From -1270717889612805118 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f78e5,df0f8d484c0311f9 X-Google-Attributes: gidf78e5,public Path: controlnews3.google.com!news1.google.com!news.glorb.com!newsrout1.ntli.net!news-in.ntli.net!kibo.news.demon.net!mutlu.news.demon.net!demon!mail2news.demon.co.uk!devnull From: meang@post.com (Meang Akira Tanaka) Newsgroups: comp.std.c++ Subject: Re: Proposal for default values when declaring the class Date: Sat, 1 May 2004 16:51:24 +0000 (UTC) Organization: UNI2 Internet Kunde Lines: 55 Approved: fjh@cs.mu.oz.au (Fergus Henderson , moderator of comp.std.c++) Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: mail2news.demon.co.uk 1083430284 6640 10.0.0.1 (1 May 2004 16:51:24 GMT) X-Complaints-To: abuse@demon.net NNTP-Posting-Date: Sat, 1 May 2004 16:51:24 +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 1BJxhz-0001ix-00 for mail2news@news.news.demon.net; Sat, 01 May 2004 16:51:24 +0000 X-Received: from mulga.cs.mu.OZ.AU (localhost [127.0.0.1]) by mulga.cs.mu.OZ.AU with ESMTP id i41GpMi2013201; Sun, 2 May 2004 02:51:22 +1000 (EST) X-Received: (from fjh@localhost) by mulga.cs.mu.OZ.AU (8.12.10+Sun/8.12.9/Submit) id i41GpLWe013192; Sun, 2 May 2004 02:51:21 +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-Newsreader: Forte Agent 1.93/32.576 English (American) X-NNTP-Posting-Date: Fri, 30 Apr 2004 22:15:04 CEST X-Spam-Checker-Version: SpamAssassin 2.60-mulga_r1 (1.212-2003-09-23-exp) on mulga.cs.mu.OZ.AU X-Spam-Status: No, hits=0.0 required=5.2 tests=none autolearn=no version=2.60-mulga_r1 Xref: controlnews3.google.com comp.std.c++:65 On Fri, 30 Apr 2004 15:04:49 +0000 (UTC), francis@robinton.demon.co.uk (Francis Glassborow) wrote: <*snip*> >Using forwarding ctors the above becomes: > >class foo { > int var1; > bool var2; > char var3; >public: > foo(int v1 = 100, bool v2 = true, char v3 = 'a'); > // that covers your first two ctors > foo(bool v2) : foo(105, v2){} > > > >This change (forwarding ctors) does not quite do what you were proposing >but it is much simpler to incorporate into the language and simpler for >the implementors to implement. It has it charms... and definitly better than nothing, but I think it isn't as clear as the one I proposed... how are the arguments mapped? It isn't clear from the variable names you used v1, v2 etc.. or did you mean var1 = 100, var2 = true etc... if that is not the case how do you know which variable should be mapped to which attribute? class foo { int var1; int var2; int var3; public: foo(int v1 = 100, bool v2 = 105, char v3 = 107 ); } but I am definitly looking forward to compilers who will support it... br Meang --- [ 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 ]