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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Re-write a file in Ada
Date: Tue, 19 Jan 2016 09:54:36 -0700
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Xref: news.eternal-september.org comp.lang.ada:29168
Date: 2016-01-19T09:54:36-07:00
List-Id: <comp.lang.ada>

On 01/19/2016 07:35 AM, Simon Wright wrote:
> 
> I think you must mean
> 
>    while not End_Of_File (This_File) loop
> 
> which isn't really much simpler than
> 
>    loop
>       exit when End_Of_File (This_File);

In fact, it's less simple, because it involves thinking about the continuation
condition and using negative logic. It's more natural to think about the exit
condition than the continuation condition, and positive logic is simpler than
negative.

At the Ada Launch on 1980 Dec 10, Ichbiah said that Ada had a while loop to
facilitate automatic translation from other languages, but new code should use exit.

-- 
Jeff Carter
"So if I understand 'The Matrix Reloaded' correctly, the Matrix is
basically a Microsoft operating system--it runs for a while and
then crashes and reboots. By design, no less. Neo is just a
memory leak that's too hard to fix, so they left him in ... The
users don't complain because they're packed in slush and kept
sedated."
Marin D. Condic
65