From: Derek Clarke <derek.clarke@gecm.com>
Subject: Re: Papers on the Ariane-5 crash and Design by Contract
Date: 1997/04/04
Date: 1997-04-04T00:00:00+00:00 [thread overview]
Message-ID: <5i3fmr$cgn@gcsin3.geccs.gecm.com> (raw)
In-Reply-To: 01bc4021$607eea80$b280400a@gavinspc
"Gavin Collings" <gcollings@sperry-sun.com> wrote:
>--
>Joachim Durchholz <joachim.durchholz@munich.netsurf.de> wrote > The class
>EXCEPTION with several subclasses does exist as part of the
>> standard libraries. Exception handlers can decide what to do based on the
>
>> run-time class of the exception. This facility does not seem to be in
>> wide-spread use, but it's all there.
>
>Good. The main point about the Java model, though, is that the compiler
>checks that the programmer has at least thought about handling all
>exceptions that may be generated in nested calls. This means that the
>programmer HAS to think about dealing with error conditions. So, in the
>Ariane case, if the precondition existed (as some say it did) the compiler
>would have given warnings to the effect that it IF the error occurred, it
>would NOT have been handled. Wouldn't this have made the disaster less
>likely?
No, no and thrice no!
The Ariane 4 software people _knew_ about this possibility. They made the
judgement call that this particular floating-point to integer conversion
would never exceed the integer range and cause an exception because the
velocity reading that produced the floating-point value would never
exceed the danger value in the real (Ariane 4) environment.
Whether or not you agree with leaving exceptions unhandled on efficiency
grounds, that was a genuine engineering decision in the light of all
available evidence.
Some long time following this judgement call, which was carefully
documented , passed by several committees, and generally inspected to
death, someone in the _management_ structure of the _Ariane 5_ project
decided not to test the assumptions built into the unit concerned by
denying the technical team for Ariane 5 access to data of the projected
flight profile for the new launcher.
No number of language features would get around this dumbass move.
next prev parent reply other threads:[~1997-04-04 0:00 UTC|newest]
Thread overview: 254+ messages / expand[flat|nested] mbox.gz Atom feed top
1997-03-15 0:00 Papers on the Ariane-5 crash and Design by Contract Bertrand Meyer
1997-03-18 0:00 ` Ariane-5: can you clarify? (Re: Please do not start a language war) Jon S Anthony
1997-03-19 0:00 ` Papers on the Ariane-5 crash and Design by Contract Chris Brand
[not found] ` <tz8ohcjv7cc.fsf@aimnet.com>
1997-03-16 0:00 ` Robert Dewar
1997-03-17 0:00 ` Please do not start a language war (was " Jean-Marc Jezequel
[not found] ` <tz8913l930b.fsf_-_@aimnet.com>
1997-03-18 0:00 ` Ariane-5: can you clarify? (Re: Please do not start a language war) Gavin Collings
1997-03-18 0:00 ` Ariane-5: can you clarify? (Re: Please do not start a language war Roedy Green
1997-03-18 0:00 ` Please do not start a language war (was Re: Papers on the Ariane-5 crash and Design by Contract Ken Garlington
[not found] ` <199703190839.JAA02652@stormbringer.irisa.fr>
1997-03-19 0:00 ` Ken Garlington
1997-03-20 0:00 ` Robert S. White
1997-03-20 0:00 ` Martin Tom Brown
1997-03-21 0:00 ` Robert S. White
1997-03-21 0:00 ` Wolfgang Gellerich
1997-03-20 0:00 ` John L. Ahrens
1997-03-20 0:00 ` Roger T.
