220 24971 article Path: news.gmane.org!not-for-mail From: Andrew Tomazos Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Any purposes for $, @, or ` ? 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[2607:f8b0:400c:c05::22a]) by mx.google.com with ESMTPS id 17si4582193vkp.147.2016.03.05.04.40.48 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 05 Mar 2016 04:40:48 -0800 (PST) Received-SPF: pass (google.com: domain of andrewtomazos@gmail.com designates 2607:f8b0:400c:c05::22a as permitted sender) client-ip=2607:f8b0:400c:c05::22a; Original-Received: by mail-vk0-x22a.google.com with SMTP id e6so78688954vkh.2 for ; Sat, 05 Mar 2016 04:40:48 -0800 (PST) X-Received: by 10.31.149.135 with SMTP id x129mr11111933vkd.62.1457181648316; Sat, 05 Mar 2016 04:40:48 -0800 (PST) Original-Received: by 10.103.39.195 with HTTP; Sat, 5 Mar 2016 04:40:48 -0800 (PST) In-Reply-To: <7B9B7D90-2756-4474-B5B3-8A62A6B3EB61@me.com> X-Original-Sender: andrewtomazos@gmail.com X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of andrewtomazos@gmail.com designates 2607:f8b0:400c:c05::22a as permitted sender) smtp.mailfrom=andrewtomazos@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-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:24971 Archived-At: --001a1141c87e857057052d4c8ae2 Content-Type: text/plain; charset=UTF-8 On Sat, Mar 5, 2016 at 1:33 PM, Alisdair Meredith wrote: > One of the reasons I had heard in the past is that as these are /not/ part > of the basic character set, implementations are free to use them in their > name mangling schemes. If we were to make them available for use in > identifiers, we risk breaking the ABI of some platforms. You will note > that > even using extended identifiers, these characters live in a region of > Unicode that is specifically excluded from use as a C++ identifier. > > It may be possible to make them available for use in future extensions > to the C++ syntax and grammar, but I suspect they are forever lost to > user-space for class, variable, and function names. > I concur. I think adding them to the basic character set is fine, but they could not be used in identifiers. They would serve as operator-or-punctuation tokens that are effectively "stripped" after parsing and the AST is formed. I've been considering writing a proposal to add these three characters to the basic source character set as a standalone action. After such a change, it would have no immediate effect, but if passed would remove FUD from using these characters in future proposed core language proposals, and create some much needed syntactic space in the language. > > AlisdairM > > > On Feb 27, 2016, at 8:47 AM, NDos Dannyu wrote: > > These three characters are not part of the basic source character set, > even though they are graphic ASCII characters. > Any purposes for them? > > -- > 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/94de1ee2-0821-418e-a7b1-87b61ea438eb%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/7B9B7D90-2756-4474-B5B3-8A62A6B3EB61%40me.com > > . > -- 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/CAB%2B4KHKw8K%2B6oFsbUnM4Wb%2BtUur6iE6Mus3xVyd2bWoyjOCP1w%40mail.gmail.com. --001a1141c87e857057052d4c8ae2 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
On S= at, Mar 5, 2016 at 1:33 PM, Alisdair Meredith <alisdairm@me.com> wrote:
One of the reasons I had heard in the past is that as these are /not/= part
of the basic character set, implementations are free to use them = in their
name mangling schemes.=C2=A0 If we were to make them ava= ilable for use in
identifiers, we risk breaking the ABI of some p= latforms.=C2=A0 You will note that
even using extended identifier= s, these characters live in a region of
Unicode that is specifica= lly excluded from use as a C++ identifier.

It may = be possible to make them available for use in future extensions
t= o the C++ syntax and grammar, but I suspect they are forever lost to
<= div>user-space for class, variable, and function names.

I concur.=C2=A0 I think adding them to the basic c= haracter set is fine, but they could not be used in identifiers.=C2=A0 They= would serve as operator-or-punctuation tokens that are effectively "s= tripped" after parsing and the AST is formed.

I've been considering writing a proposal to add these three characters= to the basic source character set as a standalone action.=C2=A0 After such= a change, it would have no immediate effect, but if passed would remove FU= D from using these characters in future proposed core language proposals, a= nd create some much needed syntactic space in the language.

<= /div>
=C2=A0

AlisdairM


On Feb 27, 2016, a= t 8:47 AM, NDos Dannyu <ndospark320@naver.com> wrote:

These three characters are not part of the basic source character= set, even though they are graphic ASCII characters.
Any purposes= for them?

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