From: Rick DeNatale <rick.denatale@...>
Date: 2008-04-16T12:59:47+09:00
Subject: Re: Ada vs Ruby

On Tue, Apr 15, 2008 at 10:40 PM, Phillip Gawlowski
<cmdjackryan@googlemail.com> wrote:
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>  Rick DeNatale wrote:
>
>  |
>  | Amen, Sister!  And languages which rely on static typing have a
>  | tendency to do much more random things when things go wrong.  Language
>  | like Ruby tend to have a more vigilant runtime.
>  |
>
>  I wouldn't fly in an aeroplane that relies on the runtime to catch errors.
>
>  Take the Space Shuttle as an extreme. Does the language breed perfection
>  in the Shuttle's source, or is it the process NASA uses?
>
>  I bet you dollars to doughnuts that it is the process, with
>  more-than-due-diligence in writing and testing the software. That the
>  requirements are clear cut and well understood is another bonus.
>
>  Languages don't matter. Compilers don't matter. Process, however, does.
>
>  Or methodology. TDD has its benefits, as does BDD. Without these, the
>  Agile way wouldn't work. QA is the key, not that language.

I was pondering this thread earlier today, and before I pitched in,
and was going to draw an analogy with Frank Borman's comments during
the Senate commitee hearing on the Apollo 1 fire.  He said that the
real cause of the fire, was "a lack of imagination" about the dangers
of doing ground testing with the spacecraft filled with pure O2 at
sea-level atmospheric pressure.

Relying on static-typing to 'prevent' fatal errors exhibits the same
kind of lack of imagination about the range of possible failure modes.
 Nothing is perfect, but I'll take disciplined testing over relying on
ceremonial static typing any day.

>  Don't just take my word for it:
>
>  http://www.nap.edu/html/statsoft/chap2.html
>
>  The above link has a case study on NASA's process for developing the
>  Space Shuttle's flight control software.

Of course even with good process, it's still hard to get it right the
first time, remember "the bug heard round the world," which kept
Columbia on the pad during the first attempt to launch STS-1?

http://portal.acm.org/citation.cfm?id=1005928.1005929

-- 
Rick DeNatale

My blog on Ruby
http://talklikeaduck.denhaven2.com/