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From: Mark Wilden <Mark@mwilden.com>
Subject: Re: Q: virtual functions not overridable anymore?
Date: 1997/09/11
Message-ID: <34172B24.38DE@mWilden.com>#1/1
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Cristian Georgescu wrote:
> 
> Suppose you have a class Apple with a virtual function getColor(); then I
> want to make a derived class GreenApple with getColor that will always
> return Green.

Since this would (probably) be a bad class design in the first place,
maybe there's a better example?

I can't think of a good use for GreenApple that couldn't better be
served simply by

 struct Apple {
    enum Color { Green, Red };
    Apple(Color, double price);
    Color getColor() const;
    double getPrice() const;
 private:
    const Color color;
    const double price;
 };

Classes should reflect behavior, not attributes--if only to avoid a
combinatorial explosion of subclasses from the union of all possible
attribute values.

I think a better example would make your point clearer.
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