From: Niklas Holsti <nobody@nowhere.fi>
Subject: Re: Half Constrained Array Types and Slices
Date: Sat, 11 Mar 2006 10:38:52 +0200
Date: 2006-03-11T10:38:52+02:00 [thread overview]
Message-ID: <44128c9a$0$25335$39db0f71@news.song.fi> (raw)
In-Reply-To: <jXpQf.4653$6I.4184@newsread3.news.pas.earthlink.net>
Jeffrey R. Carter wrote:
> Randy Brukardt wrote:
>
>> ... Empty arrays are never very useful, ...
>
> FWIW, my opinions are closer to Brukardt's than to Duff's. However, null
> arrays are often useful; there are whole classes of recursive algorithms
> that look like
>
> return G (X (X'First) ) & F (X (Index'Succ (X'First) .. X'Last) );
>
> with a null array terminating the recursion.
I second Jeffrey's opinion. I find that empty arrays are very
useful for my applications (program analysis). I could live
with a language where A'First and A'Last are available only when
A'Length > 0 and might raise Constraint_Error if A'Length = 0.
However, "for I in A'Range loop .. end loop" should work even
when A'Length = 0 (and do nothing in that case).
--
Niklas Holsti
Tidorum Ltd
niklas holsti tidorum fi
. @ .
prev parent reply other threads:[~2006-03-11 8:38 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-03-02 5:00 Half Constrained Array Types and Slices Jeffrey R. Carter
2006-03-02 8:34 ` Dmitry A. Kazakov
2006-03-02 15:34 ` Georg Bauhaus
2006-03-02 19:37 ` Dmitry A. Kazakov
2006-03-02 20:06 ` Jeffrey R. Carter
2006-03-02 20:37 ` Dmitry A. Kazakov
2006-03-02 21:01 ` Robert A Duff
2006-03-02 20:40 ` Robert A Duff
2006-03-02 14:32 ` Larry Kilgallen
2006-03-02 20:08 ` Jeffrey R. Carter
2006-03-02 20:48 ` Robert A Duff
2006-03-06 2:16 ` Larry Kilgallen
2006-03-06 18:50 ` Martin Krischik
2006-03-02 20:38 ` Robert A Duff
2006-03-03 5:15 ` Jeffrey R. Carter
2006-03-03 8:57 ` Dmitry A. Kazakov
2006-03-03 23:41 ` Robert A Duff
2006-03-06 17:50 ` Jeff Carter
2006-03-06 18:31 ` Dmitry A. Kazakov
2006-03-07 19:02 ` Jeff Carter
2006-03-08 14:29 ` Dmitry A. Kazakov
2006-03-09 22:44 ` Robert A Duff
2006-03-10 8:46 ` Dmitry A. Kazakov
2006-03-06 19:49 ` Stefan Lucks
2006-03-08 17:36 ` brian.b.mcguinness
2006-03-08 17:56 ` Jeff Carter
2006-03-09 22:36 ` Robert A Duff
2006-03-10 4:28 ` Jeffrey R. Carter
2006-03-10 8:46 ` Dmitry A. Kazakov
2006-03-10 17:33 ` Robert A Duff
2006-03-10 21:24 ` Dmitry A. Kazakov
2006-03-10 17:38 ` Robert A Duff
2006-03-11 0:19 ` Randy Brukardt
2006-03-11 1:43 ` Jeffrey R. Carter
2006-03-11 8:38 ` Niklas Holsti [this message]
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