1997-03-21 0:00 ` Jean-Marc Jezequel
1997-03-24 0:00 ` Ken Garlington
1997-03-21 0:00 ` Ken Garlington
1997-03-19 0:00 ` Jean-Marc Jezequel
1997-03-19 0:00 ` Richard Kaiser
1997-03-21 0:00 ` Ken Garlington
1997-03-21 0:00 ` Jean-Marc Jezequel
1997-03-25 0:00 ` Ken Garlington
1997-03-26 0:00 ` Trust but verify " Robert S. White
1997-03-25 0:00 ` Bertrand Meyer
1997-03-26 0:00 ` Robb Nebbe
1997-03-27 0:00 ` Ken Garlington
1997-03-28 0:00 ` Jeffrey W. Stulin
1997-03-31 0:00 ` Ken Garlington
1997-03-28 0:00 ` Karel Th�nissen
1997-03-28 0:00 ` Ken Garlington
1997-04-07 0:00 ` Jean-Marc Jezequel
1997-03-29 0:00 ` the one and only real true kibo
1997-03-18 0:00 ` Please do not start a language war " Richard Irvine
1997-03-17 0:00 ` John McCabe
[not found] ` <tz8n2s1hrdc.fsf@aimnet.com>
1997-03-20 0:00 ` John McCabe
1997-03-20 0:00 ` John McCabe
1997-03-20 0:00 ` Jean-Marc Jezequel
1997-03-20 0:00 ` John McCabe
1997-03-21 0:00 ` Niall Cooling
1997-03-21 0:00 ` Gavin Collings
1997-03-27 0:00 ` Joachim Durchholz
1997-04-03 0:00 ` Gavin Collings
1997-04-03 0:00 ` Ken Garlington
1997-04-04 0:00 ` Derek Clarke
1997-04-04 0:00 ` Derek Clarke [this message]
1997-04-06 0:00 ` Robert Dewar
1997-04-07 0:00 ` Ken Garlington
1997-04-09 0:00 ` Gavin Collings
1997-04-03 0:00 ` Robert I. Eachus
1997-04-04 0:00 ` Derek Clarke
1997-04-04 0:00 ` Chris Beer
1997-04-04 0:00 ` Ken Garlington
1997-04-04 0:00 ` Robert Dewar
1997-04-03 0:00 ` Robin Rosenberg
1997-03-24 0:00 ` Ken Garlington
1997-03-26 0:00 ` Thomas Beale
1997-03-26 0:00 ` Ken Garlington
1997-03-21 0:00 ` "Paul E. Bennett"
1997-03-22 0:00 ` Nigel Tzeng
1997-03-23 0:00 ` John McCabe
1997-03-17 0:00 ` Paul Johnson
1997-03-17 0:00 ` Enrico Facchin - Sartori E.T.
1997-03-19 0:00 ` Anders Pytte
1997-03-18 0:00 ` Ken Garlington
1997-03-17 0:00 ` Bertrand Meyer
1997-03-18 0:00 ` John McCabe
1997-03-18 0:00 ` Ray McVay
1997-03-27 0:00 ` Robert Dewar
1997-03-29 0:00 ` the one and only real true kibo
1997-03-30 0:00 ` Nick Roberts
1997-04-06 0:00 ` Doctorb
1997-04-08 0:00 ` Ron Crocker
1997-04-11 0:00 ` Richard Riehle
1997-03-17 0:00 ` Nick Leaton
1997-03-17 0:00 ` Richard Kaiser
[not found] ` <tz8g1xtzx9y.fsf@aimnet.com>
1997-03-18 0:00 ` Anders Pytte
1997-03-18 0:00 ` Jean-Marc Jezequel
1997-03-18 0:00 ` Anders Pytte
1997-03-19 0:00 ` Programming language fanaticism! Louis Bastarache
1997-03-20 0:00 ` Anders Pytte
1997-03-20 0:00 ` Papers on the Ariane-5 crash and Design by Contract Matt Kennel (Remove 'nospam' to reply)
1997-03-24 0:00 ` Joachim Durchholz
1997-03-24 0:00 ` Anders Pytte
1997-03-26 0:00 ` Matt Kennel (Remove 'nospam' to reply)
1997-03-29 0:00 ` Anders Pytte
