220 14123 article Path: news.gmane.org!not-for-mail From: Olaf van der Spek Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Reconstruct function idea Date: Wed, 22 Oct 2014 08:32:41 -0700 (PDT) Lines: 78 Approved: news@gmane.org Message-ID: References: <8a74f08b-7453-4d1a-9f20-bc1d3866617c@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_6167_1547664504.1413991961729" X-Trace: ger.gmane.org 1413991971 3856 80.91.229.3 (22 Oct 2014 15:32:51 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 22 Oct 2014 15:32:51 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBC5NB45SSABBBGU4T6RAKGQEWMTG72I@isocpp.org Wed Oct 22 17:32:44 2014 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-oi0-f69.google.com ([209.85.218.69]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Xgxu0-0006pb-4B for gclcip-std-proposals@m.gmane.org; Wed, 22 Oct 2014 17:32:44 +0200 Original-Received: by mail-oi0-f69.google.com with SMTP id u20sf14775924oif.8 for ; Wed, 22 Oct 2014 08:32:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:message-id:in-reply-to:references:subject:mime-version :x-original-sender:reply-to:precedence:mailing-list:list-id :list-post:list-help:list-archive:list-subscribe:list-unsubscribe :content-type; bh=FcgWUpGbcjUw70SNiH3iC2YdD48PH5xIQWLlLZePwBQ=; b=pD/n70F9mYz6ivi9KsFZEij0QFYT7MulV0BXWi+fHo4t+Gq8zWd767QGiofkaIfeCE D0NIWYYB09d/rrCckhJO98bSdWJIuHViQcWA444VEs8f6piF1I3P5Q6fRD3MqOL9JuBI h3DyfLN5GWz0FPUn9ufNva3CgHmzqqO4E5D5reqsrjaF4MQKk1AKeBqkHbi0NPxaSwO+ UEf/QG+5PhcHzZj1wmByMZQvHQRlmsVUdOW5f75U7qjqRSDfSY9BuKtkFakyexGRc+4q FugSiFGXdyaWKkPjXYIpLtltX7mmZDhWYsR4Dg65Vq6+utynZ5/NWyQVQLOOpsFU5LFW jWDw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:message-id:in-reply-to:references :subject:mime-version:x-original-sender:reply-to:precedence :mailing-list:list-id:list-post:list-help:list-archive :list-subscribe:list-unsubscribe:content-type; bh=FcgWUpGbcjUw70SNiH3iC2YdD48PH5xIQWLlLZePwBQ=; b=EKJVOrLBpq6nh+9SnprE69mHv1NzZbIo4bg5QQRZWOB48yalZYbE27Z4UiTQlAR/Yl yX0EUNfVqDsrQj2qqhiKNVIZGkc7wTVOCnkebugJeSnN7QmCENQqzyWrZ1xgnhgHCj0Y /VhdNl6WD6hUDs3JQqejjU/++ZClGn6ibgkG1DG8YRqEg0+RNo6FsmTm6COIfXm0cT/2 JetJeglQbOJKN5/zOZ2CH7hTnclEoyRNnIpBYrqNIEqHB+pkUFUVyCrEjuw9+DyPWgeN Q/G5hYAGcPGuJirvnde1sFDUNWYtYOD+3fOq3Wx5EtKlxNzFDE3yKNnHH0xBWqQAL3CB uJkQ== X-Gm-Message-State: ALoCoQmKnlEVL15COJ9jZ7BK26dysoRB0IJbe6EFqKKBdh2CxRtWe0c9BHOFv5m7XYHs5fWp7X3P X-Received: by 10.182.4.7 with SMTP id g7mr28875887obg.36.1413991963228; Wed, 22 Oct 2014 08:32:43 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.140.20.44 with SMTP id 41ls827071qgi.26.gmail; Wed, 22 Oct 2014 08:32:42 -0700 (PDT) X-Received: by 10.140.30.36 with SMTP id c33mr255182qgc.7.1413991962691; Wed, 22 Oct 2014 08:32:42 -0700 (PDT) In-Reply-To: X-Original-Sender: olafvdspek@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:14123 Archived-At: ------=_Part_6167_1547664504.1413991961729 Content-Type: text/plain; charset=UTF-8 On Wednesday, October 15, 2014 11:48:11 PM UTC+2, Nevin ":-)" Liber wrote: > > > On 15 October 2014 16:17, Myriachan > > wrote: > >> While that is a nice feature, it's not the same as needing to do this to >> types that weren't created as std::optional. >> > > It is also *extremely* unsafe to do it with any class that can throw an > exception during construction or destruction. Why would we want to > encourage such a bad habit? I would vote strongly against such a > proposal. Even if you SFINAEed it so that it only worked with constructors > and destructors marked noexcept, I'd still vote against it, as 99% of users > should never use such a function. > > Dear Nevin, Why do you have bring up voting so often? -- --- 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/. ------=_Part_6167_1547664504.1413991961729 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable


On Wednesday, October 15, 2014 11:48:11 PM UTC+2, = Nevin ":-)" Liber wrote:

On 15 October 2014 16:17, Myriach= an <myri...@gmail= ..com> wrote:
While tha= t is a nice feature, it's not the same as needing to do this to types that = weren't created as std::o= ptional<T>.

It is also ext= remely unsafe to do it with any class that can throw an exception = during construction or destruction.  Why would we want to encourage su= ch a bad habit?  I would vote strongly against such a proposal.  = Even if you SFINAEed it so that it only worked with constructors and destru= ctors marked noexcept, I'd still vote against it, as 99% of users should ne= ver use such a function.

Dear Nevin,

Why do you have bring up voting so often?

<= /div>

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