Path: ...!2.eu.feeder.erje.net!feeder.erje.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Keith Thompson Newsgroups: comp.lang.c Subject: Re: constexpr keyword is unnecessary Date: Sat, 19 Oct 2024 21:08:10 -0700 Organization: None to speak of Lines: 35 Message-ID: <87plnvpgb9.fsf@nosuchdomain.example.com> References: <877ca5q84u.fsf@nosuchdomain.example.com> <87y12jpxvl.fsf@nosuchdomain.example.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Date: Sun, 20 Oct 2024 06:08:11 +0200 (CEST) Injection-Info: dont-email.me; posting-host="cc5061371ac78e01141ee4e1be7cb736"; logging-data="293103"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/gkYPWyYboegQ4V3z8MIdM" User-Agent: Gnus/5.13 (Gnus v5.13) Cancel-Lock: sha1:vgdC/4XOgg9VaWSbpJsRPfKXQH8= sha1:JB4wovMecnRSabLCtw6R/5ouw4A= Bytes: 2647 Thiago Adams writes: > Em 10/19/2024 6:48 PM, Keith Thompson escreveu: [...] >> My reasons for not wanting `const int c = 2;` to make c a constant >> expression have nothing to do with any theoretical difference in >> generated code. >> >> My reason is that "const" and "constant" are two almost entirely >> distinct concepts. Conflating them makes the language more confusing. >> Making the name of a "const" object a constant expression adds no new >> capabilities beyone what we already have with "constexpr". > > I see some differences but not enough to justify a new keyword and I > think it also generates confusion. So it is a matter of choosing what > that of confusion we want. But the new keyword already exists, and will be part of the language for years. Removing the constexpr keyword will not be possible, because doing so would break existing code. > For instance, in file scope, > > const int a = 1; > constexpr int b =1; > > In both cases, because it is file scope, a and b need to be > initialized with constant expressions. I don´t see anything more > special in b compared with a to make any distinction. As of C23, you're right. But what if a future C standard allows non-constant initializers for file-scope object (as C++ already does)? -- Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com void Void(void) { Void(); } /* The recursive call of the void */