From: Robert A Duff <bobduff@shell01.TheWorld.com>
Subject: Re: What would be the Ada solution?
Date: Fri, 04 Feb 2011 11:57:42 -0500
Date: 2011-02-04T11:57:42-05:00 [thread overview]
Message-ID: <wcc8vxvyby1.fsf@shell01.TheWorld.com> (raw)
In-Reply-To: 0aa67233-4210-483b-b35c-8e872f87cb8f@r21g2000yqd.googlegroups.com
KK6GM <mjsilva@scriptoriumdesigns.com> writes:
> A colleague is working on some old code, written in C, that uses an
> "out of range" integer value to indicate no valid value. Thus, a
> default value (in this case 0x7FFFFFFF) means no value has been
> entered. All code that uses any values should check for this no-value
> and act accordingly, but of course not all the code actually does
> that, and there are odd cases where the no-value value gets processed
> as a valid value and then Bad Things Happen.
>
> I'm curious what the Ada approach to this issue would be, the issue
> being to differentiate between valid and invalid values, and to catch
> (compile time or run time) any manipulation of an invalid value as if
> it were a valid value.
I suggest you read these two "gems":
http://www.adacore.com/2010/04/05/gem-82/
http://www.adacore.com/2010/04/05/gem-83/
- Bob
next prev parent reply other threads:[~2011-02-04 16:57 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-02-04 16:33 What would be the Ada solution? KK6GM
2011-02-04 16:38 ` Mark Lorenzen
2011-02-04 16:57 ` Robert A Duff [this message]
2011-02-04 18:59 ` Georg Bauhaus
2011-02-04 19:33 ` Robert A Duff
2011-02-04 17:14 ` mockturtle
2011-02-04 17:47 ` Robert A Duff
2011-02-04 17:26 ` Dmitry A. Kazakov
2011-02-04 17:38 ` Robert A Duff
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