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From: William Ying <william.ying@barra.com>
Subject: Re: C++ Class
Date: 1997/02/12
Message-ID: <33021255.2C7A@barra.com>#1/1
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Date: 1997-02-12T00:00:00+00:00
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Loc Minh Phan Van wrote:
>         Is there anyway that we can Define a class that can not be instantiated
> in any way by the user (that is, you can not have objects of that type),
> but it can be used as a base class.

Two solutions:
1)	Make the base class as Abstract Base Class (or Absolute Base Class in
some books) by setting a virtual function to be zero.  It is well
documented in any C++ books.
2)	Put the base class constructors in protected field.

- Bill -