220 28420 <3d03cd7d-2177-98fd-408d-f74b1f6a8552@gmail.com> article Path: news.gmane.org!.POSTED!not-for-mail From: Andrey Semashev Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Marking more std::string_view members noexcept Date: Tue, 27 Sep 2016 15:21:18 +0300 Lines: 31 Approved: news@gmane.org Message-ID: <3d03cd7d-2177-98fd-408d-f74b1f6a8552@gmail.com> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed X-Trace: blaine.gmane.org 1474978887 26238 195.159.176.226 (27 Sep 2016 12:21:27 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 27 Sep 2016 12:21:27 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 To: ISO C++ Standard - Future Proposals Original-X-From: std-proposals+bncBCXY5TXHWYJRBQOIVG7QKGQET2UYTQA@isocpp.org Tue Sep 27 14:21:22 2016 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-wm0-f69.google.com ([74.125.82.69]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1borNw-0005qk-Ud for gclcip-std-proposals@m.gmane.org; Tue, 27 Sep 2016 14:21:20 +0200 Original-Received: by mail-wm0-f69.google.com with SMTP id l132sf5698152wmf.0 for ; Tue, 27 Sep 2016 05:21:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isocpp-org.20150623.gappssmtp.com; s=20150623; h=to:from:subject:message-id:date:user-agent:mime-version :x-original-sender:x-original-authentication-results:reply-to :precedence:mailing-list:list-id:x-spam-checked-in-group:list-post :list-help:list-archive:list-subscribe:list-unsubscribe; bh=KbbBrsE6B4OWQsdGc50colhYjtQNjck1LRqWKdd+cyY=; b=gk4LOj2fcAEZetFzGy9HZKWSTCVgmMjz808jaQvRdbGl3PPPTkjC3HdLuYtLMq21Qq zLLQMQgk9Mj+3/3jEZYTTCkaEXSc7DL68FXb6jrcrc1UgZfo4cT3eX0pmyeSmQC/GyuD 1fqHb8NSGOpp11IDmTjlSBXY1ES1QHTQJbezv1PIhGMObhWsMcPqOWA/xps82HONrO5K kom4UrIUg+r5214bQQfgXvRdJoTvlybDXPt6ej5T3/ZwpMVzizyZsa8A9FbhQWZtLqnZ LfSXiXXsuPRVYrcWalfYfyy887P4Fa9zKYFK+Q+A4wz3ryKA5NxgovcuLDPYJyj1zRU1 r4hA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:to:from:subject:message-id:date:user-agent :mime-version:x-original-sender:x-original-authentication-results :reply-to:precedence:mailing-list:list-id:x-spam-checked-in-group :list-post:list-help:list-archive:list-subscribe:list-unsubscribe; bh=KbbBrsE6B4OWQsdGc50colhYjtQNjck1LRqWKdd+cyY=; b=IzPofeoUc5+vwsTlCbECNulVfR40EwjViuFrVl6IVgX1bIZ/cVEeygEbGlv06iBivE yeYYFbOiLu8abVwTsObC91brqmcWBWH7nE0ZddYHcIycLFlALc3AwBD3htQD0p661qtB Am+LZM9WTyt4DsxGpC4M7qnOgqxSUl9u0PqaFYATsXSbaFu0R19jXz9nVthcYX91UKmf WsUhNXbHXCearKEGfDbvcQmzGMrl1M9Bu7wXMTKs5nx0A8qmTaY2mQ24M+L08IkeZ0s7 UfM/DjEIZB4aNpqBhnYmNjG47p8OKAZOhvRyvyv6lgTGl0SfM59BoGQZVgtlVpDAus7f m9bg== X-Gm-Message-State: AA6/9Rm0oIQhzXcXtEzZKgU/A1p3MbE/3pWTX3de8ZkrX8EKzuB/xUb3OYO+d7FigZcojQ== X-Received: by 10.28.4.200 with SMTP id 191mr197188wme.21.1474978882589; Tue, 27 Sep 2016 05:21:22 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.46.5.196 with SMTP id 187ls1485918ljf.2.gmail; Tue, 27 Sep 2016 05:21:21 -0700 (PDT) X-Received: by 10.25.75.196 with SMTP id y187mr8333507lfa.151.1474978881020; Tue, 27 Sep 2016 05:21:21 -0700 (PDT) Original-Received: from mail-lf0-x22a.google.com (mail-lf0-x22a.google.com. [2a00:1450:4010:c07::22a]) by mx.google.com with ESMTPS id c69si954896lfe.10.2016.09.27.05.21.20 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 27 Sep 2016 05:21:21 -0700 (PDT) Received-SPF: pass (google.com: domain of andrey.semashev@gmail.com designates 2a00:1450:4010:c07::22a as permitted sender) client-ip=2a00:1450:4010:c07::22a; Original-Received: by mail-lf0-x22a.google.com with SMTP id b71so20606526lfg.0 for ; Tue, 27 Sep 2016 05:21:20 -0700 (PDT) X-Received: by 10.25.37.18 with SMTP id l18mr11266612lfl.88.1474978880311; Tue, 27 Sep 2016 05:21:20 -0700 (PDT) Original-Received: from [192.168.1.2] (broadband-90-154-68-136.nationalcablenetworks.ru. [90.154.68.136]) by smtp.googlemail.com with ESMTPSA id 202sm376366ljf.33.2016.09.27.05.21.19 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 27 Sep 2016 05:21:19 -0700 (PDT) X-Original-Sender: andrey.semashev@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com; spf=pass (google.com: domain of andrey.semashev@gmail.com designates 2a00:1450:4010:c07::22a as permitted sender) smtp.mailfrom=andrey.semashev@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:28420 Archived-At: Hi, I'm looking at string_view interface definition in N4606 and wondering why so many members are not marked noexcept? For example, these constructors: constexpr basic_string_view(const charT* str); constexpr basic_string_view(const charT* str, size_type len); Assuming that the input string is not a constant expression, the first constructor would call an equivalent of strlen(str), which in 99% is a no-throw operation. Why not mark it "noexcept(noexcept(traits::length(str))"? The second constructor does not even need that and could be simply noexcept. I'm most interested in constructors, but other members like operator[], front(), back(), substr(), compare() also don't seem to need to ever throw, yet they are not marked noexcept. Is there a reason for these omissions? Also, why there is no obvious constructor from basic_string? Thanks. -- 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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