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=0.6 required=5.0 tests=BAYES_00,FROM_WORDY autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,9ab76c2183ecc054 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-01-03 06:00:25 PST Path: supernews.google.com!sn-xit-02!supernews.com!newsfeed.direct.ca!look.ca!cyclone-sjo1.usenetserver.com!news-out.usenetserver.com!nntp.flash.net!news.flash.net!not-for-mail From: "Ken Garlington" Newsgroups: comp.lang.ada References: <92fk1v0cou@drn.newsguy.com> <92fqlt$h8d$1@nnrp1.deja.com> <3A4CF58B.A8FF223C@collins.rockwell.com> <92qfj7$7l9$1@nnrp1.deja.com> <3A5218FB.41FDD@collins.rockwell.com> <3A531C4D.7AB64631@acm.org> Subject: Re: Ada to C Translator 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 Message-ID: Date: Wed, 03 Jan 2001 14:00:11 GMT NNTP-Posting-Host: 216.215.73.122 X-Complaints-To: abuse@flash.net X-Trace: news.flash.net 978530411 216.215.73.122 (Wed, 03 Jan 2001 08:00:11 CST) NNTP-Posting-Date: Wed, 03 Jan 2001 08:00:11 CST Organization: FlashNet Communications, http://www.flash.net Xref: supernews.google.com comp.lang.ada:3609 Date: 2001-01-03T14:00:11+00:00 List-Id: Your mentioning the F119 raises a question in my mind that I probably should have asked a long time ago. IIRC, the Pratt & Whitney gang used Pictures to Code extensively for the engine control. Did the advantages you describe below (easy to read, etc.) really matter in that case, given that Ada essentially became an intermediate language? Now that the rest of the world seems to be catching on to this idea (automatic code generation from UML, etc.), I wonder if that trend is going to make other attributes of text-based languages more important - portability, availability and robustness of associated compilers, etc. No one extols the readability of J-code, do they? "Marin David Condic" wrote in message news:3A531C4D.7AB64631@acm.org... : Speaking as someone who has worked on projects with a similarly long or : longer lifecycle, I'll throw this in: Nobody has a crystal ball with enough : magnifying power to see that far ahead. Example: The F119 engine for the : Advanced Tactical Fighter was in various stages of development for over ten : years before it went into production. In that ten years, the engine control : went from running 68000 processors to 68040 processors (with stops in : between). Before it got to production, Motorola decided that they weren't : going to make a Mil packaged version of the chip anymore no matter how much : whining and snivveling we did. The box will ultimately go into production : using PowerPC chips. The project had frozen a version of the XD-Ada compiler : for a long time and kept VAX/VMS systems around to run it on in spite of : everyone else at the company going to Sun/Unix platforms. Eventually the : project was forced to move on to the Aonix Ada95 compiler for the PowerPC : chip. All that meant major rewriting of the system level software and : reverification of the control. No small task. : : Since projects like this can't possibly forsee what will happen 20 years : from now (new charged particle phased plasma fluidic computational devices? : or maybe total economic colapse followed by a meteor impact that throws us : all back to the stone age?) the powers that be on the project have to have a : plan to deal with the inevitable changes. If you were to, for example, pick : Ada as your programming language and Linux as your OS, what you would want : to do is design the software to isolate machine/OS specific features so they : could easily be replaced and develop your software so that it is clear, : easily understood and readily translated if that need should arise. Ada : shines in these areas for lots of reasons such as readily understood syntax, : modular construction, etc. Ada was designed specifically to support large : projects with a long lifespan. If you write it in Ada, at least your : grandson can come along 20..30 years from now and maybe understand what you : did and translate it into C** or F# or whatever is the new, hip computer : language at that time. (Personally, I'm predicting a resurgence in the use : of Jovial. :-) : : What was it they said in The Mythical Man-Month? When you develop software, : plan to write it twice because you will anyway. : : MDC : : Dave Ptacek wrote: : : > I would be interested in some suggestions as to what languages and : > toolsets would be viable alternatives for maintaining a program 15 - 20 : > years into the future. Please try to take the Ada hat off before you : > respond, it still might be your choice, attempt to rationalize it with : > reasonable statements, consider the logistical situation noted above and : > lastly this is not a "deep pocket" program so funds are limited. : : -- : ====================================================================== : Marin David Condic - Quadrus Corporation - http://www.quadruscorp.com/ : Send Replies To: m c o n d i c @ q u a d r u s c o r p . c o m : Visit my web site at: http://www.mcondic.com/ : : "Giving money and power to Government is like giving whiskey : and car keys to teenage boys." : : -- P. J. O'Rourke : ====================================================================== : :