1997-03-29 0:00 ` Steve Furlong
1997-03-26 0:00 ` Robert Dewar
1997-03-27 0:00 ` the one and only real true kibo
1997-03-29 0:00 ` the one and only real true kibo
1997-03-29 0:00 ` Nick S Bensema
1997-03-30 0:00 ` the one and only real true kibo
1997-03-18 0:00 ` Anders Pytte
1997-03-21 0:00 ` Ken Garlington
1997-03-21 0:00 ` Bertrand Meyer
1997-03-21 0:00 ` William Clodius
1997-03-21 0:00 ` Bertrand Meyer
1997-03-23 0:00 ` William Clodius
1997-03-23 0:00 ` the one and only real true kibo
1997-03-22 0:00 ` Fergus Henderson
1997-03-22 0:00 ` Bertrand Meyer
1997-03-23 0:00 ` the one and only real true kibo
1997-03-23 0:00 ` Anders Pytte
1997-03-24 0:00 ` FUD (Re: Papers on the Ariane-5 crash and Design by Contract) Alexander Anderson
1997-03-24 0:00 ` Alexander Anderson
1997-03-23 0:00 ` Papers on the Ariane-5 crash and Design by Contract Anders Pytte
[not found] ` <3335BC24.13728473@eiffel.com>
1997-03-23 0:00 ` Bertrand Meyer
1997-03-24 0:00 ` Robert Dewar
1997-03-31 0:00 ` Ken Garlington
1997-04-01 0:00 ` Bertrand Meyer
1997-03-25 0:00 ` Ken Garlington
1997-03-24 0:00 ` Ken Garlington
1997-03-24 0:00 ` the one and only real true kibo
1997-03-24 0:00 ` Ken Garlington
1997-03-26 0:00 ` Robert Dewar
1997-03-26 0:00 ` Ken Garlington
[not found] ` <E7ox17.MKx@syd.csa.com.au>
1997-03-28 0:00 ` Ken Garlington
1997-03-24 0:00 ` John Hogg
1997-03-18 0:00 ` Laurent Moussault
1997-03-18 0:00 ` Richard Kaiser
1997-03-18 0:00 ` Nick Leaton
1997-03-19 0:00 ` Richard Kaiser
1997-03-19 0:00 ` Fergus Henderson
1997-03-19 0:00 ` Jean-Marc Jezequel
1997-03-19 0:00 ` Richard Kaiser
1997-03-18 0:00 ` Jean-Marc Jezequel
1997-03-19 0:00 ` Ken Garlington
1997-03-18 0:00 ` Richard Kaiser
1997-03-18 0:00 ` Nick Leaton
1997-03-18 0:00 ` "Paul E. Bennett"
1997-03-19 0:00 ` Nick Leaton
1997-03-24 0:00 ` Joachim Durchholz
1997-03-25 0:00 ` Robert Dewar
1997-03-31 0:00 ` Joachim Durchholz
1997-04-02 0:00 ` Robert Dewar
1997-04-03 0:00 ` Martin Tom Brown
1997-04-04 0:00 ` Derek Clarke
1997-04-04 0:00 ` Jonathan Egre'
1997-04-06 0:00 ` Robert Dewar
1997-04-06 0:00 ` Nick Roberts
1997-03-31 0:00 ` Jan Galkowski
1997-03-31 0:00 ` Alexander Anderson
1997-04-01 0:00 ` Alexander Anderson
1997-04-02 0:00 ` Ken Garlington
1997-03-20 0:00 ` John the Hamster
1997-03-17 0:00 ` Alexander Anderson
1997-03-17 0:00 ` Please do not start a language war (was " Jon S Anthony
1997-03-18 0:00 ` Kent Tong
1997-03-20 0:00 ` Ranan Fraer
1997-03-17 0:00 ` Robert I. Eachus
1997-03-17 0:00 ` Martin Tom Brown
1997-03-18 0:00 ` Jon S Anthony
1997-03-19 0:00 ` Ron Forrester
1997-03-21 0:00 ` Ken Garlington
1997-03-22 0:00 ` Ron Forrester
1997-03-18 0:00 ` Jon S Anthony
