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: 103376,55f6e230b02eff2f X-Google-Attributes: gid103376,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news2.google.com!postnews.google.com!k79g2000hse.googlegroups.com!not-for-mail From: Maciej Sobczak Newsgroups: comp.lang.ada Subject: Re: Containers - nontrivial element access Date: Tue, 02 Oct 2007 14:02:19 -0700 Organization: http://groups.google.com Message-ID: <1191358939.031798.177670@k79g2000hse.googlegroups.com> References: <1191275759.184463.238350@n39g2000hsh.googlegroups.com> <1191343071.685478.146710@19g2000hsx.googlegroups.com> NNTP-Posting-Host: 85.3.68.29 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" X-Trace: posting.google.com 1191358939 2159 127.0.0.1 (2 Oct 2007 21:02:19 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Tue, 2 Oct 2007 21:02:19 +0000 (UTC) In-Reply-To: <1191343071.685478.146710@19g2000hsx.googlegroups.com> User-Agent: G2/1.0 X-HTTP-UserAgent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en-US; rv:1.8.1.7) Gecko/20070914 Firefox/2.0.0.7,gzip(gfe),gzip(gfe) Complaints-To: groups-abuse@google.com Injection-Info: k79g2000hse.googlegroups.com; posting-host=85.3.68.29; posting-account=ps2QrAMAAAA6_jCuRt2JEIpn5Otqf_w0 Xref: g2news2.google.com comp.lang.ada:2255 Date: 2007-10-02T14:02:19-07:00 List-Id: On 2 Pa , 18:37, Matthew Heaney wrote: > V : Person_Vectors.Vector; > > declare > procedure Process_X (PX : in out Person) is > procedure Process_Y (PY : in out Person) is > SX : constant Salary_Type := PX.Salary; > begin > PX.Salary := PY.Salary; > PY.Salary := SX; > end; > begin > V.Update_Element (Y, Process_Y'Access); > end; > begin > V.Update_Element (X, Process_X'Access); > end; I have mixed feelings about this example. I like it, because it solves the problem without requiring any additional variable. I don't like it, because it imposes some artificial assymetry (one of the procedures has to be nested) where the problem is strictly symmetrical. OK, this assymetry stuff is nit-picking. I accept this as a valid solution, even though it is not even close in readability to my initial C++ example. BTW - above, PX plays the role of that additional variable that is sneaked around to the second procedure. Here it just pretends to not exist by taking the form of a parameter in the outer procedure. I don't think there is a reasonable way to avoid it. -- Maciej Sobczak * www.msobczak.com * www.inspirel.com