220 41220 article Path: news.gmane.org!.POSTED!not-for-mail From: Ville Voutilainen Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Modules and preambule, just why? 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[209.85.220.41]) by mx.google.com with SMTPS id y9sor11218252oto.119.2018.12.05.11.02.12 for (Google Transport Security); Wed, 05 Dec 2018 11:02:12 -0800 (PST) Received-SPF: pass (google.com: domain of ville.voutilainen@gmail.com designates 209.85.220.41 as permitted sender) client-ip=209.85.220.41; X-Received: by 2002:a9d:501:: with SMTP id 1mr17071874otw.133.1544036531647; Wed, 05 Dec 2018 11:02:11 -0800 (PST) In-Reply-To: X-Original-Sender: ville.voutilainen@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=luChZlRJ; spf=pass (google.com: domain of ville.voutilainen@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=ville.voutilainen@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:41220 Archived-At: On Wed, 5 Dec 2018 at 20:47, wrote: > > After reading your answer and thinking about it in the last days, I thing I understand things a bit better now. > First I understand that module are far less related to the linking problem than I first tough. > Also, I think I better understand how they will actually work in real world application. > > Still, one question remains for me: > If for example you wanna ship a library. > As of today, you generally with the library the headers so that people using the library will be able to compile their code and make use of the library you made. > But how does it work if you wanna use modules? do you ship a module file together with the lib? And if so, how do you intend to generate this module file? Yes, you ship the module interface with your lib. You compile the module for the target implementation you want to support. > Also note that even if I better understand the proposal now, my doubts about it and the need of declaring the module explicitly remains. > In fact, I would have prefer an approach where the exported symbols are deduced from the code instead of having to declare it explicitly. Deduced how? The problem we have today with headers is that everything in a header needs to be parsed, whether part of the actual interface of the library or not. Modules give us control over what things are part of the interface and what things are not. -- 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/CAFk2RUaoP3h62RX10FfFv3ttyt1he96KJ_R_m%3DM7UA8%3Dbf0O3A%40mail.gmail.com. .