1997-03-18 0:00 ` Robert I. Eachus
1997-03-18 0:00 ` Jon S Anthony
1997-03-18 0:00 ` Ulrich Windl
1997-03-18 0:00 ` Tarjei Jensen
1997-03-18 0:00 ` Ken Garlington
1997-03-19 0:00 ` Eric M. Boyd
1997-03-19 0:00 ` Jeffrey W. Stulin
[not found] ` <3345cd60.2092398@news.sydney.apana.org.au>
1997-04-03 0:00 ` Ariane-5 crash , Eiffel and Ada Jeffrey W. Stulin
1997-04-03 0:00 ` Nick Leaton
1997-04-08 0:00 ` AdaWorks
1997-03-18 0:00 ` Papers on the Ariane-5 crash and Design by Contract Jon S Anthony
1997-03-19 0:00 ` Karel Th�nissen
1997-03-19 0:00 ` Ariane-5: can you clarify? (Re: Please do not start a language war) Karel Th�nissen
1997-03-19 0:00 ` Papers on the Ariane-5 crash and Design by Contract Jon S Anthony
1997-03-20 0:00 ` Jean-Marc Jezequel
1997-03-24 0:00 ` Ken Garlington
1997-03-20 0:00 ` Paul Johnson
1997-03-24 0:00 ` Ken Garlington
1997-03-24 0:00 ` Design by Contract in C++ (was Re: Papers on the Ariane-5 crash and Design by Contract) Anders Pytte
1997-03-19 0:00 ` Papers on the Ariane-5 crash and Design by Contract Nick Leaton
1997-03-19 0:00 ` Karel Th�nissen
1997-03-19 0:00 ` Jon S Anthony
1997-03-19 0:00 ` Ken Garlington
1997-03-19 0:00 ` Ken Garlington
1997-03-20 0:00 ` Richard Kaiser
1997-03-24 0:00 ` Ken Garlington
1997-03-20 0:00 ` Martin Tom Brown
1997-03-21 0:00 ` Frank Manning
1997-03-21 0:00 ` Martin Tom Brown
1997-03-23 0:00 ` Frank Manning
1997-03-25 0:00 ` Ken Garlington
1997-03-20 0:00 ` Robert I. Eachus
1997-03-20 0:00 ` Ariane-5: can you clarify? (Re: Please do not start a language war) Karel Th�nissen
1997-03-20 0:00 ` Nick Leaton
1997-03-20 0:00 ` Papers on the Ariane-5 crash and Design by Contract Robert I. Eachus
1997-03-20 0:00 ` Ariane-5: can you clarify? (Re: Please do not start a language war) Nick Leaton
1997-03-21 0:00 ` Papers on the Ariane-5 crash and Design by Contract Ulrich Windl
[not found] ` <tz8sp1qiywm.fsf@aimnet.com>
1997-03-21 0:00 ` ae59
1997-03-21 0:00 ` Alexander Anderson
1997-03-23 0:00 ` "Paul E. Bennett"
1997-03-21 0:00 ` Please do not start a language war (was " Jon S Anthony
1997-03-22 0:00 ` Bertrand Meyer
1997-03-22 0:00 ` Anders Pytte
1997-03-23 0:00 ` Steve Furlong
1997-03-24 0:00 ` Anders Pytte
1997-03-24 0:00 ` Simulating Eiffel-style assertions (was: Papers on the Ariane-5 crash and Design by Contract) Wolfgang Reddig
1997-03-24 0:00 ` Anders Pytte
1997-03-25 0:00 ` Wolfgang Reddig
1997-03-25 0:00 ` Anders Pytte
1997-03-31 0:00 ` Joachim Durchholz
1997-03-26 0:00 ` Alan Brain
1997-03-26 0:00 ` Wolfgang Reddig
1997-03-29 0:00 ` How old time languages survive EJon
1997-03-22 0:00 ` Papers on the Ariane-5 crash and Design by Contract Bertrand Meyer
