Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!cs.utexas.edu!sun-barr!newstop!sun!red-dwarf!pallas
From: pallas@red-dwarf.Sun.COM (Joseph Pallas)
Newsgroups: comp.object
Subject: Re: Runtime Class Creation (was: the need for classes as objects)
Keywords: Dynamic class creation, dynamic linking, ROTTETANG.
Message-ID: <141522@sun.Eng.Sun.COM>
Date: 29 Aug 90 18:26:24 GMT
References: <2259@esquire.UUCP> <9959@goofy.Apple.COM> <1990Aug29.025227.19172@Neon.Stanford.EDU>
Sender: news@sun.Eng.Sun.COM
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In <1990Aug29.025227.19172@Neon.Stanford.EDU> agesen@Neon.Stanford.EDU
(Ole Agesen) writes:

>Take BETA, a compiled, statically 
>typed language, in which classes are NOT objects. In [PBETA] it is shown 
...
>classes need not be objects in order
>to be constructed at runtime. We need only be able to manipulate descriptions
>of classes at runtime!

So what exactly is the difference between "classes are objects" and
"descriptions of classes are objects"?  Not much that I can see,
except that in Smalltalk the form of the objects-that-describe-classes
is dictated by the system.

>All this, however, still leaves the original question unanswered:
>"WHY SHOULD CLASSES BE OBJECTS?" I would also like to know!

Why not?  Object-oriented programming languages have the manipulation
of objects as their foundation.  So, if you want to manipulate
classes, make them objects.

joe

P.S.  Is there any easy way to get hold of a copy of this?
>"Persistent and Shared Objects In BETA"; O. Agesen, S. Froelund, M. H. Olsen;
>Masters thesis, Daimi IR-89; April 1989, Computer Science Department, Aarhus
>University, Denmark.   -- In the thesis concepts related to dynamic class
>construction are discussed. It is shown how dynamic class construction can 
>yield a sound basis for the design of persistent objects.