220 26979 <87poqgyux3.fsf@gmail.com> article Path: news.gmane.org!not-for-mail From: Moritz Klammler Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Proposal - non allocating std::function Date: Thu, 14 Jul 2016 19:46:32 +0200 Lines: 32 Approved: news@gmane.org Message-ID: <87poqgyux3.fsf@gmail.com> 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 1468519881 13427 80.91.229.3 (14 Jul 2016 18:11:21 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 14 Jul 2016 18:11:21 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDHI7IWJYALRBN5LT66AKGQE3SE5ZPQ@isocpp.org Thu Jul 14 20:11:14 2016 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-lf0-f69.google.com ([209.85.215.69]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1bNl6M-0006Kv-CU for gclcip-std-proposals@m.gmane.org; Thu, 14 Jul 2016 20:11:10 +0200 Original-Received: by mail-lf0-f69.google.com with SMTP id l89sf58079689lfi.3 for ; Thu, 14 Jul 2016 11:11:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isocpp-org.20150623.gappssmtp.com; s=20150623; h=from:to:subject:date:in-reply-to:message-id: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=kQBI3piDuKArBMzUuh3wfeghY1XYa4z38E6u94tLCPo=; b=StLBfr1GU9lS02eUoGkZgufwgHJ6S8i4TD+ea1NVtNUF9dArMJYeuTASKZ90Y4SebK wnOl9z771LciQ0hCj3Tz+UaT30s82eq10eMEcfTfjL1t/eXUV5mxZXLzbEXHahAEYGiR Fng5OLcqWLRSZlwZzKMQXwj9dIQRv5Va40jBg96icIETDw5qkepN51h7YBvKzhr9sVVI nkkCaz5gEHOay6jInHl5OIQBDHGVPIa5q45f5NCynCD+szTS4s43U96KrY6cJ33aDQq5 etHsNfa5lULhgoJQ0thKekufvyJ8lZXrhSWgZtqcGlnl94pAQuhxQPRPl4dWqzcYA9pw zVVg== 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:in-reply-to:message-id :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=kQBI3piDuKArBMzUuh3wfeghY1XYa4z38E6u94tLCPo=; b=X5t0hi8B3KfnhDxdxzk3J/LqePHvFlNSkTB1SDSRah18bBe+NSD95Ys25pYCyEfxHj yJbnSEPzbk7mAAX8wQ83wlk9FJfhNrhgnd8aFjta4SnuqFtUaG35z5gRivplm2mNJ2lF PZd+BOwX1wLKkVd7JSRcrQr7jb6Ti7tv6fr/YkN2xIsS0HRwNShZvMTHOlQUrly0iGMv ZsG3TVw0Y8juhQGPZygTnHe860mHT37/1Vou7fUt5t/Uhma8+G50tYK3MLRkccyZrNF3 7vySS262hjY9ruDOmAdtW3tfK1OmZlbQ0w8E7/fmhLi8voxoDuvsh8/K37eMkpPSd9kY snHg== X-Gm-Message-State: ALyK8tJqIQCozpBBaOeMMQUOdL74UUNnkTQLjWk/y9/iiD4LN/BXSEaFpQaB8mY0TVH+Zw== X-Received: by 10.46.9.150 with SMTP id 144mr2653348ljj.0.1468519864833; Thu, 14 Jul 2016 11:11:04 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.28.169.144 with SMTP id s138ls4697wme.8.canary; Thu, 14 Jul 2016 11:11:03 -0700 (PDT) X-Received: by 10.28.107.144 with SMTP id a16mr18797860wmi.75.1468519863357; Thu, 14 Jul 2016 11:11:03 -0700 (PDT) Original-Received: from mail-wm0-x233.google.com (mail-wm0-x233.google.com. [2a00:1450:400c:c09::233]) by mx.google.com with ESMTPS id y135si33830086wmd.74.2016.07.14.11.11.03 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 14 Jul 2016 11:11:03 -0700 (PDT) Received-SPF: pass (google.com: domain of moritz.klammler@gmail.com designates 2a00:1450:400c:c09::233 as permitted sender) client-ip=2a00:1450:400c:c09::233; Original-Received: by mail-wm0-x233.google.com with SMTP id i5so123362071wmg.0 for ; Thu, 14 Jul 2016 11:11:03 -0700 (PDT) X-Received: by 10.28.174.76 with SMTP id x73mr17501717wme.60.1468519862446; Thu, 14 Jul 2016 11:11:02 -0700 (PDT) Original-Received: from moritz-laptop (openvpn-cl-200-65.scc.kit.edu. [141.3.200.65]) by smtp.gmail.com with ESMTPSA id z5sm3526983wme.5.2016.07.14.11.11.00 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 14 Jul 2016 11:11:00 -0700 (PDT) In-Reply-To: T. C.'s message of "Wed\, 13 Jul 2016 22\:58\:32 -0700 \(PDT\) \(11 hours\, 40 minutes\, 48 seconds ago\)" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) X-Original-Sender: moritz.klammler@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com; spf=pass (google.com: domain of moritz.klammler@gmail.com designates 2a00:1450:400c:c09::233 as permitted sender) smtp.mailfrom=moritz.klammler@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-Spam-Checked-In-Group: std-proposals@isocpp.org 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:26979 Archived-At: > I'm not clear as to what you mean here. Consider this: > > std::function a_func() > { > return []{}; > } > > What would the "stack-based array" equivalent look like? Would it look > as reasonable as this? Would it be able to use that nifty guaranteed > elision stuff we'll be getting? I think you'd have to pass the allocator as an argument to `a_func`. It would be more involved than your snippet but probably still "reasonable". Anyway, this... > The allocator support in std::function has been zapped as of three > weeks ago. makes my entire point obsolete, of course. The only remaining feedback I can provide then is to suggest you add a quick note to the motivation of the proposal that explains this. I was somehow irritated that the word "allocator" didn't appear a single time in a paper about memory allocation. If allocator support was removed for good reasons and the proposed approach is considered a superior replacement, mentioning this explicitly might help the uninvolved reader. -- 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. To view this discussion on the web visit https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/87poqgyux3.fsf%40gmail.com. .