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=-0.9 required=5.0 tests=BAYES_00,FORGED_GMAIL_RCVD,
	FREEMAIL_FROM autolearn=no autolearn_force=no version=3.4.4
X-Google-Thread: 103376,5c89acd494ea9116,start
X-Google-Attributes: gid103376,public,usenet
X-Google-Language: ENGLISH,ASCII-7-bit
Path: 
 g2news1.google.com!postnews.google.com!n60g2000hse.googlegroups.com!not-for-mail
From: Maciej Sobczak <see.my.homepage@gmail.com>
Newsgroups: comp.lang.ada
Subject: Self pointer in limited record
Date: Wed, 04 Jul 2007 12:31:08 -0700
Organization: http://groups.google.com
Message-ID: <1183577468.034566.57830@n60g2000hse.googlegroups.com>
NNTP-Posting-Host: 85.3.225.229
Mime-Version: 1.0
Content-Type: text/plain; charset="iso-8859-1"
X-Trace: posting.google.com 1183577468 21242 127.0.0.1 (4 Jul 2007 19:31:08
 GMT)
X-Complaints-To: groups-abuse@google.com
NNTP-Posting-Date: Wed, 4 Jul 2007 19:31:08 +0000 (UTC)
User-Agent: G2/1.0
X-HTTP-UserAgent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en-US;
 rv:1.8.1.4) Gecko/20070515 Firefox/2.0.0.4,gzip(gfe),gzip(gfe)
Complaints-To: groups-abuse@google.com
Injection-Info: n60g2000hse.googlegroups.com; posting-host=85.3.225.229;
   posting-account=Ch8E9Q0AAAA7lJxCsphg7hBNIsMsP4AE
Xref: g2news1.google.com comp.lang.ada:16414
Date: 2007-07-04T12:31:08-07:00
List-Id: <comp.lang.ada>

Consider:

type T_Access is access all T;
type T is  new Ada.Finalization.Limited_Controlled with record
   Self : T_Access := T'Unchecked_Access;
   -- more components
   -- ...
end record;

I have seen this pattern repeatedly. What is the use for Self?
And why is it Unchecked?

--
Maciej Sobczak
http://www.msobczak.com/