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=-2.9 required=5.0 tests=BAYES_00,MAILING_LIST_MULTI autolearn=unavailable autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,a00006d3c4735d70 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2004-01-26 17:17:30 PST Path: archiver1.google.com!news2.google.com!news.maxwell.syr.edu!newsfeed.icl.net!newsfeed.fjserv.net!newsfeed.icl.net!newsfeed.fjserv.net!proxad.net!freenix!enst.fr!melchior!cuivre.fr.eu.org!melchior.frmug.org!not-for-mail From: "Alexandre E. Kopilovitch" Newsgroups: comp.lang.ada Subject: Re: In-Out Parameters for functions Date: Tue, 27 Jan 2004 04:12:21 +0300 (MSK) Organization: Cuivre, Argent, Or Message-ID: References: NNTP-Posting-Host: lovelace.ada-france.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: melchior.cuivre.fr.eu.org 1075165908 69804 80.67.180.195 (27 Jan 2004 01:11:48 GMT) X-Complaints-To: usenet@melchior.cuivre.fr.eu.org NNTP-Posting-Date: Tue, 27 Jan 2004 01:11:48 +0000 (UTC) To: comp.lang.ada@ada-france.org Return-Path: In-Reply-To: ; from Robert A Duff at 26 Jan 2004 18:12:47 -0500 X-Mailer: Mail/@ [v2.44 MSDOS] X-Virus-Scanned: by amavisd-new-20030616-p5 (Debian) at ada-france.org X-BeenThere: comp.lang.ada@ada-france.org X-Mailman-Version: 2.1.3 Precedence: list List-Id: Gateway to the comp.lang.ada Usenet newsgroup List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Xref: archiver1.google.com comp.lang.ada:4863 Date: 2004-01-27T04:12:21+03:00 Robert A Duff wrote: > If at least one parameter of a function is in IN OUT mode then the function > cannot be used in a compound expression. This function's call must always > constitute the whole RHS of an assignment. > > But this allows: > > A(I) := F(I); > > where A is an array, and F modifies its parameter I. Yes, you are certainly right, and I overlooked this standard trap (well-known from Algol-60 times). But nevertheless I think that in this particular context - when we are talking about the difference between changing global variables and IN OUT parameters, this counter-example is not valid - I think that there is no significant difference between using global variable as index and that in the example. Alexander Kopilovitch aek@vib.usr.pu.ru Saint-Petersburg Russia