Xref: utzoo comp.lang.eiffel:1395 comp.object:2537
Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!olivea!uunet!hsi!hsi86!wright
From: wright@hsi86.hsi.com (Gary Wright)
Newsgroups: comp.lang.eiffel,comp.object
Subject: Re: Inheritance and Information Hiding
Message-ID: <3038@hsi86.hsi.com>
Date: 8 Feb 91 16:02:41 GMT
References: <808@puck.mrcu> <10612@pasteur.Berkeley.EDU> <1080@tetrauk.UUCP> <27A9AB0C.4794@tct.uucp>
Reply-To: wright@hsi.com (Gary Wright)
Followup-To: comp.lang.eiffel
Organization: 3M Health Information Systems, Wallingford, CT
Lines: 14

In article <27A9AB0C.4794@tct.uucp> chip@tct.uucp (Chip Salzenberg) writes:
>Inheritance and information hiding issues are orthagonal to assertion
>issues.  A given language may support the former, the latter, both, or
>neither.  Let's keep the discussions clear.

At least in Eiffel, the semantics of inheritance are not orthagonal
to assertions.  An interesting part of this discussion has been what
role assertions (pre-conditions, post-conditions, invariants) have in
an inheritance model and how does that restrict the way a class can
be changed with respect to its parent(s).  I'd like to hear more, not
less, regarding this issue.
-- 
Gary Wright                                                 ...!uunet!hsi!wright
3M Health Information Systems					  wright@hsi.com