Re: Ada Recursion with strings

[Ludovic Brenta <ludovic@ludovic-brenta.org>]

Niklas Holsti wrote:
> Jean-Pierre Rosen wrote:
> > Adam Beneschan a �crit :
> >
> >> Yep, the advantage of that is that if the people who design the
> >> Internet communication protocols suddenly decide that IP addresses are
> >> going to use 9-bit bytes, all you have to do is change one constant,
> >> rather than try to find all the 8's in your code and change them,
> >> which is more error-prone.
> >>
> > Reminds me of an old advice explaining why named constants were better
> > than numerical values. They took the example of Pi, saying it would make
> >  maintenance easier "should the value of Pi change" :-)

That's funny because I thought about the same thing when reading
Adam's comment.

> That reminds me of a former colleague, some decades ago, who was
> tearing his hair out because his astronomical calculations with a
> FORTRAN program were going wrong. Turns out he had the value of PI
> as a variable in a COMMON area, after an array, and an indexing
> error on this array was changing the value of PI, affecting several
> trigonometric formulae...

Looks like programmers have already made every mistake that could be
made at least once :) Actually, that's what brought me to Ada in the
first place. I thought to myself: "computer science and software
engineering have been in existence for 50 years; yet we keep on making
the same old stupid mistakes. Surely someone, somewhere, has found a
way to learn from our mistakes and prevent them in the future?"

--
Ludovic Brenta.