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=-0.4 required=5.0 tests=AC_FROM_MANY_DOTS,BAYES_00 autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,6d10b4841e4a643b X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2002-04-15 17:20:58 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news.tele.dk!small.news.tele.dk!194.42.224.136!diablo.netcom.net.uk!netcom.net.uk!easynet-monga!easynet-melon!easynet.net!psiuk-p2!psiuk-p3!uknet!psiuk-n!news.pace.co.uk!nh.pace.co.uk!not-for-mail From: "Marin David Condic" Newsgroups: comp.lang.ada Subject: Re: Are rendezvous dead? Date: Mon, 15 Apr 2002 09:38:52 -0400 Organization: Posted on a server owned by Pace Micro Technology plc Message-ID: References: <3CB940F7.4EC50CFD@yahoo.com> NNTP-Posting-Host: dhcp-200-133.miami.pace.co.uk X-Trace: nh.pace.co.uk 1018877933 4731 136.170.200.133 (15 Apr 2002 13:38:53 GMT) X-Complaints-To: newsmaster@news.cam.pace.co.uk NNTP-Posting-Date: 15 Apr 2002 13:38:53 GMT X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Xref: archiver1.google.com comp.lang.ada:22573 Date: 2002-04-15T13:38:53+00:00 List-Id: "Pat Rogers" wrote in message news:sYfu8.157$h24.105729203@newssvr11.news.prodigy.com... > > > If tasks require _direct_ communication/synchronization, rendezvous is generally > the right way to go for that specific part of their behavior. Otherwise, > protected objects are preferable. > > There are a variety of Object Oriented design idioms I've run into recently dealing with Active Objects and how they might communicate with each other. For a number of these idioms the Ada rendesvous is a simple, direct representation that would likely be more efficient than cobbling together the same answer using protected objects (or some other mechanism). For other idioms, the heavy weight of the rendezvous is the proverbial Brick Outhouse and often it is harder to do this way. (e.g. a mailbox where you just want to leave data for another task to process when it gets around to it.) For the lighter-weight communication and synchronization, protected objects are a real blessing & improvement over Ada83. You really want to have both kinds of tools in the toolbox because design needs vary. I'd see the rendezvous and protected types both being available to the designer as a major advantage that Ada has over many other languages. MDC -- Marin David Condic Senior Software Engineer Pace Micro Technology Americas www.pacemicro.com Enabling the digital revolution e-Mail: marin.condic@pacemicro.com