From: "Nick Roberts" <nickroberts@adaos.worldonline.co.uk>
Subject: Re: List container strawman 1.1
Date: Tue, 6 Nov 2001 16:42:02 -0000
Date: 2001-11-06T16:42:02+00:00 [thread overview]
Message-ID: <9s941i$11mrei$3@ID-25716.news.dfncis.de> (raw)
In-Reply-To: mailman.1005002950.9554.comp.lang.ada@ada.eu.org
"Eric Merritt" <cyberlync@yahoo.com> wrote in message
news:mailman.1005002950.9554.comp.lang.ada@ada.eu.org...
> A singleton is a generally an object of which there is
> only one instance throughout the entire application.
> That means that accessed from anywhere in the program
> it will return the same list, in effect it is only
> instantiated once. That instance is then returned any
> time a new list is called for. So any elements added
> to the list are available thought the application.
> Basically a Singleton is a single instance of an
> object, ie there can never be more then one instance
> singleton object in an application.
That may be the meaning other languages, but not Ada! I intended the word
('singleton') in the mathematical sense of a set with only one element. Okay
so we're not talking about a set, but a list, but I think the meaning is
fairly obvious. In a program, code such as:
Team(England,Jumping,Ladies) := Singleton(HRH_Princess_Anne);
would help to emphasise that a list was being constructed that comprised
only one element. It would contrast usefully, I think, with a multiple
constructor:
Team(USA,TF_Relay_4x400m,Men) :=
To_List((Alvin_Harrison, Antonio_Pettigrew, Calvin_Harrison,
Michael_Johnson));
Of course, one alternative is not to have a 'singleton' constructor. It's
only a convenience:
Team(England,Jumping,Ladies) := To_List((1 => HRH_Princess_Anne));
I think I'd prefer having it, though.
--
Nick Roberts
next prev parent reply other threads:[~2001-11-06 16:42 UTC|newest]
Thread overview: 90+ messages / expand[flat|nested] mbox.gz Atom feed top
2001-11-02 20:29 List container strawman 1.1 Ted Dennison
2001-11-02 21:00 ` Larry Kilgallen
2001-11-02 21:08 ` Ted Dennison
2001-11-02 21:43 ` Larry Kilgallen
2001-11-02 21:20 ` Darren New
2001-11-02 23:33 ` Jeffrey Carter
2001-11-03 0:19 ` Darren New
2001-11-03 7:03 ` Ted Dennison
2001-11-02 21:45 ` Eric Merritt
2001-11-02 22:52 ` Larry Kilgallen
2001-11-03 7:09 ` Ted Dennison
2001-11-04 0:30 ` Nick Roberts
2001-11-05 12:40 ` Eric Merritt
2001-11-05 22:26 ` Nick Roberts
2001-11-05 23:28 ` Eric Merritt
2001-11-06 16:42 ` Nick Roberts [this message]
2001-11-06 17:24 ` Stephen Leake
2001-11-06 18:28 ` Eric Merritt
2001-11-06 22:17 ` Nick Roberts
2001-11-07 19:31 ` Stephen Leake
2001-11-07 22:55 ` Nick Roberts
2001-11-10 3:17 ` Ted Dennison
2001-11-10 3:31 ` Darren New
2001-11-13 16:47 ` Stephen Leake
2001-11-13 17:21 ` Darren New
2001-11-13 20:36 ` Ted Dennison
2001-11-13 23:48 ` Ben Place
2001-11-14 4:01 ` Nick Roberts
2001-11-14 16:10 ` Jeffrey Carter
2001-11-14 19:12 ` Ted Dennison
2001-11-14 22:32 ` Jeffrey Carter
[not found] ` <_mzI7.24675 <3BF2F0E7.5DD40B4B@boeing.com>
2001-11-15 3:49 ` Nick Roberts
2001-11-10 3:07 ` Ted Dennison
2001-11-10 14:18 ` Florian Weimer
2001-11-13 16:48 ` Stephen Leake
2001-11-06 18:21 ` Eric Merritt
2001-11-08 11:53 ` Simon Wright
2001-11-06 16:30 ` Darren New
2001-11-06 18:19 ` Eric Merritt
2001-11-04 4:55 ` Larry Hazel
[not found] ` <3BE31DD5.FF96AFE0@san.rr.com>
2001-11-03 7:07 ` Ted Dennison
2001-11-03 18:59 ` Jeffrey Carter
2001-11-04 19:07 ` Darren New
2001-11-04 22:21 ` Jeffrey Carter
2001-11-04 23:43 ` James Rogers
2001-11-05 18:09 ` Darren New
2001-11-05 22:59 ` Jeffrey Carter
2001-11-04 20:56 ` Jean-Marc Bourguet
2001-11-05 20:00 ` Ted Dennison
2001-11-05 20:27 ` Darren New
2001-11-05 20:54 ` Ted Dennison
2001-11-05 22:30 ` Darren New
2001-11-08 10:50 ` Ehud Lamm
2001-11-05 9:53 ` Mike Ovenden
2001-11-05 14:37 ` Jean-Marc Bourguet
2001-11-05 20:03 ` Ted Dennison
2001-11-06 8:52 ` Jean-Marc Bourguet
2001-11-05 16:01 ` Marin David Condic
2001-11-05 20:06 ` Ted Dennison
2001-11-05 20:45 ` Marin David Condic
2001-11-08 10:54 ` Ehud Lamm
2001-11-08 19:30 ` Marin David Condic
2001-11-08 22:06 ` Nick Roberts
2001-11-10 18:15 ` Simon Wright
2001-11-11 21:33 ` Pascal Obry
2001-11-11 21:55 ` Ehud Lamm
2001-11-05 22:37 ` Nick Roberts
2001-11-09 15:51 ` Ted Dennison
2001-11-10 0:47 ` Nick Roberts
2001-11-06 12:38 ` Roy Bell
2001-11-08 10:56 ` Ehud Lamm
2001-11-08 18:08 ` Roy Bell
2001-11-09 15:55 ` Ted Dennison
2001-11-09 16:15 ` Ehud Lamm
2001-11-09 17:37 ` Marin David Condic
2001-11-09 22:24 ` Ehud Lamm
2001-11-11 15:39 ` Marin David Condic
2001-11-10 2:35 ` Ted Dennison
2001-11-10 4:03 ` Jeffrey Carter
2001-11-11 21:09 ` Simon Wright
2001-11-12 5:33 ` Ted Dennison
2001-11-12 16:13 ` Jeffrey Carter
2001-11-13 7:11 ` Simon Wright
2001-11-11 15:45 ` Marin David Condic
2001-11-11 21:03 ` Simon Wright
2001-11-11 21:57 ` Ehud Lamm
2001-11-12 15:24 ` Marin David Condic
2001-11-13 7:06 ` Simon Wright
2001-11-13 21:21 ` Marin David Condic
2001-11-13 16:55 ` Stephen Leake
replies disabled
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox