220 38751 article Path: news.gmane.org!.POSTED!not-for-mail From: Richard Hodges Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Safe Navigation Operator Date: Wed, 20 Jun 2018 16:45:10 +0200 Lines: 115 Approved: news@gmane.org Message-ID: References: <9f6e5511-efcd-4e4f-8776-0b869ed54a69@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="00000000000022fec1056f13d9f3" X-Trace: blaine.gmane.org 1529505796 25952 195.159.176.226 (20 Jun 2018 14:43:16 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 20 Jun 2018 14:43:16 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBD4PBM7UWAHRBAWRVHMQKGQEQC5ISIQ@isocpp.org Wed Jun 20 16:43:12 2018 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-io0-f199.google.com ([209.85.223.199]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fVeKG-0006dP-0g for gclcip-std-proposals@m.gmane.org; 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[209.85.220.41]) by mx.google.com with SMTPS id a2-v6sor1239623ita.71.2018.06.20.07.45.22 for (Google Transport Security); Wed, 20 Jun 2018 07:45:22 -0700 (PDT) Received-SPF: pass (google.com: domain of hodges.r@gmail.com designates 209.85.220.41 as permitted sender) client-ip=209.85.220.41; X-Received: by 2002:a24:96:: with SMTP id 144-v6mr1869992ita.76.1529505921561; Wed, 20 Jun 2018 07:45:21 -0700 (PDT) In-Reply-To: <9f6e5511-efcd-4e4f-8776-0b869ed54a69@isocpp.org> X-Original-Sender: hodges.r@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=ieDhtxj4; spf=pass (google.com: domain of hodges.r@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=hodges.r@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE 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:38751 Archived-At: --00000000000022fec1056f13d9f3 Content-Type: text/plain; charset="UTF-8" On Wed, 20 Jun 2018 at 16:36, Nicol Bolas wrote: > On Wednesday, June 20, 2018 at 6:01:57 AM UTC-4, saii...@gmail.com wrote: >> >> Hi, >> >> a Safe Navigation Operator like in C#, Ruby or Kotlin would make the code >> so much simpler and easier to read. >> > > This is only true because those languages do not have non-nullable > references. Or if they have them, they aren't the common case. > > I haven't written a lot of code that does so many chained accesses of > nullable references like verifying them becomes a syntactic burden of a > kind worthy of added syntax. We have the option to have functions return a > non-nullable reference, so in many cases, we don't return pointers. > > Having this many NULL checks suggests that maybe the system in question is > just poorly designed. > ^^ this ^^ > > Also, what happens if the function needs to return something? What you're > talking about can only be used in functions with no return values. That > seems decidedly limiting. > > -- > 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/9f6e5511-efcd-4e4f-8776-0b869ed54a69%40isocpp.org > > . > -- 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/CALvx3hZU8ZTfbumn7%2B5-mmphSWMOasohaXp%3DpdJRkHbOMsnoSQ%40mail.gmail.com. --00000000000022fec1056f13d9f3 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable


On Wed= , 20 Jun 2018 at 16:36, Nicol Bolas <jmckesson@gmail.com> wrote:
On Wednesday, June 20, 2018 at 6:01:57 AM UTC-4, saii...@gmail.com wro= te:
Hi,

a=C2=A0Safe Navigation Operator like in C#, Ruby or Kotlin would ma= ke the code so much simpler and easier to read.

This is only true because those languages do not have non-= nullable references. Or if they have them, they aren't the common case.=

I haven't written a lot of code that does so = many chained accesses of nullable references like verifying them becomes a = syntactic burden of a kind worthy of added syntax. We have the option to ha= ve functions return a non-nullable reference, so in many cases, we don'= t return pointers.

Having this many NULL checks su= ggests that maybe the system in question is just poorly designed.

^^ this ^^
=C2=A0

Also, what hap= pens if the function needs to return something? What you're talking abo= ut can only be used in functions with no return values. That seems decidedl= y limiting.

--
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