From 2597784065370276359 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f78e5,307cbe6f0ea2ccd3 X-Google-Attributes: gidf78e5,public X-Google-ArrivalTime: 2003-06-10 11:22:49 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!newsfeed.icl.net!newsfeed.fjserv.net!proxad.net!proxad.net!kibo.news.demon.net!mutlu.news.demon.net!demon!mail2news.demon.co.uk!devnull From: m@rtij.nl.removefromhere.invalid (Martijn Lievaart) Newsgroups: comp.std.c++ Subject: Re: Recommendation to the Standards Committee Date: Tue, 10 Jun 2003 18:22:49 +0000 (UTC) Organization: TINO Lines: 28 Approved: fjh@cs.mu.oz.au (Fergus Henderson , moderator of comp.std.c++) Message-ID: References: <_ULEa.10852$KF1.271850@amstwist00> <3EE50908.9060202@hotmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: mail2news.demon.co.uk 1055269369 22938 10.0.0.1 (10 Jun 2003 18:22:49 GMT) X-Complaints-To: abuse@demon.net NNTP-Posting-Date: Tue, 10 Jun 2003 18:22:49 +0000 (UTC) X-Received: from mulga.cs.mu.oz.au ([128.250.1.22]) by news.demon.co.uk with esmtp (Exim 4.12) id 19Pnlf-0005xo-00 for mail2news@news.news.demon.net; Tue, 10 Jun 2003 18:22:48 +0000 X-Received: from localhost (localhost [[UNIX: localhost]]) by mulga.cs.mu.OZ.AU id EAA04723; Wed, 11 Jun 2003 04:22:34 +1000 (EST) X-Authentication-Warning: mulga.cs.mu.OZ.AU: fjh set sender to devnull@stump.algebra.com using -f X-Path: comp-std-cpp-robomod!not-for-mail X-Robomod: STUMP, ichudov@algebra.com (Igor Chudov) X-Delivered-To: std-c++@ucar.edu X-User-Agent: Pan/0.14.0 (I'm Being Nibbled to Death by Cats!) X-Newsgroups: comp.std.c++ X-Spam-Status: No, hits=-7.6 required=5.0 tests=EMAIL_ATTRIBUTION,NOSPAM_INC,QUOTED_EMAIL_TEXT,REFERENCES, SATISFACTION,SPAM_PHRASE_00_01,USER_AGENT version=2.41 Xref: archiver1.google.com comp.std.c++:19673 On Mon, 09 Jun 2003 23:05:51 +0000, Andrey Tarasevich wrote: [ #once ] > > Yeah, but it looks like the main point of the method Brian is using is that > the guarding '#ifndef'/'#endif' is placed _outside_ the header file. In this > case the preprocessor doesn't even have to search for already included > files, open them or try parsing them. The '#once' solution doesn't help in > this case, since '#once' directive is supposed to be specified _inside_ > header files. From this respect '#once' is not much different from the > standard "internal '#ifndef'/'#define'/'#endif' approach". But it looks > like Brian is not satisfied with the latter. Under this circumstances, I > don't think he will be satisfied with any other "internal" solution. I don't think so. The compiler can 'cache' the #once and skip the header when the #include directive is seen again. Hmmmm, as a QoI issue, a compiler /could/ recognize header guards and treat the as #once.... Hmmmm. M4 --- [ 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.jamesd.demon.co.uk/csc/faq.html ]