> I just did a quick glance over the paper and perhaps I'm wrong but I'm
> missing a point about refactoring. Why is this important?! Well, in a 
> large number
> of cases code reuse does not come from the initial design but rather
> somewhere down the road when we see similarities in concepts that 
> really should be
> represented by a common one. Traits seem to be a very nice solution to 
> that
> problem as well since (I think) they have very elegant ways of 
> reifying those
> concepts and make them readily accessible.
>
> BTW, I'm really looking forward to trying the traits out myself. Not 
> that I
> want to put any pressure on you, of course ;-)))

But this is positive pressure ;))))
>
> Cheers,
>   - Andreas
>
>> Tim,
>>
>> I agree with you. Your critics on MI is just about what inspired us to
>> do the Traits work. Have a look at the latest draft of the Traits 
>> paper
>> (http://www.iam.unibe.ch/~schaerli/traits_draft/traitsDraft.pdf) and 
>> you
>> will find a detailed description of good reasons why MI ddidn't make 
>> it
>> into recent languages. I hope that Traits are going to be more
>> successful ;)
>>
>> Nathanael
>>
>>> -----Original Message-----
>>> From: squeak-dev-admin at lists.squeakfoundation.org
>>> [mailto:squeak-dev-admin at lists.squeakfoundation.org] On
>>> Behalf Of Tim Rowledge
>>> Sent: Monday, November 18, 2002 7:38 PM
>>> To: squeak-dev at lists.squeakfoundation.org
>>> Subject: Re: Classes as Packages (was: Harvesting infrastructure)
>>>
>>>
>>>
>>>>> And anyone that starts going on about multiple inheritance is
>>>>> looking for a visit from one of the four horsement of the
>>>>> apologists. :-)
>>>>
>>>> I think this is a myth of multiple inheritance.  I think it can be
>>>> tamed and used effectively.  See above.
>>> Lots of people have tried to convince of that in the last
>>> twenty years and so far not a one has made a good enough case
>>> to change my mind. It is certainly possible you may be the
>>> first but don't hold your breath too long!
>>>
>>> One of the classic old claims for MI was along the lines of -
>>> well, I have implemented Toy and Truck and now I want a toy
>>> truck so I should be able to inherit from both. Yippee, it's
>>> obvious! BZZZZZZ.
>>>
>>> Firstly, like many occasions where people make claims
>>> congurent to this, it's a bad example. Truck, if implemented
>>> in any serious manner, will have a great deal of state and
>>> behaviour that is nothing whatosever to do with toy trucks.
>>> Do toy trucks need to know about, say, service schedules,
>>> fuel consumption, tyre pressure et al.? I doubt it. It's a bad mix.
>>>
>>> Secondly, I've never yet been convinced that any proposed
>>> implementation of MI can handle the tangle of possible
>>> inheritance upstream. Where and how should one decide which
>>> of the possible upward paths to follow? If following one path
>>> leads to a DNU should you try another? And another? I think
>>> it is easy to see a pretty nasty O(something horrible)
>>> problem here. How would one specify which path to use it if
>>> it supposed to be decided by the programmer? The old ST-80 MI
>>> experiment used munged selectors, something like 'self
>>> truck.size' which looked 'orrible. And probably allowed
>>> something like 'self number.wibble' whcih wuldbe nonsensical.
>>>
>>> Thirdly, it always seems more plausible to me to use
>>> composition/delgation. ToyTruck would be a little better if
>>> implemented as having a toy-ness ivar and a truck-ness ivar
>>> and then _using_ them rather than inheriting them. I imagine
>>> that this maps onto Traits reasonably well from my current
>>> understanding. I would concur however that making it possible
>>> to subclass traits would be (probably) useful; but let's not
>>> go into whether traits should have trairts, at least just yet.
>>>
>>> tim
>>> -- 
>>> Tim Rowledge, tim at sumeru.stanford.edu,
>>> http://sumeru.stanford.edu/tim Useful > random insult:- He
>>> donated his brain to science but they made an early withdrawal.
>>>
>>>
>>
>>
>
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>
>
Dr. Stéphane DUCASSE (ducasse at iam.unibe.ch) 
http://www.iam.unibe.ch/~ducasse/
  "if you knew today was your last day on earth, what would you do
  different? ... especially if, by doing something different, today
  might not be your last day on earth" Calvin&Hobbes