From: "Alex R. Mosteo" <devnull@mailinator.com>
Subject: Re: private types
Date: Tue, 14 Mar 2006 09:47:10 +0100
Date: 2006-03-14T09:47:10+01:00 [thread overview]
Message-ID: <4416830E.50201@mailinator.com> (raw)
In-Reply-To: <sa4k6axpj1y.fsf@snoopy.microcomaustralia.com.au>
Brian May wrote:
>>>>>>"Jeffrey" == Jeffrey R Carter <spam.not.jrcarter@acm.not.spam.org> writes:
>
> >> MyInteger to be made visible outside the scope of PrivateType ?
> >> Doesnt it make the code less secure(for example,consider an
> >> "uninitialized" object of type PrivateType.MyInteger).
>
> Jeffrey> Because that's what private means in Ada.
>
> He does have a point though - some languages will initialise all
> variables to dummy values - this means you can get predictable results
> in code that (wrongly) uses them before setting them to a value.
>
> In this case it is possible to force initialisation (at least outside
> the package), as per another poster's suggestion, because it is a
> private type. Alternatively it is possible to turn it into a record
> type and provide a default value for the component, as per another
> post.
>
> In other cases it isn't so easy, e.g. any non-private non-record type.
>
> In fact, by default (at least last time I checked), gcc (or was that
> gnat) doesn't check the validity of parameters to functions if the
> type matches, even though the type hasn't been initialised and may
> just happen to contain an illegal value.
>
> I seem to recall Ada will initialise access types to null, and record
> components (if defaults given), but nothing else.
Access variables are initialized to null by language definition.
Normalize_Scalars pragma exists also, and Gnat has Initialize_Scalars I
think. These can give more control, but IMHO that's an after-the-bug
resort.
next prev parent reply other threads:[~2006-03-14 8:47 UTC|newest]
Thread overview: 93+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-03-13 19:58 private types ada_student
2006-03-13 20:27 ` Mark Lorenzen
2006-03-13 21:05 ` Pascal Obry
2006-03-13 21:07 ` ada_student
2006-03-13 21:45 ` Simon Wright
2006-03-14 4:51 ` Jeffrey R. Carter
2006-03-14 7:44 ` Brian May
2006-03-14 8:25 ` Ludovic Brenta
2006-03-14 8:47 ` Alex R. Mosteo [this message]
2006-03-17 4:33 ` Justin Gombos
2006-03-17 5:17 ` Brian May
2006-03-17 22:50 ` Justin Gombos
2006-03-18 1:17 ` Randy Brukardt
2006-03-18 2:17 ` Justin Gombos
2006-03-21 0:08 ` Randy Brukardt
2006-03-18 8:39 ` Uninitialized variables (was: Re: private types) Dirk Craeynest
2006-03-18 14:06 ` Gautier
2006-03-18 14:36 ` Uninitialized variables Jeffrey Creem
2006-03-21 0:22 ` Uninitialized variables (was: Re: private types) Randy Brukardt
2006-03-21 0:38 ` Randy Brukardt
2006-03-18 12:06 ` private types Martin Dowie
2006-03-18 12:47 ` Robert A Duff
2006-03-17 7:40 ` Maciej Sobczak
2006-03-17 16:41 ` Frank J. Lhota
2006-03-17 23:36 ` Justin Gombos
2006-03-18 1:32 ` Randy Brukardt
2006-03-18 3:21 ` Handling invalid objects Justin Gombos
2006-03-18 7:35 ` Jeffrey R. Carter
2006-03-18 16:10 ` Justin Gombos
2006-03-19 11:00 ` Simon Wright
2006-03-20 23:57 ` Randy Brukardt
2006-03-22 2:06 ` Justin Gombos
2006-03-22 5:23 ` tmoran
2006-03-22 8:48 ` Dmitry A. Kazakov
2006-03-22 9:24 ` Maciej Sobczak
2006-03-22 11:05 ` Dmitry A. Kazakov
2006-03-22 16:42 ` Maciej Sobczak
2006-03-22 18:06 ` Stefan Lucks
2006-03-23 13:20 ` Dmitry A. Kazakov
2006-03-18 8:57 ` Jacob Sparre Andersen
2006-03-19 19:07 ` Dr. Adrian Wrigley
2006-03-20 15:25 ` Robert A Duff
2006-03-19 22:06 ` Brian May
2006-03-20 21:17 ` Jeffrey R. Carter
2006-03-20 23:44 ` Randy Brukardt
2006-03-22 1:27 ` Justin Gombos
2006-03-18 9:20 ` private types Dmitry A. Kazakov
2006-03-17 13:18 ` Robert A Duff
2006-03-17 23:44 ` Justin Gombos
2006-03-18 9:24 ` Dmitry A. Kazakov
2006-03-18 12:56 ` Robert A Duff
2006-03-18 15:06 ` Justin Gombos
2006-03-19 9:35 ` Martin Krischik
2006-03-19 14:52 ` Peter C. Chapin
2006-03-19 15:08 ` Björn Persson
2006-03-19 16:34 ` Martin Krischik
2006-03-20 9:57 ` Maciej Sobczak
2006-03-20 10:58 ` Peter C. Chapin
2006-03-20 11:19 ` Peter C. Chapin
2006-03-20 13:06 ` Maciej Sobczak
2006-03-20 15:19 ` Robert A Duff
2006-03-20 16:47 ` James Dennett
2006-03-20 19:12 ` Martin Krischik
2006-03-21 7:27 ` Maciej Sobczak
2006-03-20 19:32 ` Martin Krischik
2006-03-21 7:41 ` Maciej Sobczak
2006-03-20 20:29 ` Simon Wright
2006-03-19 17:43 ` Larry Kilgallen
2006-03-19 22:11 ` Peter C. Chapin
2006-03-19 18:15 ` Robert A Duff
2006-03-19 19:20 ` Martin Krischik
2006-03-19 20:43 ` Dr. Adrian Wrigley
2006-03-20 15:01 ` Robert A Duff
2006-03-27 4:07 ` Dave Thompson
2006-03-20 9:40 ` Maciej Sobczak
2006-03-20 15:09 ` Robert A Duff
2006-03-21 8:07 ` Maciej Sobczak
2006-03-26 18:53 ` Robert A Duff
2006-03-19 19:27 ` Jeffrey R. Carter
2006-03-25 21:40 ` Robert A Duff
2006-03-26 0:10 ` Justin Gombos
2006-03-26 1:00 ` Robert A Duff
2006-03-26 6:37 ` Jeffrey R. Carter
2006-03-26 15:43 ` Justin Gombos
2006-03-26 16:32 ` Robert A Duff
2006-03-26 16:51 ` Robert A Duff
2006-03-26 19:41 ` Jeffrey R. Carter
2006-03-26 3:15 ` Frank J. Lhota
2006-03-26 18:28 ` Robert A Duff
2006-03-26 19:43 ` Jeffrey R. Carter
2006-03-26 19:59 ` Simon Wright
[not found] <bctruong.1.00117123@draper.com>
1999-07-28 0:00 ` Stanley R. Allen
1999-07-28 0:00 ` Thomas Hood
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