220 9272 article Path: news.gmane.org!not-for-mail From: Matthew Woehlke Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: add "implicit" keyword? 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[80.91.229.3]) by mx.google.com with ESMTPS id ap10si10314168lac.80.2014.02.11.08.39.21 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Tue, 11 Feb 2014 08:39:21 -0800 (PST) Received-SPF: pass (google.com: domain of gclcip-std-proposals@m.gmane.org designates 80.91.229.3 as permitted sender) client-ip=80.91.229.3; Original-Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1WDGMj-000859-26 for std-proposals@isocpp.org; Tue, 11 Feb 2014 17:39:21 +0100 Original-Received: from tripoint.kitware.com ([66.194.253.20]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 11 Feb 2014 17:39:21 +0100 Original-Received: from mw_triad by tripoint.kitware.com with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 11 Feb 2014 17:39:21 +0100 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 29 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: tripoint.kitware.com User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 In-Reply-To: X-Original-Sender: mw_triad@users.sourceforge.net X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of gclcip-std-proposals@m.gmane.org designates 80.91.229.3 as permitted sender) smtp.mail=gclcip-std-proposals@m.gmane.org Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:9272 Archived-At: On 2014-02-11 01:19, David Krauss wrote: > Since implicit is always implicit, it can always be specified by lack > of specification. How would this achieve the desired goal? I admit I am not a compiler writer, but I expect most compilers have already run through preprocessing before the stage where a diagnostic for unmarked implicit methods could occur. > Fortunately, the preprocessor provides the user with the tools to > expressively specify nothing: > > #define implicit > > This is stylistically fine, completely portable, and easy to > understand (given a comment). It doesn't break anything except use of > implicit as an identifier, which the proposal does too. No, (as Thiago also points out) this is *far* worse than my proposal, which was to treat "implicit" as a keyword *only where it can be used as such*. Which are also, I believe, locations where already a type or identifier would be an error, which means that my proposal won't and can't break existing code. (Even code that already does e.g. like you propose, though of course the proposed diagnostic would not work in that case.) Whereas yours breaks any code that uses 'implicit' as a type and/or identifier. -- Matthew -- --- You received this message because you are subscribed to the Google Groups "ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an email to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. Visit this group at http://groups.google.com/a/isocpp.org/group/std-proposals/. .