220 32537 article Path: news.gmane.org!.POSTED!not-for-mail From: Zhihao Yuan Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: constexpr ternary (was: Re: relaxing rules for ternary operator. Allow incompatible types.) 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[184.173.153.196]) by mx.google.com with UTF8SMTPS id k9si13484616qtc.216.2017.05.20.14.01.32 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 20 May 2017 14:01:32 -0700 (PDT) Received-SPF: pass (google.com: domain of bounce+3f9131.69110-std-proposals=isocpp.org@miator.net designates 184.173.153.196 as permitted sender) client-ip=184.173.153.196; Original-Sender: zy@miator.net X-Mailgun-Sending-Ip: 184.173.153.196 X-Mailgun-Sid: WyI3MTBkYiIsICJzdGQtcHJvcG9zYWxzQGlzb2NwcC5vcmciLCAiNjkxMTAiXQ== Original-Received: from mail-pg0-f53.google.com (mail-pg0-f53.google.com [74.125.83.53]) by mxa.mailgun.org with ESMTP id 5920aeac.7fc603ed3f30-smtp-out-n02; Sat, 20 May 2017 21:01:32 -0000 (UTC) Original-Received: by mail-pg0-f53.google.com with SMTP id u187so52019226pgb.0 for ; Sat, 20 May 2017 14:01:32 -0700 (PDT) X-Received: by 10.98.73.214 with SMTP id r83mr17408825pfi.12.1495314091946; Sat, 20 May 2017 14:01:31 -0700 (PDT) Original-Received: by 10.100.151.71 with HTTP; Sat, 20 May 2017 14:01:31 -0700 (PDT) In-Reply-To: <9dbebffff1732ae5966a93b69a836757@kdab.com> X-Gmail-Original-Message-ID: X-Original-Sender: zy@miator.net X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@miator.net; spf=pass (google.com: domain of bounce+3f9131.69110-std-proposals=isocpp.org@miator.net designates 184.173.153.196 as permitted sender) smtp.mailfrom=bounce+3f9131.69110-std-proposals=isocpp.org@miator.net 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:32537 Archived-At: --94eb2c0b916c473c5a054ffaf1bc Content-Type: text/plain; charset="UTF-8" On Sat, May 20, 2017 at 3:11 PM, Marc Mutz wrote: > >> auto x = (std::is_integral_v) ? A{} : B{}; >> >> This would be like if constexpr with implicit constexpr determinded by >> the compiler. >> > > I had the same idea the other day :) > > constexpr-if is explicit, why should the the ternary be different? > > auto x = std::is_integral_v constexpr ? A{} : B{}; > Seems not so hard? auto x = std::conditional_t, A, B>{}; -- Zhihao Yuan, ID lichray The best way to predict the future is to invent it. _______________________________________________ -- 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/CAGsORuBi-W4ZjOiBbmPCErmkEVsa1zehi6fRfXr1EJ%2B%3Dp6meyg%40mail.gmail.com. --94eb2c0b916c473c5a054ffaf1bc Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable

= On Sat, May 20, 2017 at 3:11 PM, Marc Mutz <marc.mutz@kdab.com> wrote:

auto x =3D (std::is_integral_v<T>) ? A{} : B{};

This would be like if constexpr with implicit constexpr determinded by
the compiler.

I had the same idea the other day :)

constexpr-if is explicit, why should the the ternary be different?

=C2=A0 auto x =3D std::is_integral_v<T> constexpr ? A{} : B{};

Seems not so hard?<= br>

= =C2=A0 auto x =3D std::conditional_t<std::is_integral_v<T>, A, B&g= t;{};

--
Zhih= ao Yuan, ID lichray
The best way to predict the future is to invent it.<= br>_______________________________________________

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