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From: shang@corp.mot.com (David L. Shang)
Subject: Re: Types, types: static vs. dynamic -- classification
Reply-To: shang@corp.mot.com
Organization: MOTOROLA 
Date: Wed, 29 Nov 1995 16:59:38 GMT
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In article <yf391l0mjqn.fsf@sabi.demon.co.uk> piercarl@sabi.demon.co.uk  
(Piercarlo Grandi) writes:
> >>> On Tue, 28 Nov 1995 14:55:08 GMT, shang@corp.mot.com (David L. Shang)  
said:
> 
> David> How does an object change its type dynamically? Shouldn't we
> David> consider the object a different object when its type is changed?
> 
> pcg> It is actually an interesting question, and one whose answer is not
> pcg> so obvious, also because metamorphism or dynamic retyping is not
> pcg> well known ot studied. [ ... more musings on versioning ... ]
> 
> David> When a class (type) is modified, it is still this class (type).
> David> We should not consider it is a different class (type).
> 
> Oh no. You mean that if I have a class/type 'pair' that describes
> objects with fields '(pair,pair)' with operations 'cons,car,cdr', and
> then I change it in place so that it describes objects with fields
> 'real,imaginary' and operations '+,-,*,/' then it's still the same type
> because the name has not changed?
> 
> David> When my age increases by one, I'm still myself.  When I leaned a
> David> new skill, I'm still myself, not someone else.
> 
> Oh no, oh no. Another entry for inanity of the year. Do you realize that
> these are deep, difficult philosophical questions, and that your facile
> answers are pitifully inadequate and unsupported by anything resembling
> an argument.
> 
> Should I quote some ancient greek geek as 'you never swim in the same
> river' for a different opinion? And that regardless of this, the issue
> of what is 'you' is totally unrelated to what is/should be a 'type', and
> therefore any such analogy is fallacious and/or misleading.

Yes, I know this is a deep, difficult philosophical question that no
body can provide a proper answer.

Sorry for many misunderstandings. The purpose of my original question
is try to deny the idea to define how an object change its type, but
I myself was aslo misled by the blind struggle in the trapping question.

No debate. Period.

David Shang


