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: 103376,703c4f68db81387d X-Google-Thread: 109fba,703c4f68db81387d X-Google-Thread: 115aec,703c4f68db81387d X-Google-Thread: f43e6,703c4f68db81387d X-Google-Attributes: gid103376,gid109fba,gid115aec,gidf43e6,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news1.google.com!proxad.net!newsfeed.stueberl.de!newsfeed01.sul.t-online.de!newsfeed00.sul.t-online.de!t-online.de!tsicnews.teliasonera.com!news.otenet.gr!news.grnet.gr!newsfd02.forthnet.gr!not-for-mail From: Ioannis Vranos Newsgroups: comp.lang.ada,comp.lang.c++,comp.realtime,comp.software-eng Subject: Re: [OT] Re: Teaching new tricks to an old dog (C++ -->Ada) Date: Mon, 14 Mar 2005 22:17:36 +0200 Organization: FORTHnet S.A., Atthidon 4, GR-17671 Kalithea, Greece, Tel: +30 2109559000, Fax: +30 2109559333, url: http://www.forthnet.gr Message-ID: <1110831454.873061@athnrd02> References: <4229bad9$0$1019$afc38c87@news.optusnet.com.au> <1110032222.447846.167060@g14g2000cwa.googlegroups.com> <871xau9nlh.fsf@insalien.org> <3SjWd.103128$Vf.3969241@news000.worldonline.dk> <87r7iu85lf.fsf@insalien.org> <1110052142.832650@athnrd02> <42309456$1@news.broadpark.no> <4232ab3a$0$26547$9b4e6d93@newsread4.arcor-online.net> <1110825790.396769@athnrd02> NNTP-Posting-Host: athnrd02.forthnet.gr Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Trace: athprx02.forthnet.gr 1110831460 5479 193.92.150.73 (14 Mar 2005 20:17:40 GMT) X-Complaints-To: abuse@forthnet.gr NNTP-Posting-Date: Mon, 14 Mar 2005 20:17:40 +0000 (UTC) User-Agent: Mozilla Thunderbird 1.0 (Windows/20041206) X-Accept-Language: en-us, en In-Reply-To: Cache-Post-Path: newsfd02!unknown@ppp29-adsl-227.ath.forthnet.gr Xref: g2news1.google.com comp.lang.ada:9383 comp.lang.c++:45648 comp.realtime:1464 comp.software-eng:5031 Date: 2005-03-14T22:17:36+02:00 List-Id: Dr. Adrian Wrigley wrote: > The comparison operator here seems to be a generic formal function > parameter with a default value. This must be available at instantiation. > The operator becomes part of the interface (implicitly or explicitly) for > any code instantiating the std::map. Where does the code for the > comparison operator go? It *has* to go at the point the class > is defined. Yes. However if you later convert to a hash container, it can remain around unused in the particular container. > This could be at the other end of a hierarchy of > generic instantiations. The result is that the implementation > requirement (needs a comparison operator) has propagated up the > generic hierarchy to some otherwise completely independent code as an > interface requirement. I'm sorry I can't explain this any better! > (should I give a code example?) Yes, also operator< is used to all containers and algorithms where a comparison takes place, like sorting algorithms (std::sort, std::stable_sort, etc). I can not understand how this could be avoided for such operations and containers, since a comparison is required. -- Ioannis Vranos http://www23.brinkster.com/noicys