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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: not null
Date: Thu, 5 Mar 2009 16:06:22 +0100
Date: 2009-03-05T16:06:22+01:00	[thread overview]
Message-ID: <1bydip4ahvzhy$.fluevvq5h3pi$.dlg@40tude.net> (raw)
In-Reply-To: j8dvq4lmb7p7hr70h7k3elqv5k8lrvjcv5@4ax.com

On Thu, 05 Mar 2009 11:32:13 +0000, Brian Drummond wrote:

> On Wed, 4 Mar 2009 17:47:03 -0800 (PST), Adam Beneschan <adam@irvine.com> wrote:
> 
>>You could also make the "end of list" point to some special dummy
>>object. 
> 
> I don't see that as semantically different from a null pointer.
> Which perhaps just helps to make your point

Well, many lists are never empty. Such lists (single or doubly-linked) can
be made circular. This strategy has several advantages. One of them is that
null pointers are never used. (An item outside any list points to itself.)

(Granted, a wrongly implemented list iteration may cycle rather than
crash.)

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de



  reply	other threads:[~2009-03-05 15:06 UTC|newest]

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-03-04 14:44 not null Georg Bauhaus
2009-03-04 14:56 ` Hyman Rosen
2009-03-04 15:22   ` Georg Bauhaus
2009-03-04 16:16     ` Adam Beneschan
2009-03-05 14:24       ` Georg Bauhaus
2009-03-05 16:07         ` Adam Beneschan
2009-03-06  1:07       ` Hibou57 (Yannick Duchêne)
2009-03-04 16:09   ` Adam Beneschan
2009-03-04 20:38     ` Dmitry A. Kazakov
2009-03-05  1:54       ` Adam Beneschan
2009-03-05  8:42         ` Dmitry A. Kazakov
2009-03-05  1:32     ` Brian Drummond
2009-03-05  1:47       ` Adam Beneschan
2009-03-05 11:32         ` Brian Drummond
2009-03-05 15:06           ` Dmitry A. Kazakov [this message]
2009-03-05 13:57         ` Georg Bauhaus
2009-03-05 19:53       ` Jack Mitchell
2009-03-05  8:49     ` Jacob Sparre Andersen
2009-03-05 16:10       ` Adam Beneschan
2009-03-05 17:20         ` Jacob Sparre Andersen
2009-03-06  1:04     ` Hibou57 (Yannick Duchêne)
2009-03-06 12:01     ` Harald Korneliussen
2009-03-06 12:43       ` Jacob Sparre Andersen
2009-03-06 13:05         ` Harald Korneliussen
2009-03-06 15:21       ` Dmitry A. Kazakov
2009-03-06 16:59         ` Harald Korneliussen
2009-03-06 17:48           ` Dmitry A. Kazakov
2009-03-06 20:05             ` Georg Bauhaus
2009-03-06 21:31               ` Dmitry A. Kazakov
2009-03-04 16:19   ` Robert A Duff
2009-03-04 20:39 ` Colin Paul Gloster
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