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From: bpe@brunix (Page Elmore)
Newsgroups: comp.lang.c++,comp.lang.eiffel,comp.lang.smalltalk
Subject: Re: Use of inheritance for classification?
Message-ID: <6743@brunix.UUCP>
Date: 18 May 89 14:41:16 GMT
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Reply-To: bpe@zaphod.UUCP (Page Elmore)
Organization: Brown University Department of Computer Science
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I agree with Bob Heiney's comments -- we are confusing matters by mixing
subsets with subtypes via inheritance. I would say that we need a mechanism
for is-a inheritance which preserves substitutability, and one for subset
which allows classifiction.

Page Elmore
Object-Oriented Database Programming Language Project
Brown University Computer Science Department