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From: "Randy Brukardt" <randy@rrsoftware.com>
Subject: Re: Language lawyer question: task activation
Date: Fri, 27 Feb 2009 17:29:10 -0600
Date: 2009-02-27T17:29:10-06:00	[thread overview]
Message-ID: <go9t07$lht$1@munin.nbi.dk> (raw)
In-Reply-To: 1vcaimc8kjj30$.kf3rsd670ebp$.dlg@40tude.net

"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message 
news:1vcaimc8kjj30$.kf3rsd670ebp$.dlg@40tude.net...
...
>> When a procedure P(Object: out T) returns, there
>> is a yield (in Object).
>
> No, it is not so. The actual of Object out T is constructed *prior* to 
> call
> to P. In contrast the "actual" of F return T is not constructed (when T is
> limited). This is exactly the thing that worries me. Because it makes out 
> T
> and return T different, while they are evidently same.

To you, maybe, but not in Ada. Even in Ada 83, "out T" and "return T" are 
different:

   procedure Foo (P : out String);
   function Bar return String;

Bar creates a *new* object with unknown bounds; Foo takes an *existing* 
object with whatever bounds it has. Totally different animals. 
Build-in-place is a rather natural extension to this model. (It's annoying 
that we don't have a way to do return-by-reference as well, but that's 
another topic).

Now, I realize you have rather firm ideas about what represents a "proper 
type model", but that's pretty much irrelevant to the Ada type model (which 
isn't going to change for obvious compatibility reasons).

                        Randy.





  reply	other threads:[~2009-02-27 23:29 UTC|newest]

Thread overview: 44+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-02-19 17:37 Language lawyer question: task activation Adam Beneschan
2009-02-19 17:57 ` Dmitry A. Kazakov
2009-02-19 23:57   ` Robert A Duff
2009-02-20 13:22     ` Dmitry A. Kazakov
2009-02-23  7:36       ` Jean-Pierre Rosen
2009-02-20  5:43   ` christoph.grein
2009-02-20 10:44     ` Dmitry A. Kazakov
2009-02-20 11:14       ` christoph.grein
2009-02-20 12:07         ` mockturtle
2009-02-20 13:22           ` Dmitry A. Kazakov
2009-02-20 16:45             ` Georg Bauhaus
2009-02-20 18:41               ` Dmitry A. Kazakov
2009-02-20 22:19                 ` Georg Bauhaus
2009-02-21  8:31                   ` Dmitry A. Kazakov
2009-02-27 23:29                     ` Randy Brukardt [this message]
2009-02-28  8:13                       ` Why constructing functions is a mess [was Language lawyer question: task activation (was: Language lawyer question: task activation)) Dmitry A. Kazakov
2009-02-28 12:20                         ` Why constructing functions is a mess [was Language lawyer question: task activation Georg Bauhaus
2009-02-28 13:45                           ` Dmitry A. Kazakov
2009-02-28 15:36                             ` Georg Bauhaus
2009-02-28 16:22                               ` Dmitry A. Kazakov
2009-02-28 17:19                                 ` Georg Bauhaus
2009-02-28 17:48                                   ` Dmitry A. Kazakov
2009-02-28 18:39                                     ` Georg Bauhaus
2009-02-28 20:17                                       ` Dmitry A. Kazakov
2009-03-02 16:13                                         ` Georg Bauhaus
2009-03-02 17:46                                           ` Dmitry A. Kazakov
2009-03-02 18:50                                             ` Georg Bauhaus
2009-03-02 21:02                                               ` Dmitry A. Kazakov
2009-03-03  7:04                                                 ` christoph.grein
2009-03-03  8:45                                                   ` Dmitry A. Kazakov
2009-03-03  9:27                                                     ` christoph.grein
2009-03-03  9:34                                                       ` Dmitry A. Kazakov
2009-03-03 19:13                                                       ` Pascal Obry
2009-03-04  5:29                                                         ` christoph.grein
2009-03-04  8:32                                                           ` Dmitry A. Kazakov
2009-03-04  9:05                                                             ` christoph.grein
2009-03-04  9:47                                                               ` Dmitry A. Kazakov
2009-02-28 23:12                             ` Maciej Sobczak
2009-03-01  8:23                               ` Dmitry A. Kazakov
2009-02-19 23:54 ` Robert A Duff
2009-02-20 10:18 ` Robert_Matthews
2009-02-20 10:34   ` christoph.grein
2009-02-20 14:16   ` Robert A Duff
2009-02-20 16:57     ` Robert_Matthews
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