From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00
	autolearn=unavailable autolearn_force=no version=3.4.4
Path: 
 border1.nntp.ams.giganews.com!nntp.giganews.com!eternal-september.org!feeder.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From: Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Generics vs. O-O?
Date: Fri, 02 Aug 2013 10:00:30 -0700
Organization: Also freenews.netfront.net; news.tornevall.net
Message-ID: <ktgo74$80h$1@dont-email.me>
References: <6238c325-79c5-4537-ba55-2800110dc6df@googlegroups.com>
 <1wugpqyea6s39$.e2e8eshup5wn$.dlg@40tude.net>
 <51fadf40$0$6557$9b4e6d93@newsspool4.arcor-online.net>
 <15qso6tlt3uf1.h45wqc019b00$.dlg@40tude.net>
 <51fb80d8$0$6561$9b4e6d93@newsspool4.arcor-online.net>
 <1so729qnkrrj2.ztrxvmlw6cb7.dlg@40tude.net>
 <8bef1dc4-547b-478e-b81a-09077212f821@googlegroups.com>
 <d474202c-4cee-49ef-9f93-9bf9ee6a89a6@googlegroups.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Injection-Date: Fri, 2 Aug 2013 16:53:58 +0000 (UTC)
Injection-Info: mx05.eternal-september.org;
 posting-host="194df0738b6f7da39154e0dc362e454f";
 logging-data="8209"; mail-complaints-to="abuse@eternal-september.org";
 posting-account="U2FsdGVkX189anH3SJHjJEo5kCC2NOC9vyNfv4naNtw="
User-Agent: Mozilla/5.0 (X11; Linux x86_64;
 rv:17.0) Gecko/17.0 Thunderbird/17.0
In-Reply-To: <d474202c-4cee-49ef-9f93-9bf9ee6a89a6@googlegroups.com>
Cancel-Lock: sha1:MfGUbWK/22PdXcVLn+68UBe8CCw=
Xref: number.nntp.dca.giganews.com comp.lang.ada:182819
Date: 2013-08-02T10:00:30-07:00
List-Id: <comp.lang.ada>

On 08/02/2013 08:36 AM, Alan Jump wrote:
>
> This is going off on a bit of a tangent, but as a new student of the
> language, I  think a case could be made that many stand-alone packages or
> procedures in Ada are singletons, simply because of Ada's inherent strong
> typing. After all, what's a singleton? By definition, to be a singleton
> pattern, two criteria must be met: one and only one instance with a global
> point of access, and initialization on first use. (Source:
> http://sourcemaking.com/design_patterns/singleton)

Right. The "singleton type" is a kludge from languages that confuse the concepts 
of type and module. In Ada, which properly separates these concepts, a singleton 
is simply a package.

-- 
Jeff Carter
"You me on the head hitted."
Never Give a Sucker an Even Break
108