"Martin J. Maney" wrote:

> On Fri, 17 May 1996, terogers wrote:
>
> > With proper structured design and testing it is possible to arrive at a
> > probably reliable system design, but not a provably reliable design. The
>
> With respect to testing, Dijkstra said it long ago: testing is adequate to
> show the presence of faults, but never their absence [fairly close
> paraphrase here].  The only way in principle to prove a system reliable
> would be to construct a formal proof in parallel with the design - that's
> more or less the motivation behind the entire range of "structured"
> techniques.  Of course they're imperfect - they overprescribe in many
> ways, the dogmatic form of "thou shalt use no gotos" being an obvious
> example, and can't guarantee correct results - but that's the inevitable
> result of attempting to make what is bascially a style guide (structured
> programming) stand in for a far more rigorous method (formal correctness)
> that you can't afford to use.
>
> Sorry, your comment, in combination with the coffee just kicking in, set
> me off on a hot button topic there.  :-)

Sounds like you like structured techniques (or rather they way in which they
are applied) as much as I do <-:

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