From: Ludovic Brenta <ludovic@ludovic-brenta.org>
Subject: Re: another way to shoot yourself in the foot?
Date: Tue, 24 Jun 2008 22:50:10 +0200
Date: 2008-06-24T22:50:10+02:00 [thread overview]
Message-ID: <87abhablrx.fsf@ludovic-brenta.org> (raw)
In-Reply-To: wcc7icer2vw.fsf@shell01.TheWorld.com
Robert A Duff writes:
> But in Ada 95, if you say:
>
> P(F(...));
>
> where F returns limited, you are not passing a limited object,
> but an implicit reference to some object that already existed before the
> call to F.
[...]
> In Ada 2005, functions always return newly-created objects, which I
> think is appropriate.
This makes me wonder whether there is an actual difference in the way
the compiler handles such returns. For example, has GNAT changed a
lot in this area? Do the Ada 95 and Ada 2005 compatibility modes use
antirely different compilation strategies?
> if F(...).Flag then ...
>
> The last one is pretty silly -- it creates a new limited object,
> grabs a boolean flag out of it, and then throws the whole thing
> away.
Yes but "grabbing a boolean flag" might consist in passing the limited
object as a parameter to a primitive function named Flag, which might
then pass it down to any number of subprograms with all sorts of side
effects. One could write an arbitrarily large program like this :)
--
Ludovic Brenta.
next prev parent reply other threads:[~2008-06-24 20:50 UTC|newest]
Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-06-20 9:03 another way to shoot yourself in the foot? fedya_fedyakoff
2008-06-20 9:34 ` Dmitry A. Kazakov
2008-06-20 9:48 ` fedya_fedyakoff
2008-06-20 10:01 ` Ludovic Brenta
2008-06-20 10:05 ` christoph.grein
2008-06-20 10:26 ` Dmitry A. Kazakov
2008-06-20 16:12 ` Adam Beneschan
2008-06-20 15:48 ` Adam Beneschan
2008-06-20 19:27 ` Robert A Duff
2008-06-20 23:37 ` Jeffrey R. Carter
2008-06-21 8:56 ` Dmitry A. Kazakov
2008-06-22 20:44 ` Robert A Duff
2008-06-23 7:49 ` Dmitry A. Kazakov
2008-06-24 4:02 ` george.priv
2008-06-24 7:30 ` Dmitry A. Kazakov
2008-06-24 17:16 ` Robert A Duff
2008-06-24 19:15 ` Jeffrey R. Carter
2008-06-24 20:31 ` Robert A Duff
2008-06-24 20:50 ` Ludovic Brenta [this message]
2008-06-24 23:02 ` Robert A Duff
2008-06-24 23:42 ` Georg Bauhaus
2008-06-24 21:24 ` Jeffrey R. Carter
2008-06-24 23:24 ` Robert A Duff
2008-06-25 15:07 ` Adam Beneschan
2008-06-24 14:59 ` Adam Beneschan
2008-06-24 16:41 ` Dmitry A. Kazakov
2008-06-24 17:20 ` Robert A Duff
2008-06-24 17:52 ` Dmitry A. Kazakov
2008-06-24 23:35 ` Georg Bauhaus
2008-06-25 8:09 ` Dmitry A. Kazakov
2008-06-25 10:32 ` Georg Bauhaus
2008-06-25 12:06 ` Dmitry A. Kazakov
2008-06-22 20:37 ` Robert A Duff
2008-06-22 21:25 ` Jeffrey R. Carter
2008-07-04 20:52 ` Colin Paul Gloster
2008-07-04 22:15 ` (see below)
2008-07-05 16:06 ` Colin Paul Gloster
2008-07-05 13:38 ` Gary Scott
2008-07-05 16:42 ` Colin Paul Gloster
2008-07-05 19:00 ` Gary Scott
2008-07-09 19:39 ` Colin Paul Gloster
2008-07-09 20:35 ` Richard Maine
2008-07-09 22:49 ` Terence
2008-07-10 1:07 ` Gary Scott
2008-07-10 14:10 ` Colin Paul Gloster
2008-07-10 14:57 ` fj
2008-07-10 16:47 ` Richard Maine
2008-07-10 17:03 ` Dick Hendrickson
2008-07-10 17:26 ` Craig Powers
2008-07-10 19:55 ` James Giles
2008-07-10 20:45 ` Dick Hendrickson
2008-07-10 21:22 ` Richard Maine
2008-07-10 21:29 ` Craig Powers
2008-07-10 20:45 ` Craig Powers
2008-07-10 19:51 ` James Giles
2008-07-11 15:02 ` Colin Paul Gloster
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