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: 
 eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!eu.feeder.erje.net!feeder.erje.net!us.feeder.erje.net!xmission!newsswitch.lcs.mit.edu!nntp.TheWorld.com!.POSTED!not-for-mail
From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Dereferencing and style guides
Date: Mon, 30 Sep 2013 08:51:32 -0400
Organization: The World Public Access UNIX, Brookline, MA
Message-ID: <wcczjquzd4b.fsf@shell01.TheWorld.com>
References: <slrnl4i6sh.1lme.lithiumcat@sigil.instinctive.eu>
NNTP-Posting-Host: shell01.theworld.com
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
X-Trace: pcls7.std.com 1380545492 22549 192.74.137.71 (30 Sep 2013 12:51:32
 GMT)
X-Complaints-To: abuse@TheWorld.com
NNTP-Posting-Date: Mon, 30 Sep 2013 12:51:32 +0000 (UTC)
User-Agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/21.3 (irix)
Cancel-Lock: sha1:77U5U+FFwzucNSGZWLgUawWitc0=
Xref: news.eternal-september.org comp.lang.ada:17353
Date: 2013-09-30T08:51:32-04:00
List-Id: <comp.lang.ada>

Natasha Kerensikova <lithiumcat@gmail.com> writes:

> I think somehow I like to have my statements as context-free as
> possible. So when I see Some_Variable.all I don't have to remember that
> Some_Variable is actually an access value rather than a full-fledged
> object.

I agree with you that dereferencing should be explicit.  Aliasing is
dangerous.  It's good to have a reminder, "There might be other things
pointing at this thing."  If dereference had a decent syntax,
like "^" in Pascal, I would use it always.  And I think the language
should require that.  (A pure functional language is different!)

However, the ".all" syntax is just plain weird.  "All what?"  It makes
no sense to me.  And it's too verbose (should be a single character).
So I don't use it, except when it's required, or in rare cases where I
think it's very important to emphasize the aliasing issue.

There's an option in GNAT to get it to complain when you
leave out ".all".  A pragma-Restriction, I think.

- Bob