Does Python really follow its philosophy of "Readability counts"?

Bruno Desthuilliers bdesth.quelquechose at
Sun Jan 18 16:06:58 CET 2009

Paul Rubin a écrit :
> Bruno Desthuilliers <bdesth.quelquechose at> writes:
>> Once again, there's quite a lot to learn from
>> the story of Ariane 5.
> Do you know what actually happened with Ariane 5?

*yes I do* - else I wouldn't mention it. Thanks.

>  The failure was
> because "smart" humans overrode the language enforced protection by
> casting a floating point number down to a 16-bit integer, which worked
> ok in Ariane 4, but failed with an overflow on Ariane 5 where bigger
> numbers were involved.

The failure was because a module tested, QA'd and certified within a 
given context (in which it was ok to drop the builtin error handling) 
was reused in a context where it was not ok. And the point is exactly 
that : no *technology* can solve this kind of problem, because it is a 
*human* problem (in that case, not taking time to repass the whole specs 
/ tests / QA process given context change).

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