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From: Gregor Kiczales <Gregor@parc.xerox.com>
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In-reply-to: <199711121920.OAA29392@stockberg.ccs.neu.edu> (message from Karl
	Lieberherr on Wed, 12 Nov 1997 11:20:35 PST)
Subject: Re: Be careful what we call an object
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Date: Wed, 12 Nov 1997 12:12:59 PST
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   From: Karl Lieberherr <lieber@ccs.neu.edu>
   Date: Wed, 12 Nov 1997 11:20:35 PST

   We have classes at two levels: ClassDef and CoordinatorDef are 
   at level 1, Point is at level 2. Since CoordinatorDef-objects are 
   instances of a level 1 class and Point-objects are instances of a 
   level 2 class we should not call them both objects without 
   qualification. We could say that coordinators are level-1-objects
   and points are level-2-objects. But it is better to 
   call coordinators just coordinators and not refer to their
   object representation.

I think we can talk about these levels even more clearly using the the
metaobject/metaclass terminology.  So, the picture I would draw is:


       the metaclass                  the metaclass
        named class                 named coordinator
             |                             |
             |                             |
     the metaobject for             the metaobject for
  the class named position         the <foo> coordinator
             |                             |
             |                             |
       a particular                 /  this space   \
       position p1                 <  intentionally  >
                                    \  left blank   /


The key point being that there isn't really a reified object that sits
in the intentionally blank space.