From -6416486990678263899 X-Google-Language: ENGLISH,ASCII X-Google-Thread: f78e5,ccbfcafab96cf493 X-Google-Attributes: gidf78e5,public X-Google-ArrivalTime: 2001-11-27 09:48:01 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!newsfeed.gamma.ru!Gamma.RU!dispose.news.demon.net!news.demon.co.uk!demon!mail2news.demon.co.uk!not-for-mail From: Francis Glassborow Newsgroups: comp.std.c++ Subject: Re: Proposol to increase robustness of programs Date: Tue, 27 Nov 2001 17:47:06 GMT Organization: Southfield Microcomputer SS Approved: Fergus Henderson , moderator of comp.std.c++ Message-ID: References: <3BFE97B3.91430FB1@wanadoo.fr> <3C02E8F1.4BDAAF29@acm.org> Reply-To: Francis Glassborow X-Trace: mail2news.demon.co.uk 1006883231 mail2news:28523 mail2news mail2news.demon.co.uk X-Complaints-To: abuse@demon.net X-Mail2News-Path: news.demon.net!mulga.cs.mu.oz.au X-Authentication-Warning: mulga.cs.mu.OZ.AU: fjh set sender to devnull@stump.algebra.com using -f X-Robomod: STUMP, ichudov@algebra.com (Igor Chudov) MIME-Version: 1.0 Content-Type: text/plain;charset=iso-8859-1;format=flowed User-Agent: Turnpike/6.00-U () Content-Transfer-Encoding: quoted-printable X-MIME-Autoconverted: from 8bit to quoted-printable by mulga.cs.mu.OZ.AU id EAA27597 Lines: 42 Xref: archiver1.google.com comp.std.c++:8318 In article <3C02E8F1.4BDAAF29@acm.org>, Pete Becker =20 writes >Lo=EFc Joly wrote: >> >> This works just fine, but now, suppose someone in charge of maintainin= g >> the A class discovers that the declaration of f should have been : >> virtual void f(char const *s); >> He makes the change, but somehow forget to change class B. The compile= r >> will compile silently, but the program will not do the expected thing. >> This is a real-world example that has already bitten me several times, >> and is difficult to debug. >> > >You should complain to the person who made that change without >understanding and documenting its implications. Adding a virtual >function to a class (whether that's a consequence of adding a new >function or changing an existing one) is a drastic change, and users of >the class should be alerted to it. You mean like the way that the Standard encourages implementors to tell=20 users about adding parameters to functions (thereby changing their=20 signatures, and possibly altering overload resolution when assigning to=20 a pointer to member? :-) Unfortunately we live in a far from perfect world. It is a good idea to=20 check that the cars have actually stopped before stepping onto a=20 pedestrian crossing. --=20 Francis Glassborow I offer my sympathy and prayers to all those who are suffering as a result of the events of September 11 2001. --- [ comp.std.c++ is moderated. To submit articles, try just posting with ] [ your news-reader. If that fails, use mailto:std-c++@ncar.ucar.edu ] [ --- Please see the FAQ before posting. --- ] [ FAQ: http://www.research.att.com/~austern/csc/faq.html ]