220 15378 <3516872.4RhFvKrMWZ@tjmaciei-mobl4> article Path: news.gmane.org!not-for-mail From: Thiago Macieira 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 23:42:14 -0200 Lines: 43 Approved: news@gmane.org Message-ID: <3516872.4RhFvKrMWZ@tjmaciei-mobl4> References: <0959f2f8-acdd-4786-b6f3-0f05c62dcee6@isocpp.org> <3990670.unDteUsXEa@tjmaciei-mobl4> 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 1419903745 24780 80.91.229.3 (30 Dec 2014 01:42:25 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 30 Dec 2014 01:42:25 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBCB4TK757YBRB6UFRCSQKGQEWSRVPIQ@isocpp.org Tue Dec 30 02:42:20 2014 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-ee0-f72.google.com ([74.125.83.72]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Y5lpE-0001lz-D9 for gclcip-std-proposals@m.gmane.org; Tue, 30 Dec 2014 02:42:20 +0100 Original-Received: by mail-ee0-f72.google.com with SMTP id e53sf8531460eek.7 for ; Mon, 29 Dec 2014 17:42:19 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:subject:date:message-id:user-agent :in-reply-to:references:mime-version: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=rSEqwS22YAtl9R/Eupt6f4VPSYBl1+Jg8q84S28Dk8U=; b=KAOWReDZJbvaTxYoMMAJ4vCykmnGKvkOno8WxKzX9j02dGAgBB4rb7bIxBZ6K5k2pF 2XpMmv+Z63H9QVOWCUceO9BjTXDmy9gjXFB4F0NNbibHy3iujksSSJM+h2+ds/7WKKm7 XwNVBXy8XE593DgFWru82DoxoBopyLDlvFBAoAkDvyVOgai6+zhNjLaNN+/WJGvnDZOQ o/abq2RbN3v1qdeWuV6hkAtbMbD0KM2BWQMNpvBBLD38huyZJBAYIl3RTF1j3VtIWlWM 3bNLBw1LZ2zfzrXl70j7HZfZkFU18cFJNhjASThLFp2A07F2hUEsSb+z6BcwUs9xDULG 4gEw== X-Gm-Message-State: ALoCoQlC7/4Jy0IVKi6ZPo/RE8a8AK1REfb7UnFJS+G+qpjpjByr3P5DiWdhBiMWLeku6muuOKnt X-Received: by 10.180.77.167 with SMTP id t7mr6202092wiw.6.1419903739722; Mon, 29 Dec 2014 17:42:19 -0800 (PST) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.180.93.101 with SMTP id ct5ls1834793wib.22.canary; Mon, 29 Dec 2014 17:42:18 -0800 (PST) X-Received: by 10.194.188.13 with SMTP id fw13mr112956925wjc.83.1419903738570; Mon, 29 Dec 2014 17:42:18 -0800 (PST) Original-Received: from gondolin.macieira.info (gondolin.macieira.info. [78.47.120.188]) by mx.google.com with ESMTP id jx7si62365861wid.54.2014.12.29.17.42.18 for ; Mon, 29 Dec 2014 17:42:18 -0800 (PST) Received-SPF: pass (google.com: domain of thiago@macieira.org designates 78.47.120.188 as permitted sender) client-ip=78.47.120.188; Original-Received: from tjmaciei-mobl4.localnet (unknown [189.0.120.56]) by gondolin.macieira.info (Postfix) with ESMTPSA id B93A511BAF3 for ; Mon, 29 Dec 2014 17:42:17 -0800 (PST) User-Agent: KMail/4.14.3 (Linux/3.11.10-21-desktop; KDE/4.14.3; x86_64; ; ) In-Reply-To: X-Original-Sender: thiago@macieira.org X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of thiago@macieira.org designates 78.47.120.188 as permitted sender) smtp.mail=thiago@macieira.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:15378 Archived-At: On Monday 29 December 2014 19:17:49 Olaf van der Spek wrote: > Are you a QT dev? If so, could you file issues to improve these? Yes. > > Another case I've found is the checking if an element is present in a > > container before inserting it. That indicates we need a new method to > > "insert > > if not present" and the find method would not have helped. > > The find method can easily be used as a contains method. How would it > not have helped? Because the pattern is: if (!container.contains(x)) container.insert(x, value); Using find wouldn't help since it would still require two lookups (once for searching, once for inserting). > > QString is a container, so it's a valid match. It's not easy to do a full > > match due to -fvisibility-inlines-hidden. > > But it's not the traditional one-element find, would it work with a > generic contains? It has a contains(QChar), in spite of having other ones. -- Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org Software Architect - Intel Open Source Technology Center PGP/GPG: 0x6EF45358; fingerprint: E067 918B B660 DBD1 105C 966C 33F5 F005 6EF4 5358 -- --- 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/. .