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-Thread: a07f3367d7,5d624451bcaff335
X-Google-Attributes: gida07f3367d7,public,usenet
X-Google-NewGroupId: yes
X-Google-Language: ENGLISH,CP1252
Path: 
 g2news2.google.com!postnews.google.com!j9g2000prh.googlegroups.com!not-for-mail
From: Adam Beneschan <adam@irvine.com>
Newsgroups: comp.lang.ada
Subject: Re: Null Range in Unconstrasined Array
Date: Tue, 1 Sep 2009 07:50:48 -0700 (PDT)
Organization: http://groups.google.com
Message-ID: <76a9c14b-c573-4fd4-bbd8-7ab3bd078d79@j9g2000prh.googlegroups.com>
References: 
 <f237670b-ade0-461f-9d02-5eff803e91bc@p10g2000prm.googlegroups.com>
NNTP-Posting-Host: 66.126.103.122
Mime-Version: 1.0
Content-Type: text/plain; charset=windows-1252
Content-Transfer-Encoding: quoted-printable
X-Trace: posting.google.com 1251816648 19744 127.0.0.1 (1 Sep 2009 14:50:48
 GMT)
X-Complaints-To: groups-abuse@google.com
NNTP-Posting-Date: Tue, 1 Sep 2009 14:50:48 +0000 (UTC)
Complaints-To: groups-abuse@google.com
Injection-Info: j9g2000prh.googlegroups.com; posting-host=66.126.103.122;
	posting-account=duW0ogkAAABjRdnxgLGXDfna0Gc6XqmQ
User-Agent: G2/1.0
X-HTTP-UserAgent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; WOW64;
	SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.5.21022; .NET CLR
	3.5.30729; .NET CLR 3.0.30618),gzip(gfe),gzip(gfe)
Xref: g2news2.google.com comp.lang.ada:8101
Date: 2009-09-01T07:50:48-07:00
List-Id: <comp.lang.ada>

On Aug 31, 6:28=A0pm, Rick <rickdu...@gmail.com> wrote:
> If I have an unconstrained array type 'My_Array_Type' and declare an
> instance of it as:
>
> My_Array : My_Array_Type (1 .. 0);
>
> then the LRM tells me it is a null range:
>
> 3.5 (4): A range with lower bound L and upper bound R is described by
> =93L .. R=94. If R is less than L, then the range is a null range, and
> specifies an empty set of values.
>
> What, exactly, is My_Array (forgive the language) pointing to?
> Is any memory allocated to My_Array?

Most likely, no.  Randy gave a reason why a compiler might want to
allocate a little bit of space for the array; but even if it does,
it's memory that will never be used.  Any attempt to refer to My_Array
(X), no matter what X is, will raise Constraint_Error.

                                    -- Adam