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From: Paul Kenneth Egell-Johnsen <paulken4@afrodite.hibu.no>
Subject: Re: C++ Class
Date: 1997/02/12
Message-ID: <3301DF22.7C0D@afrodite.hibu.no>#1/1
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Date: 1997-02-12T00:00:00+00:00
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Loc Minh Phan Van wrote:

> Hi,
>         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.
> 
>         If so please give me a little example.

That would be an abstract base class, with pure virtual members.

class base
{
	virtual method() = 0; // this is not defined in the base,
                              // derived objects must define this.
                              // Don't think a user can instanciate
                              // this, take a look in the faq.
}

Paul K Egell-Johnsen

mailto:paulken4@afrodite.hibu.no
http://afrodite.hibu.no:8001/paulken4/