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.ams3.giganews.com!border2.nntp.ams3.giganews.com!border2.nntp.ams2.giganews.com!border4.nntp.ams.giganews.com!border2.nntp.ams.giganews.com!nntp.giganews.com!de-l.enfer-du-nord.net!feeder2.enfer-du-nord.net!feeder.erje.net!eu.feeder.erje.net!news-1.dfn.de!news.dfn.de!news.uni-weimar.de!medsec1.medien.uni-weimar.de!lucks
From: Stefan.Lucks@uni-weimar.de
Newsgroups: comp.lang.ada
Subject: Re: Gnat 2013 is out!
Date: Fri, 31 May 2013 13:30:12 +0200
Organization: Bauhaus-Universitaet Weimar
Message-ID: <alpine.DEB.2.02.1305311319150.13043@debian>
References: <ko500n$a4v$1@dont-email.me> <lyhahl96b5.fsf@pushface.org>
 <lyd2s99324.fsf@pushface.org> <ko603g$dde$1@loke.gir.dk>
 <32d94173-533a-471e-95a0-abb73a6cdcc2@googlegroups.com>
 <ko8ao8$55i$1@loke.gir.dk>
NNTP-Posting-Host: medsec1.medien.uni-weimar.de
Mime-Version: 1.0
Content-Type: MULTIPART/MIXED; BOUNDARY="8323329-68110572-1369999815=:13043"
X-Trace: tigger.scc.uni-weimar.de 1369999981 24149 141.54.178.228 (31 May 2013
 11:33:01 GMT)
X-Complaints-To: news@tigger.scc.uni-weimar.de
NNTP-Posting-Date: Fri, 31 May 2013 11:33:01 +0000 (UTC)
X-X-Sender: lucks@debian
In-Reply-To: <ko8ao8$55i$1@loke.gir.dk>
User-Agent: Alpine 2.02 (DEB 1266 2009-07-14)
X-Original-Bytes: 3303
Xref: number.nntp.dca.giganews.com comp.lang.ada:181776
Date: 2013-05-31T13:30:12+02:00
List-Id: <comp.lang.ada>

  This message is in MIME format.  The first part should be readable text,
  while the remaining parts are likely unreadable without MIME-aware tools.

--8323329-68110572-1369999815=:13043
Content-Type: TEXT/PLAIN; charset=ISO-8859-15; format=flowed
Content-Transfer-Encoding: QUOTED-PRINTABLE

On Thu, 30 May 2013, Randy Brukardt wrote:

> "Adam Beneschan" <adam@irvine.com> wrote in message
>
>> I've always wanted some kind of feature in Ada that would allow a=20
>> caller to provide a "dummy" for OUT parameters, without having to=20
>> declare a new variable.  The compiler would allocate a temporary object=
=20
>> (and a separate one for each use of a "dummy") and then discard it=20
>> after the call.  It wouldn't work well when parameter types are=20
>> unconstrained array or discriminant records, though.
>
> Hmm, that seems like a good idea to me. But what would the syntax be? <>
> maybe?
>
>         My_Proc (Obj1, Obj2, Result =3D> <>);
>

This has two issues:

   1. This won't work if the type of Result is unconstrained, as, e.g., in

      procedure My_Proc(Obj1, Obj2: String; Result : String);

   2. This would sometimes break overload resolution -- which procedure
      should be called by "My_Proc (Obj1, Obj2, Result =3D> <>);" if there
      happens to be another procedure in scope, such as

      procedure My_Proc(Obj1, Obj2: String; Result : Unbounded_String);

I'd suggest


         My_Proc (Obj1, Obj2, Result =3D> String(1 .. 80));

or in general

         My_Proc (Obj1, Obj2, Result =3D> type Name_of_Type);

as syntactic sugar for

    declare
      Dummy : Name_Of_Type;
    begin
      My_Proc (Obj1, Obj2, Result =3D> type Name_of_Type);
    end;





------  I  love  the  taste  of  Cryptanalysis  in  the morning!  ------
     <http://www.uni-weimar.de/cms/medien/mediensicherheit/home.html>
--Stefan.Lucks (at) uni-weimar.de, Bauhaus-Universit=E4t Weimar, Germany--

--8323329-68110572-1369999815=:13043--