* * * * *
                                        
                              The Platypus Effect.
                                        
> “You have your `isa' hierarchy all thought out - let's say you have a
> “mammals” class and a “reptiles” class and so on - and you start to
> implement it, and along comes a platypus, a fur-bearing, egg-laying, duck-
> billed creature, which doesn't appear to fit in any of the classifications
> you've created. So what you often end up having to do is rethink your
> entire hierarchy, refactoring into a different set of basic categories, or
> maintaining several categorizations along different axes. A lot of your
> thinking ends up getting thrown out, as well as any implementation you've
> done up to that point.”
> 

Via RobotWisdom, [1] Encapsulation, Inheritance and the Platypus effect. [2]

[1] http://www.robotwisdom.com/
[2] http://www.advogato.org/article/83.html

Email Sean Conner at sean@conman.org

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