From: "G.B." <rm-dash-bau-haus@dash.futureapps.de>
Subject: Re: The future of Spark . Spark 2014 : a wreckage
Date: Tue, 09 Jul 2013 13:13:36 +0200
Date: 2013-07-09T13:13:36+02:00 [thread overview]
Message-ID: <51dbf060$0$6569$9b4e6d93@newsspool3.arcor-online.net> (raw)
In-Reply-To: <1gs2slsmkpvbf.a9h84b9jcowi$.dlg@40tude.net>
On 09.07.13 10:58, Dmitry A. Kazakov wrote:
> On Tue, 09 Jul 2013 10:30:59 +0200, Georg Bauhaus wrote:
>
>> On 09.07.13 09:40, Dmitry A. Kazakov wrote:
>>> On Mon, 08 Jul 2013 22:59:30 +0200, Florian Weimer wrote:
>>>
>>>> * vincent diemunsch:
>>>>
>>>>> Same specification in Spark 2014 :
>>>>> procedure Swap
>>>>> with Global => (In_Out => (X, Y)),
>>>>> Depends => (X => Y, -- to be read as "X depends on Y"
>>>>> Y => X); -- to be read as "Y depends on X"
>>>>>
>>>>> How are we supposed to guess that "X => Y" means X depends on Y, if
>>>>> the arrow goes from X to Y ? In the literature, Flow analysis use
>>>>> always Information Flow where arrows follows the real move of
>>>>> information. See for instance "SPARK the proven approach of High
>>>>> Integrity Software" from John Barn page 311 or the "Dragon Book"
>>>>> (Compilers : principles, techniques and tools).
>>>>
>>>> This is nothing new. Boolean implication p → q is already written as
>>>> P <= Q in Ada.
>>>
>>> Where?
>>
>> In Boolean expressions. With obvious, I think, abbreviations
>> and referring to ordering of (False, True), and (0, 1),
>>
>> p q | p → q (p <= q)
>> -----------------------
>> 1 1 | 1 True
>> 1 0 | 0 False
>> 0 1 | 1 True
>> 0 0 | 1 True
>
> This is p=>q
"Boolean implication p → q is already written as
P <= Q in Ada."
As shown above. "=>" has no "Boolean" meaning in Ada.
(It has, in Prolog.) In implementation defined aspects,
GNAT is free to assign "depends" to "=>", UML style.
I guess we need to adapt to even more overloadings,
since symbolophobia is part of Ada culture.
next prev parent reply other threads:[~2013-07-09 11:13 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-08 17:56 The future of Spark . Spark 2014 : a wreckage vincent.diemunsch
2013-07-08 19:24 ` Simon Wright
2013-07-08 20:59 ` Florian Weimer
2013-07-09 7:40 ` Dmitry A. Kazakov
2013-07-09 8:30 ` Georg Bauhaus
2013-07-09 8:58 ` Dmitry A. Kazakov
2013-07-09 10:27 ` G.B.
2013-07-09 11:13 ` G.B. [this message]
2013-07-09 15:14 ` Adam Beneschan
2013-07-09 22:51 ` Robert A Duff
2013-07-10 7:49 ` Dmitry A. Kazakov
2013-07-10 8:21 ` Georg Bauhaus
2013-07-08 21:32 ` Randy Brukardt
2013-07-09 7:28 ` Dmitry A. Kazakov
2013-07-09 11:29 ` Simon Wright
2013-07-09 12:22 ` Dmitry A. Kazakov
2013-07-09 20:37 ` Randy Brukardt
2013-07-10 10:03 ` Dmitry A. Kazakov
2013-07-10 23:21 ` Randy Brukardt
2013-07-11 7:44 ` Dmitry A. Kazakov
2013-07-11 22:28 ` Randy Brukardt
2013-07-12 8:02 ` Dmitry A. Kazakov
2013-07-12 21:16 ` Randy Brukardt
2013-07-14 10:19 ` Dmitry A. Kazakov
2013-07-14 15:57 ` Georg Bauhaus
2013-07-16 0:16 ` Randy Brukardt
2013-07-17 1:30 ` Shark8
2013-07-17 23:08 ` Randy Brukardt
2013-07-18 7:19 ` Dmitry A. Kazakov
2013-07-19 4:36 ` Randy Brukardt
2013-07-16 0:13 ` Randy Brukardt
2013-07-16 8:37 ` Dmitry A. Kazakov
2013-07-16 22:13 ` Randy Brukardt
2013-07-17 7:59 ` Dmitry A. Kazakov
2013-07-17 23:26 ` Randy Brukardt
2013-07-18 7:37 ` Dmitry A. Kazakov
2013-07-19 4:32 ` Randy Brukardt
2013-07-19 7:16 ` Dmitry A. Kazakov
2013-07-20 5:32 ` Randy Brukardt
2013-07-20 9:06 ` Dmitry A. Kazakov
2013-07-12 1:01 ` Slow? Ada?? Bill Findlay
2013-07-09 7:57 ` The future of Spark . Spark 2014 : a wreckage Stefan.Lucks
2013-07-09 20:46 ` Randy Brukardt
2013-07-10 8:03 ` Stefan.Lucks
2013-07-10 12:46 ` Simon Wright
2013-07-10 23:10 ` Randy Brukardt
2013-07-11 19:23 ` Stefan.Lucks
2013-07-12 0:21 ` Randy Brukardt
2013-07-12 9:12 ` Stefan.Lucks
2013-07-12 20:47 ` Randy Brukardt
2013-08-05 5:43 ` Paul Rubin
2013-07-10 12:19 ` vincent.diemunsch
2013-07-10 16:02 ` Simon Wright
2013-07-11 0:36 ` Randy Brukardt
2013-07-11 6:19 ` Simon Wright
2013-07-11 23:11 ` Randy Brukardt
2013-07-11 10:10 ` vincent.diemunsch
2013-07-11 14:23 ` Dmitry A. Kazakov
2013-07-12 0:07 ` Randy Brukardt
2013-07-12 0:00 ` Randy Brukardt
2013-07-12 7:25 ` Simon Wright
2013-07-12 20:07 ` Randy Brukardt
2013-07-12 14:23 ` Robert A Duff
2013-07-12 20:14 ` Randy Brukardt
2013-07-11 23:50 ` Shark8
2013-07-08 23:18 ` Peter C. Chapin
2013-07-09 7:34 ` Stefan.Lucks
2013-07-09 15:21 ` Adam Beneschan
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