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=ham
	autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103376,56131a5c3acc678e
X-Google-Attributes: gid103376,public
X-Google-ArrivalTime: 2003-12-01 13:13:13 PST
Path: 
 archiver1.google.com!news2.google.com!news.maxwell.syr.edu!elnk-pas-nf1!newsfeed.earthlink.net!stamper.news.pas.earthlink.net!newsread2.news.pas.earthlink.net.POSTED!a6202946!not-for-mail
From: Jeffrey Carter <spam@spam.com>
Organization: jrcarter commercial-at acm [period | full stop] org
User-Agent: Mozilla/5.0 (Windows; U; Win98; en-US; rv:1.4) Gecko/20030624
X-Accept-Language: en-us, en
MIME-Version: 1.0
Newsgroups: comp.lang.ada
Subject: Re: Question about OO programming in Ada
References: <bq092s$9ph$1@online.de> <uhe0sqfud.fsf@nasa.gov>
 <bq0qfs$3ja$1@online.de> <GpednY19wYJAdFmiRVn-gg@comcast.com>
 <bq3mef$49e$1@online.de>
 <8urxb.19482$sb4.18182@newsread2.news.pas.earthlink.net>
 <ygAxb.8265$lF6.7551@nwrdny01.gnilink.net>
 <1792884.HtYz4Yv8lY@linux1.krischik.com>
In-Reply-To: <1792884.HtYz4Yv8lY@linux1.krischik.com>
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Message-ID: <I9Oyb.23785$sb4.2675@newsread2.news.pas.earthlink.net>
Date: Mon, 01 Dec 2003 21:13:12 GMT
NNTP-Posting-Host: 63.184.33.225
X-Complaints-To: abuse@earthlink.net
X-Trace: newsread2.news.pas.earthlink.net 1070313192 63.184.33.225 (Mon,
 01 Dec 2003 13:13:12 PST)
NNTP-Posting-Date: Mon, 01 Dec 2003 13:13:12 PST
Xref: archiver1.google.com comp.lang.ada:3058
Date: 2003-12-01T21:13:12+00:00
List-Id: <comp.lang.ada>

Martin Krischik wrote:

> Hyman Rosen wrote:
> 
> 
>>Jeffrey Carter wrote:
>> > you cannot create a dangling reference with 'Access.
>>
>>How not? Just deallocate the object to which the pointer points.
> 
> 
> How will you do this without using some form of "Unchecked_"?

'access creates an access value to something that is not allocated by 
the programmer on the heap, so it cannot be deallocated:

declare
    type Integer_Ptr is access all Integer;

    I : aliased Integer;
    P : Integer_Ptr := I'access;
begin
    null;
end;

You cannot deallocate I (except by leaving its scope).

-- 
Jeff Carter
"In the frozen land of Nador they were forced to
eat Robin's minstrels, and there was much rejoicing."
Monty Python & the Holy Grail
70