1997-03-23 0:00 ` Dale Stanbrough
[not found] ` <3335E18E.33590565@eiffel.com>
1997-03-23 0:00 ` FUD (Re: Papers on the Ariane-5 crash and Design by Contract) Bertrand Meyer
1997-03-24 0:00 ` William Grosso
1997-03-24 0:00 ` Bertrand Meyer
1997-03-24 0:00 ` William Clodius
1997-03-24 0:00 ` Brad Appleton
1997-03-24 0:00 ` Papers on the Ariane-5 crash and Design by Contract Robert Dewar
1997-03-24 0:00 ` Manners (was Re: Papers on the Ariane-5 crash and Design by Contract) Bertrand Meyer
1997-03-25 0:00 ` the one and only real true kibo
1997-03-22 0:00 ` Papers on the Ariane-5 crash and Design by Contract Jon S Anthony
1997-03-28 0:00 ` Matt Kennel (Remove 'nospam' to reply)
1997-03-22 0:00 ` Ariane-5: can you clarify? (Re: Please do not start a language war) Stuart Yeates
1997-03-24 0:00 ` Papers on the Ariane-5 crash and Design by Contract Alexander Anderson
1997-03-24 0:00 ` Ariane-5: can you clarify? (Re: Please do not start a language war) Ken Garlington
1997-03-24 0:00 ` Papers on the Ariane-5 crash and Design by Contract Jon S Anthony
1997-03-24 0:00 ` Ken Garlington
1997-03-24 0:00 ` Ken Garlington
1997-03-27 0:00 ` Joachim Durchholz
1997-03-31 0:00 ` Ken Garlington
1997-04-06 0:00 ` Joachim Durchholz
1997-03-24 0:00 ` Ariane-5: can you clarify? (Re: Please do not start a language war) Nick Leaton
1997-03-24 0:00 ` Papers on the Ariane-5 crash and Design by Contract Robb Nebbe
1997-03-24 0:00 ` Ariane-5: can you clarify? (Re: Please do not start a language war) William Clodius
1997-03-24 0:00 ` Ken Garlington
1997-03-24 0:00 ` Papers on the Ariane-5 crash and Design by Contract Ken Garlington
1997-03-25 0:00 ` Robert I. Eachus
1997-03-25 0:00 ` Ariane-5: can you clarify? (Re: Please do not start a language war) David Starr
1997-03-25 0:00 ` Ken Garlington
1997-03-25 0:00 ` Ken Garlington
1997-03-26 0:00 ` Papers on the Ariane-5 crash and Design by Contract Ken Garlington
1997-03-26 0:00 ` Alexander Anderson
1997-03-26 0:00 ` Jon S Anthony
1997-03-27 0:00 ` Trust but verify (was " Robert I. Eachus
1997-03-28 0:00 ` Robert I. Eachus
1997-03-28 0:00 ` Jon S Anthony
1997-03-31 0:00 ` Ken Garlington
1997-03-23 0:00 ` the one and only real true kibo
-- strict thread matches above, loose matches on Subject: below --
1997-03-17 0:00 Marin David Condic, 561.796.8997, M/S 731-93
1997-03-20 0:00 Marin David Condic, 561.796.8997, M/S 731-93
1997-03-25 0:00 ` Nick Roberts
1997-03-24 0:00 Marin David Condic, 561.796.8997, M/S 731-93
1997-03-27 0:00 Marin David Condic, 561.796.8997, M/S 731-93
1997-04-03 0:00 Adrian B.Y. Hoe
1997-04-05 0:00 ` Nick Roberts
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