220 33859 <829f1a52-f28a-4aca-92fd-bb4e98e865dc@isocpp.org> article Path: news.gmane.org!.POSTED!not-for-mail From: Niall Douglas Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: string_view for fstream::open() Date: Sat, 12 Aug 2017 08:23:44 -0700 (PDT) Lines: 101 Approved: news@gmane.org Message-ID: <829f1a52-f28a-4aca-92fd-bb4e98e865dc@isocpp.org> References: <3456831.gsseCm4DuK@tjmaciei-mobl1> <6240d6af-a518-4788-a56f-b7d0c8976dc4@isocpp.org> <01739e89-fc83-428b-94d5-e4e06927cc80@isocpp.org> <25b20004-c1b3-4844-b957-ef57e043b533@isocpp.org> <15b49197-b38b-47be-aefb-0786af7635f2@isocpp.org> <188dc31c-df5e-4fe1-ad85-847d3d732880@isocpp.org> <586cd0e2-2fd9-4af0-814c-7ca19ecac410@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_Part_3052_1391438201.1502551424426" X-Trace: blaine.gmane.org 1502551430 23970 195.159.176.226 (12 Aug 2017 15:23:50 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sat, 12 Aug 2017 15:23:50 +0000 (UTC) To: ISO C++ Standard - Future Proposals Original-X-From: std-proposals+bncBDGKFT5YZADRBAN3XTGAKGQETJC7T4A@isocpp.org Sat Aug 12 17:23:44 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-it0-f70.google.com ([209.85.214.70]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dgYGK-0005eq-Ob for gclcip-std-proposals@m.gmane.org; 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Sat, 12 Aug 2017 08:23:46 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.107.12.201 with SMTP id 70ls2833291iom.22.gmail; Sat, 12 Aug 2017 08:23:45 -0700 (PDT) X-Received: by 10.31.9.212 with SMTP id 203mr108591vkj.28.1502551425074; Sat, 12 Aug 2017 08:23:45 -0700 (PDT) In-Reply-To: <586cd0e2-2fd9-4af0-814c-7ca19ecac410@isocpp.org> X-Original-Sender: nialldouglas14@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:33859 Archived-At: ------=_Part_3052_1391438201.1502551424426 Content-Type: multipart/alternative; boundary="----=_Part_3053_1734689408.1502551424426" ------=_Part_3053_1734689408.1502551424426 Content-Type: text/plain; charset="UTF-8" On Friday, August 11, 2017 at 11:48:14 PM UTC+1, Nicol Bolas wrote: > > On Friday, August 11, 2017 at 6:29:23 PM UTC-4, Niall Douglas wrote: >> >> >>> Or we can just have a single `filesystem::path` type, which you can get >>> views of with existing types. I prefer that option. >>> >> >> As already covered in great detail by now, if fed a string_view then one >> is mandated to memcpy the lot so it can be zero terminated before sending >> it to the file path consuming syscall. >> > > A problem easily solved with the types we're talking about. We don't need > a replacement for `filesystem::path`. We *certainly* don't need some 32KB > type... > I hate to be slightly rude, but you really don't know what you're talking about on this. Try doing some benchmarking of the actual cost of a potentially unused 64Kb stack allocation in a routine which calls any path consuming syscall, and compare it to any other solution. Then feel free to retract your claim above. Furthermore, you once again misrepresent what I said. Nobody is replacing filesystem::path. afio::path_view *complements* filesystem::path with a usefully orthogonal API design. AFIO itself switches between both path_view and path as appropriate to use case. So will any other code. That's why the design is so correct, path_view does not replace path, it *augments* it. Niall -- 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/829f1a52-f28a-4aca-92fd-bb4e98e865dc%40isocpp.org. ------=_Part_3053_1734689408.1502551424426 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
On Friday, August 11, 2017 at 11:48:14 PM UTC+1, Nicol Bol= as wrote:
On F= riday, August 11, 2017 at 6:29:23 PM UTC-4, Niall Douglas wrote:

Or we can just have a single `filesyst= em::path` type, which you can get views of with existing types. I prefer th= at option.

As already covered i= n great detail by now, if fed a string_view then one is mandated to memcpy = the lot so it can be zero terminated before sending it to the file path con= suming syscall.

A problem easily solved wi= th the types we're talking about. We don't need a replacement for `= filesystem::path`. We certainly don't need some 32KB type...
=

I hate to be slightly rude, bu= t you really don't know what you're talking about on this.

Try doing some benchmarking of the actual cost of a potent= ially unused 64Kb stack allocation in a routine which calls any path consum= ing syscall, and compare it to any other solution. Then feel free to retrac= t your claim above.

Furthermore, you once again mi= srepresent what I said. Nobody is replacing filesystem::path. afio::path_vi= ew complements=C2=A0filesystem::path with a usefully orthogonal API = design. AFIO itself switches between both path_view and path as appropriate= to use case. So will any other code. That's why the design is so corre= ct, path_view does not replace path, it augments=C2=A0it.
=
Niall
=C2=A0

--
You received this message because you are subscribed to the Google Groups &= quot;ISO C++ Standard - Future Proposals" group.
To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposa= ls+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/829f1a52-f28a-4aca-92fd-bb4e98e865dc= %40isocpp.org.
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