220 9275 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 n3si10369870lae.124.2014.02.11.09.05.05 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Tue, 11 Feb 2014 09:05:05 -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 1WDGlb-0001BB-VZ for std-proposals@isocpp.org; Tue, 11 Feb 2014 18:05:03 +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 18:05:03 +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 18:05:03 +0100 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 32 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: <20140211065430.GA4771@faust.lysator.liu.se> 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:9275 Archived-At: On 2014-02-11 01:54, Magnus Fromreide wrote: > On Mon, Feb 10, 2014 at 11:30:32AM -0500, Matthew Woehlke wrote: >> Objective: >> ---------- >> Create a new keyword "implicit", having the meaning 'not >> "explicit"'. That is, this keyword would annotate that a constructor >> or conversion operator is allowed to be called in a manner that >> would be denied by 'explicit'. > > I would expect a constructor marked as 'implicit' to be disallowed > in explicit situations, so > > struct foo { > implicit foo(int) { } > }; > > foo f = 1; // Valid > foo g(1); // Invalid > > but I admit to not seeing much value in it. Yes, that seems like it would be very confusing, besides that it is a new behavior (which my proposal wouldn't be). > As for the bikeshed, both 'not' and 'explicit' are already keywords, so why > not spell it 'not explicit'? I could (with a '#define implicit not explicit', probably :-) ) live with that. -- 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. 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