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Date: Thu, 05 Mar 2009 14:57:11 +0100
From: Georg Bauhaus <rm.dash-bauhaus@futureapps.de>
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Subject: Re: not null
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Date: 2009-03-05T14:57:12+01:00
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Adam Beneschan schrieb:

> You could also make the "end of list" point to some special dummy
> object.  That would probably be better than forcing the list to be
> circular, but again just as pointless.  I believe my earlier comment,
> that the same set of mistakes applies as to a language that involves
> null reference, but the syntax of those mistakes is different, applies
> to both of these "solutions".

Or an Admin object pointing to itself or else to the real nodes
that are end nodes if they point to themselves, ... etc., I'd guess.

Where null values are probably inferior compared to
special objects is when "null.all" yields an access
error (at best; SEGFAULT or similar when checks have been suppressed).
To me, this exception is from the set of most unspecific exceptions
I can think of.  I'd prefer something more specific, maybe
related to tampering with the elements of the list, for example.