220 35705 article Path: news.gmane.org!.POSTED!not-for-mail From: Matthew Woehlke Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: pragma once Date: Thu, 30 Nov 2017 12:04:14 -0500 Lines: 26 Approved: news@gmane.org Message-ID: References: <3d275c24-dc31-4fa7-a6db-e235ab2e00f1@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Trace: blaine.gmane.org 1512176054 28419 195.159.176.226 (2 Dec 2017 00:54:14 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sat, 2 Dec 2017 00:54:14 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBC37LBFWUIFBBL7TQ7IQKGQEM2CCZDI@isocpp.org Sat Dec 02 01:54:08 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qk0-f197.google.com ([209.85.220.197]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eKw49-0006jB-J8 for gclcip-std-proposals@m.gmane.org; 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Thu, 30 Nov 2017 09:04:25 -0800 (PST) Received-SPF: neutral (google.com: 195.159.176.226 is neither permitted nor denied by best guess record for domain of gclcip-std-proposals@m.gmane.org) client-ip=195.159.176.226; Original-Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1eKSG0-0006pQ-Te for std-proposals@isocpp.org; Thu, 30 Nov 2017 18:04:16 +0100 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 19 Original-X-Complaints-To: usenet@blaine.gmane.org In-Reply-To: Content-Language: en-US X-Original-Sender: mwoehlke.floss@gmail.com X-Original-Authentication-Results: mx.google.com; spf=neutral (google.com: 195.159.176.226 is neither permitted nor denied by best guess record for domain of gclcip-std-proposals@m.gmane.org) smtp.mailfrom=gclcip-std-proposals@m.gmane.org; dmarc=fail (p=NONE sp=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:35705 Archived-At: On 2017-11-30 10:56, Jake Arkinstall wrote: > How it works on other systems is a tough one, as is usually the case, but > in general if you have the ability to include a file and parse it, I can't > see why you won't also have the ability to hash it (perhaps with two > different salts, to give two hashes, to significantly reduce accidental > collisions between two different but well-formed files) and compare with > already-included files. So... you would make it *content*-based, rather than *name*-based? While I agree that is probably more useful, I believe it is a departure from current practice. (It's also potentially slow and problematic, since I believe current compilers can work on streams as well as files.) I tried something like that with http://wg21.link/p0538. The committee is basically uninterested in doing anything in this area. (Modules, as mentioned, is a major contributor to this disinterest.) -- Matthew -- 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/ovpdm7%24eqe%241%40blaine.gmane.org. .