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From: ddean@rain.andrew.cmu.edu (Drew Dean)
Newsgroups: comp.object
Subject: Re: Void references
Summary: A question
Message-ID: <11113@pt.cs.cmu.edu>
Date: 15 Nov 90 16:22:19 GMT
References: <MOSS.90Nov14094958@ibis.cs.umass.edu> <454@eiffel.UUCP> <1990Nov15.011702.25087@Neon.Stanford.EDU>
Organization: Carnegie Mellon University
Lines: 9

From a relative neophyte, if a subclass only inherits parts of its superclass
(ie. some subset of the methods and/or variables), how can an instance
of the subclass be used anywhere an instance of the superclass can be used ?
In my (comparably primitive) understanding of OOP, this is important.  Without
this property, what good are abstract classes, which seem to be a useful 
organizational tool ?

Drew Dean
Drew_Dean@rain.andrew.cmu.edu