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From: fjh@mundook.cs.mu.OZ.AU (Fergus Henderson)
Subject: Re: Ariane 5 - not an exception?
Date: 1996/08/05
Message-ID: <4u582b$rj8@mulga.cs.mu.OZ.AU>#1/1
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references: <Dv45EJ.8r@fsa.bris.ac.uk> <4t9vdg$jfb@goanna.cs.rmit.edu.au>
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organization: Comp Sci, University of Melbourne
newsgroups: comp.software-eng,comp.lang.ada,comp.lang.pl1
Date: 1996-08-05T00:00:00+00:00
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Richard Riehle <rriehle@nunic.nu.edu> writes:

>  5) Unchecked Conversion
>
>     Ada practitioners have been preaching for years that this should not
>     be done without substantial examination and testing. One more example
>     of why unchecked_conversion is usually not a good idea. Sometimes it
>     is unavoidable, I know.

I agree that in general unchecked_conversions should be avoided,
but Ariane 5 wasn't an example of unchecked_conversion going wrong,
in fact it was just the opposite, it was an example of a checked
conversion going wrong.  If the conversion had been unchecked,
then the rocket may not have crashed (indeed the problem may have
gone unnoticed).

--
Fergus Henderson <fjh@cs.mu.oz.au>   |  "I have always known that the pursuit
WWW: <http://www.cs.mu.oz.au/~fjh>   |  of excellence is a lethal habit"
PGP: finger fjh@128.250.37.3         |     -- the last words of T. S. Garp.