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Fwd: Re: OO inheritance in a hacker style

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From:
Joseph Ryan
Date:
February 4, 2004 14:21
Subject:
Fwd: Re: OO inheritance in a hacker style
Message ID:
40216B78.9000900@osu.edu
Woops, sent it to the wrong list!

- Joe

Joseph Ryan wrote:

>  Luke Palmer wrote:
>
>> Austin Hastings writes:
>>  
>>
>>>> Hmm. The text and examples so far have been about methods and this
>>>> seems to be about multi-methods.  Correct me if I'm wrong ...
>>>>     
>>>
>>> You're wrong. Consider my example, where via single inheritance we 
>>> reach a
>>> "layered" list of methods, each of which replaces the previous one 
>>> in the
>>> namespace (parent.method superseded by child.method). This is not
>>> multi-dispatch -- the class of the object being dispatched 
>>> determines the
>>> method -- but I want to modify the dispatch chain so that some upstream
>>> class' method is "ignored".
>>>   
>>
>>
>> It's surely possible by modifying that class's DISPATCH. 
>> Whether it should actually be in the language is up for debate.  I'd say
>> that if you need to do this with any frequency whatsoever, you're not
>> thinking about roles right.  A good example might be in order... :-)
>>  
>>
>
> Well, what if the two classes you want to inherit from weren't
> designed with roles in mind?  For instance, there might be two
> CPAN modules that each have a dozen methods that you want to
> inherit, but they each have 1 that overlap whose conflict you
> want to easily resolve.
>
> Besides, "the user is not thinking about XXX right" sounds like we
> need to give a ++ to the pythonometer ;)
>
> - Joe
>


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