as well, for symmetry if nothing else.)

cheers,

Roger Pantos                 Telesis North, Inc.           telesisnorth
Mac Software Guy             telesis@ecf.toronto.edu       (AppleLink)
I've got a Mac instead of a DOS box because I need a tool, not a hobby.

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Newsgroups: comp.sys.mac.programmer.codewarrior,comp.sys.mac.oop.misc,comp.lang.c++
Path: arc1-ca.pugleaf.net!cannon.ecf!telesis
From: telesis@ecf.toronto.edu (Telesis North)
Subject: Re: C++ hierarchy problem
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Date: Mon, 7 Aug 1995 17:06:16 GMT

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