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_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,f948976d12c7ee33 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2003-07-03 09:58:33 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!newsfeed-east.nntpserver.com!nntpserver.com!chi1.webusenet.com!news.webusenet.com!snoopy.risq.qc.ca!nf3.bellglobal.com!nf1.bellglobal.com!nf2.bellglobal.com!news20.bellglobal.com.POSTED!not-for-mail From: "Warren W. Gay VE3WWG" User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: Boeing and Dreamliner References: <3EFC6FC2.B96DAEA4@adaworks.com> <1056731513.272294@master.nyc.kbcfp.com> <3EFF2F6D.3793971@adaworks.com> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Message-ID: Date: Thu, 03 Jul 2003 12:43:24 -0400 NNTP-Posting-Host: 198.96.223.163 X-Complaints-To: abuse@sympatico.ca X-Trace: news20.bellglobal.com 1057250604 198.96.223.163 (Thu, 03 Jul 2003 12:43:24 EDT) NNTP-Posting-Date: Thu, 03 Jul 2003 12:43:24 EDT Organization: Bell Sympatico Xref: archiver1.google.com comp.lang.ada:40029 Date: 2003-07-03T12:43:24-04:00 List-Id: Alexander Kopilovitch wrote: > Hyman Rosen wrote: >>Richard Riehle wrote: >> >>>And those issues directly support the folly of even thinking about using >>>C++ for this aircraft. >> >>Unsurprisingly, I disagree. You're talking about a situation where every >>arithmetic operation in the code was carefully scrutinized. I'm sure that >>in the cases were protection was left in the Ariane 4 code it did not >>consist of allowing an Ada exception to be raised on overflow, but rather >>coding in such a way that a correct numeric result would be produced. I >>don't see why such scrutiny would not result in equally safe C++ code. > > There is vague but powerful thing - "expectations". In Ada world it is > natural to expect that a component is suited and perhaps optimized for the > particular purpose, unless otherwise it explicitly stated. The situation in > C++ world is often quite opposite: it is common to expect that a class or > class library provides some kind of acceptable/reasonable behaviour for some > generic range of applications, and that behaviour must be overridden if/when > we have have specific requirements. What you're suggesting is that C++ code is always/mostly suitable in a general way. This is like suggesting that an engine made for a Piper cub should always be suitable for bigger jobs like bombers! I think this argument leaks in a major way! ;-) Even what you'd call generic or general solution has limitations. Whether an int or a short is used, you have range limitations. Whether you use a float or a double, you have precision and range limitations builtin. And this is just the tip of the iceburg. C++ does not hold any advantage here. -- Warren W. Gay VE3WWG http://home.cogeco.ca/~ve3wwg