220 12071 article Path: news.gmane.org!not-for-mail From: Ville Voutilainen Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Variadic catch Date: Fri, 25 Jul 2014 19:04:57 +0300 Lines: 30 Approved: news@gmane.org Message-ID: References: <53D270BF.5010906@gmx.de> <3f9efef6-04ec-47d7-807e-0d695bb2eba7@isocpp.org> <9E8291EE-CD67-4772-A364-0929FD18E295@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 1406304308 28648 80.91.229.3 (25 Jul 2014 16:05:08 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 25 Jul 2014 16:05:08 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBC5JHI7A7ALRBKUAZKPAKGQESW5MXJQ@isocpp.org Fri Jul 25 18:05:01 2014 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-pa0-f70.google.com ([209.85.220.70]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1XAhzQ-00039l-M9 for gclcip-std-proposals@m.gmane.org; Fri, 25 Jul 2014 18:05:00 +0200 Original-Received: by mail-pa0-f70.google.com with SMTP id lf10sf30392813pab.5 for ; Fri, 25 Jul 2014 09:04:59 -0700 (PDT) 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:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:list-post:list-help:list-archive:list-subscribe :list-unsubscribe:content-type; bh=9CY1cuGa1J31MBKbIeJ72tRWmWGUIlxkrfNiNAbD8LM=; b=FJXsuGOlc63HAbQcnSe/h1uVRaoJh+yenjBFce3qmHzCqdS95DirUdpj9/04uvhdjO X5heyMelA97YNoBc60xV6wFyUUlsTiG1VNiaOxpXjDVPLWnTQX1wC55pFqvh98aeInPF x8r3X1sTpaI15QEEtohB8Reczbn/HYf26MOkznmRs9RgLlka8uPDnXV8JGaXXldR7Vfx D3QDixbJgRTfz3AQtjd1UXyFnlSfDo3satb8xQGUxC5j+k20oA08OR8RgnZp35t4RoBY sRTfvDwEiKoaCseX6/fGisAKc6iwsvo5PxFesdQL9EmY1kZltRl7mq5zvTjJ7/Zp7tER Lssw== X-Gm-Message-State: ALoCoQlbb5mjGvH9MocJ0+Aw6kVPRceQYNLwJ1CCTYyWN+I2ct60s1v106WJWCHmPEngBbOLPWTJ X-Received: by 10.70.11.197 with SMTP id s5mr8328419pdb.0.1406304299213; Fri, 25 Jul 2014 09:04:59 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.140.50.77 with SMTP id r71ls1326801qga.71.gmail; Fri, 25 Jul 2014 09:04:58 -0700 (PDT) X-Received: by 10.140.98.118 with SMTP id n109mr27192001qge.13.1406304297994; Fri, 25 Jul 2014 09:04:57 -0700 (PDT) Original-Received: from mail-qa0-x22f.google.com (mail-qa0-x22f.google.com [2607:f8b0:400d:c00::22f]) by mx.google.com with ESMTPS id n9si17001554qas.94.2014.07.25.09.04.57 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 25 Jul 2014 09:04:57 -0700 (PDT) Received-SPF: pass (google.com: domain of ville.voutilainen@gmail.com designates 2607:f8b0:400d:c00::22f as permitted sender) client-ip=2607:f8b0:400d:c00::22f; Original-Received: by mail-qa0-f47.google.com with SMTP id i13so4691579qae.20 for ; Fri, 25 Jul 2014 09:04:57 -0700 (PDT) X-Received: by 10.140.36.118 with SMTP id o109mr26409837qgo.25.1406304297883; Fri, 25 Jul 2014 09:04:57 -0700 (PDT) Original-Received: by 10.224.31.137 with HTTP; Fri, 25 Jul 2014 09:04:57 -0700 (PDT) In-Reply-To: X-Original-Sender: ville.voutilainen@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of ville.voutilainen@gmail.com designates 2607:f8b0:400d:c00::22f as permitted sender) smtp.mail=ville.voutilainen@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:12071 Archived-At: On 25 July 2014 18:44, David Krauss wrote: > > On 2014-07-25, at 11:36 PM, Jeaye Wilkerson wrote: > >> Yes, the body of the catch block would need to be generic for each type, but, as with any generic API within the generic paradigm, that doesn't mean they should share a common base; they share a common public interface. > > That's just a bad design. The language shouldn't support it. Just because it's possible doesn't mean it's OK. What's bad design? A library providing multiple exception types that do not form a hierarchy? I disagree. There's nothing bad about it. Now, whether we need to provide a way to generate the code to catch all those different exception types and run the same code on all of them is a different matter. Work-arounds certainly seem to incur unfortunate costs - using a variable function template that re-throws and catches a specific type will lead to one re-throw per every type in the pack, as opposed to a single throw that this extension proposal would have. -- --- 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. 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