From -6406893598990051224 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f78e5,307cbe6f0ea2ccd3 X-Google-Attributes: gidf78e5,public X-Google-ArrivalTime: 2003-06-11 12:24:40 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!kibo.news.demon.net!mutlu.news.demon.net!demon!mail2news.demon.co.uk!devnull From: ark@research.att.com (Andrew Koenig) Newsgroups: comp.std.c++ Subject: Re: Recommendation to the Standards Committee Date: Wed, 11 Jun 2003 19:24:39 +0000 (UTC) Organization: AT&T Shannon Laboratory, Florham Park, NJ Lines: 29 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=us-ascii X-Trace: mail2news.demon.co.uk 1055359479 28709 10.0.0.1 (11 Jun 2003 19:24:39 GMT) X-Complaints-To: abuse@demon.net NNTP-Posting-Date: Wed, 11 Jun 2003 19:24:39 +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 19QBD4-0007Su-00 for mail2news@news.news.demon.net; Wed, 11 Jun 2003 19:24:39 +0000 X-Received: from localhost (localhost [[UNIX: localhost]]) by mulga.cs.mu.OZ.AU id FAA17103; Thu, 12 Jun 2003 05:24:35 +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-Newsgroups: comp.std.c++ X-Nntp-Posting-Host: europa.research.att.com X-User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 X-Spam-Status: No, hits=-6.6 required=5.0 tests=NOSPAM_INC,REFERENCES,SIGNATURE_SHORT_DENSE, SPAM_PHRASE_00_01,UNDISC_RECIPS,USER_AGENT version=2.41 Xref: archiver1.google.com comp.std.c++:19693 Francis> Being able to write: Francis> #once Francis> at the start of a header file would solve the problem because Francis> compilers would then read the file the first time, mark it as Francis> read in its tables and not try to read it again. There are already compilers that detect header files of the form #ifndef anything #endif (and similarly for #ifdef), and decline to process the file a second time if is set (or unset) when the file is included a second time. For such compilers, no special directives are needed. -- Andrew Koenig, ark@research.att.com, http://www.research.att.com/info/ark --- [ 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 ]