From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: * X-Spam-Status: No, score=1.9 required=5.0 tests=BAYES_50,INVALID_DATE, MSGID_SHORT autolearn=no autolearn_force=no version=3.4.4 Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!gem.mps.ohio-state.edu!uakari.primate.wisc.edu!aplcen!haven!h.cs.wvu.wvnet.edu!eichmann@h.cs.wvu.wvnet.edu From: eichmann@h.cs.wvu.wvnet.edu (David A Eichmann,316K) Newsgroups: comp.lang.ada Subject: Re: Does Ada really need MULTIPLE inheritance? Message-ID: <503@h.cs.wvu.wvnet.edu> Date: 17 Oct 89 17:23:53 GMT References: <8910161521.AA27039@ajpo.sei.cmu.edu> Sender: news@h.cs.wvu.wvnet.edu List-Id: >From article <8910161521.AA27039@ajpo.sei.cmu.edu>, by NCOHEN@IBM.COM ("Norman H. Cohen"): ... > Since nobody at either workshop was a strenuous advocate of multiple > inheritance, I would like to see the argument for multiple inheritance OK, let's say I'm creating refinements of a general concept of vehicle, which contains two attributes, means of propulsion(motor, air, etc.) and operating medium(land, air, water). I can make an initial refinement of air vehicles (adding appropriate attributes), land vehicles, and water vehicles - refining by medium; or I can refine to motor vehicles, air (powered) vehicles, etc - refining by propulsion. With single inheritance, I must choose one over the other. With multiple inheritance, there is no need. A motorized air vehicle is an instance of both air vehicle AND an instance of motorized vehicle. My initial design choice is not coloring subsequent interpretations and perspectives on the objects in question. ----- David Eichmann Dept. of Statistics and Computer Science West Virginia University Phone: (304) 293-3607 Morgantown, WV 26506 Email: eichmann@a.cs.wvu.wvnet.edu