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From: Bob Duff <bobduff@theworld.com>
Newsgroups: comp.lang.ada
Subject: Re: Strange error
Date: Fri, 23 Jan 2015 20:34:04 -0500
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Xref: news.eternal-september.org comp.lang.ada:24725
Date: 2015-01-23T20:34:04-05:00
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"Randy Brukardt" <randy@rrsoftware.com> writes:

> "Laurent" <daemon2@internet.lu> wrote in message 
> news:3fa7d4c4-f9fe-4d00-9034-a348802087a9@googlegroups.com...
> ...
>> How do you professionals prevent such stupid errors? I am just a noob and 
>> playing
>> a bit around so it has no impact on anything.
>
> You don't (or at least, I don't). I seem to write loops that don't loop
> (forgot the P := P.Next) all the time.

"don't loop"?  That loops too much.  ;-)

I tend to write the boilerplate first:

    while P /= null loop
        
        P := P.Next;
    end loop;

Then go back and fill in the body of the loop.  So I don't usually
make that particural mistake.  Anyway, I think GNAT will give a warning
about that.

But in Ada 2012, we have iterators, which largely solves the problem.
Put all your eggs in one basket, and if the iterator works, then all
the myriad "for" loops around the code will work.

- Bob