Re: Retrofitting base class with pure virtual function

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From: Joseph M. Newcomer (newcomer_at_flounder.com)
Date: 04/10/04 

Date: Sat, 10 Apr 2004 13:58:14 -0400

You can't. If you introduce a pure virtual method, every derived class must implement the
virtual method. If they do not, then you can't implement a pure virtual method (you might
consider implementing a method that does ASSERT(FALSE), but if you add a new pure virtual
method, every derived class will have to be modified to implement a real version of the
method). That's just how C++ works.
                                joe

On Wed, 7 Apr 2004 17:56:55 -0400, "Ken->" <handsom@comcast.netspicedham> wrote:

>I have a base class that is inherited by several classes and they all have
>there own ReadFile and WriteFile functions. The base class does not have a
>ReadFile or WriteFile, but can I now add a pure virtual ReadFile and
>WriteFile function to the base class without screwing up the classes that
>already inherit from it?
>

Joseph M. Newcomer [MVP]
email: newcomer@flounder.com
Web: http://www.flounder.com
MVP Tips: http://www.flounder.com/mvp_tips.htm

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