220 15372 article Path: news.gmane.org!not-for-mail From: Olaf van der Spek Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Isn't it time we had the bool std::[container]::contains() family of methods? Date: Mon, 29 Dec 2014 20:35:40 +0100 Lines: 42 Approved: news@gmane.org Message-ID: References: <0959f2f8-acdd-4786-b6f3-0f05c62dcee6@isocpp.org> <1467325.0dEsDvEnHx@tjmaciei-mobl4> <3990670.unDteUsXEa@tjmaciei-mobl4> <232a2f25-0907-48e5-ba04-e1d9b09e19e7@isocpp.org> <34298b73-1e10-4efa-8527-e1caf84c719c@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Trace: ger.gmane.org 1419881753 21977 80.91.229.3 (29 Dec 2014 19:35:53 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 29 Dec 2014 19:35:53 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBC5NB45SSABBBDO2Q2SQKGQEQWBBHRA@isocpp.org Mon Dec 29 20:35:46 2014 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-oi0-f72.google.com ([209.85.218.72]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Y5g6R-0005sO-Az for gclcip-std-proposals@m.gmane.org; Mon, 29 Dec 2014 20:35:43 +0100 Original-Received: by mail-oi0-f72.google.com with SMTP id e131sf243534367oig.3 for ; Mon, 29 Dec 2014 11:35:42 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:content-type:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:list-post:list-help:list-archive:list-subscribe :list-unsubscribe; bh=FcAGpNanz2/UQLmnh2agRA+9vLZDnJO28izFdr7ki/s=; b=ZggqpwxSmNCjSoO/K/zgAiKabQ+DJ2bwlhR/jzJjcuvDlzDefVyaCuK+JyjPFuaaqC 40ZRdNU5uwfhngtqI3Dmlc2GHGGd0Gq7U1X6Jmka26S6fIj0lzMyP1AM4F29XzMUqwLy wR2N23p8U7fzOfOU2VABNsl5o2bsbDfEUwzC2m3OILwTRHmbiHPlTSgNVGNMeTkbuGrS AE0zVpE7b1/68yjJOVF9uKzd5FjoR9TA0kGE0XMsrzZVN2jeqMteZL8Rr4B8cWtBnTUt mC10YlVHiOWTRRKKawzbJ1yP0w9p9OY/fQPXUUUO92IQOoA8ibewgNNvlSN7gjxcMkvH Vx/w== X-Gm-Message-State: ALoCoQnnQ9WUmzFbB+rTNuPBhg4/I6byNS9LHIHXgJHGaLfzd1AWfcctkkNoB01UBC5gcx14eX/K X-Received: by 10.182.29.39 with SMTP id g7mr42292803obh.36.1419881742144; Mon, 29 Dec 2014 11:35:42 -0800 (PST) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.140.94.118 with SMTP id f109ls7714324qge.27.gmail; Mon, 29 Dec 2014 11:35:41 -0800 (PST) X-Received: by 10.140.29.138 with SMTP id b10mr56449278qgb.34.1419881741281; Mon, 29 Dec 2014 11:35:41 -0800 (PST) Original-Received: from mail-qc0-x22e.google.com (mail-qc0-x22e.google.com. [2607:f8b0:400d:c01::22e]) by mx.google.com with ESMTPS id c6si15359095qan.115.2014.12.29.11.35.41 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 29 Dec 2014 11:35:41 -0800 (PST) Received-SPF: pass (google.com: domain of olafvdspek@gmail.com designates 2607:f8b0:400d:c01::22e as permitted sender) client-ip=2607:f8b0:400d:c01::22e; Original-Received: by mail-qc0-f174.google.com with SMTP id c9so9709170qcz.5 for ; Mon, 29 Dec 2014 11:35:41 -0800 (PST) X-Received: by 10.229.225.195 with SMTP id it3mr42397721qcb.24.1419881741012; Mon, 29 Dec 2014 11:35:41 -0800 (PST) Original-Received: by 10.229.151.70 with HTTP; Mon, 29 Dec 2014 11:35:40 -0800 (PST) In-Reply-To: <34298b73-1e10-4efa-8527-e1caf84c719c@isocpp.org> X-Original-Sender: olafvdspek@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of olafvdspek@gmail.com designates 2607:f8b0:400d:c01::22e as permitted sender) smtp.mail=olafvdspek@gmail.com; dkim=pass header.i=@gmail.com; dmarc=pass (p=NONE dis=NONE) header.from=gmail.com 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:15372 Archived-At: On Mon, Dec 29, 2014 at 8:34 PM, Leo Heinsaar wrote: > > > On Monday, December 29, 2014 11:26:52 PM UTC+4, Olaf van der Spek wrote: >> >> On Mon, Dec 29, 2014 at 8:17 PM, Leo Heinsaar wrote: >> >> I can't think what behavior would be introduced that would be >> >> surprising; can you please elaborate? >> > >> > >> > On a general note: once we convert something to bool, there is no >> > stopping >> > it from interacting with other fundamental types from short to double. >> > Just >> > seems that for iterators, that might introduce unnecessary type-safety >> > bugs. >> >> That's why we've got explicit operator bool. > > > Well, originally, at least, Matthew wrote: "Maybe we could instead create a > form of ::find() that returns an optional or checked_iterator or > similar, that can be implicitly cast to bool to test for validity." > > But even if it is made explicit, seems like it becomes too verbose to write > static_cast. Not necessary as if (v) and some other constructs count as explicit conversions already... -- Olaf -- --- 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/. .