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=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,e5eb8ca5dcea2827 X-Google-Attributes: gid103376,public From: Ehud Lamm Subject: Re: Ada OO Mechanism Date: 1999/05/29 Message-ID: #1/1 X-Deja-AN: 483424426 References: <7i05aq$rgl$1@news.orbitworld.net> <7i17gj$1u1k@news2.newsguy.com> <7icgkg$k4q$1@nnrp1.deja.com> <3749E9EC.2842436A@aasaa.ofe.org> <7id2eo$fag@drn.newsguy.com> <3749FF7D.F17CE16A@aasaa.ofe.org> <374AC676.F7AE0772@lmco.com> <374F1DD3.64070C3E@mitre.org> Content-Type: TEXT/PLAIN; charset=US-ASCII Organization: The hebrew University of Jerusalem Mime-Version: 1.0 Newsgroups: comp.lang.ada Date: 1999-05-29T00:00:00+00:00 List-Id: About double dispatching using class-wide paramters and run typme type identifaction using 'tag: I had a feeling this is what you are thinking about, since Ada like the other languages I am familiar with doesn't go for double dispatching - nad rightly so (try to define consistent semantics for such a thing). However using 'tag or other methods of RTTI (as are avaible in C++) is usually concidred un-OOP, and not totally without reason. The argument is that if you do manual checks for tags, you must change the code base when you inherit, as opposed to simply coding new and sperate routines for the overridden and new features of the new type. This is one of the problems OOP tries to solve (you can see this discussed in many OOP books). Some OOP gurus even take the extreme view that almost any if/case statements in a program indicate that the inheritance tree should be exapnded. Ehud Lamm mslamm@pluto.mscc.huji.ac.il