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> Well, Gérard, being a software developer by profession, I'd have to tell
you that n.d. results lead to "trapping" in a lot of languages. There are
some, like ADA, or PLI, where you can handle errors in an "On Error"
routine, but usually they tend to make the programs less logical and usable.
>
> It was one of the very first rules that I learned, to prevent a division
by 0 beforehand.
>
> I mean, what's the logic behind your question? You can either check for
"division by zero" before you make the division, or your can handle the
"division by zero" exception afterwards. Where's the big benefit?
>
> IMHO, not checking for div by 0 is sloppy pogramming, and it is totally
against the logic of Oberon, where you are expressis verbis told that you
should assert all that is necessary for any procedure etc. before you
perform it.
Thank you René,
You may be right. Obviously, a program is better if there is no error
inside. I have to think a little more on this point.
I'm in a situation where there can be a lot af arithmetic errors, but where
these errors are harmless: the important points are that the program must
never stop (no trap) and that the user is warned that an error has occurred
somewhere and that the result is unreliable. It seemed to me that a
centralized way of dealing with these errors could be a solution. Of course,
it may happen that a non harmless error occurrs too and is not trapped. In
this case, the program could become unstable. So...
Nevertheless, I think it's impossible to do in BB what I expected.
Regards.
Gérard
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Received on Tue Sep 14 2004 - 17:53:16 UTC