220 32834 <88f0eeb9-c80f-4245-8231-bddacda98832@isocpp.org> article Path: news.gmane.org!.POSTED!not-for-mail From: Halfdan Ingvarsson Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: std::enum Date: Wed, 21 Jun 2017 05:38:53 -0700 (PDT) Lines: 80 Approved: news@gmane.org Message-ID: <88f0eeb9-c80f-4245-8231-bddacda98832@isocpp.org> References: <1cdd0fbf-c65d-4034-82d1-a84d4c4f6d1c@isocpp.org> <546143ae-5acd-4a0e-abde-4f712c51ca30@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_Part_3150_985148847.1498048733266" X-Trace: blaine.gmane.org 1498048734 17407 195.159.176.226 (21 Jun 2017 12:38:54 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 21 Jun 2017 12:38:54 +0000 (UTC) To: ISO C++ Standard - Future Proposals Original-X-From: std-proposals+bncBD5MZ4NLUIMRBXORVHFAKGQEJUVXNMI@isocpp.org Wed Jun 21 14:38:49 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-it0-f70.google.com ([209.85.214.70]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dNeuH-0004Ej-DW for gclcip-std-proposals@m.gmane.org; Wed, 21 Jun 2017 14:38:49 +0200 Original-Received: by mail-it0-f70.google.com with SMTP id u127sf2749164itg.11 for ; Wed, 21 Jun 2017 05:38:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isocpp-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:message-id:in-reply-to:references:subject:mime-version :x-original-sender:reply-to:precedence:mailing-list:list-id :list-post:list-help:list-archive:list-subscribe:list-unsubscribe; bh=0JNQ5naL9xLojDnGDpiuPnVvl9PqHiNkM4zCjgjfZDU=; b=JmTz2Uuodcw/qJ4vwECVJvuE5fMEVAJvwequ52y0QjEbVEsRREaYFfzqVb8PeUOyKt vtCRKodMfp5q9M5tq5Qr8CB3tBtmzJknU/H2B5J1bx2rDJ7QHSJWYlKSZVJrJQaXLjef eqIP2JOtDwDDc+CQNVgTc4Z+CqhzfAd5e2L42bxxTgEcplZyZlp4vKwNQDRyHDLczoAK vMm3Eso2NcyWvjVo6usVTjuARM0uFTYCbGqlz1peStDOPVd+oOm7JMKMcUhl5DB20CAM RAiBdrsDzqoccQ/0eoDjx+TpUT603NDgcIhVakF3yKSkr3dAvNX9dslDsyfv7GdS2MM5 d6og== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:message-id:in-reply-to:references:subject:mime-version :x-original-sender:reply-to:precedence:mailing-list:list-id :list-post:list-help:list-archive:list-subscribe:list-unsubscribe; bh=0JNQ5naL9xLojDnGDpiuPnVvl9PqHiNkM4zCjgjfZDU=; b=jVWgTXC37FVoxuaJpc7T0dlmYMyhGzl6ynyqTZ88JzA8IiapGOjQjL0CNc2KOfkNhU P/wCz84zw0AySJptbsoc940/Ud4JX/f+oypknf8Yh6LXtI7xCL15Iv3YPw80TUZp7sHI NlU7nrMjAJuldCm2DaB4TW0dE0BjWTXGuB1ial+F+WqOGeiYV+SMYnzXYo5xjlsVFAwy qGL6y1yP0Y74Iq+0Bwzz8niAYK/u6fiCs6bB9qyEiplYzF5synln+mhd/t84bYP9KRHX rjmZIim+PvU2CUJ6amtQsp/wZZEUM0OXxnJ9IZEQHoRBMO0kTStp0+1tN3LsLjV5J+kB iQCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:message-id:in-reply-to:references :subject:mime-version:x-original-sender:reply-to:precedence :mailing-list:list-id:x-spam-checked-in-group:list-post:list-help :list-archive:list-subscribe:list-unsubscribe; bh=0JNQ5naL9xLojDnGDpiuPnVvl9PqHiNkM4zCjgjfZDU=; b=QRAgpg0NQXEdvPGsE0yt5b45CN4J6JHoZSadTK52nfG9yghSJ/2TwcyCMFNbfITJ+/ 8oEwwyj5pChqqORtKz+HaOJLZY+3z6R0GwJw/U+4nTuA3HDdfP7Xf5zZNAAvb/vTMrsA VJOcD+8CLfYo3xqtfosGwrCU5IUg0L0jdTnWNSZ+fh/TXa7tVQCRoklhuzuVAD17o2+W GOVRb5wfqxyA8kSThpXTZ++gRvqHY1SGNI7nROnukdqBaomI6Pa9F6tDZuIkd62RiBsF rpT6kQcGiCTVMbRna/IthGodfju5pj1bM/P7W44zKP2vByPBagzT920NZSMNaEb9TkuD srXA== X-Gm-Message-State: AKS2vOx8LAdj38twBOoHAhAGFNrWvvcCHHelbzumH0LX5IgGMmIS34Bw XbI12+1iNagmRevb X-Received: by 10.107.27.198 with SMTP id b189mr17739665iob.38.1498048734503; Wed, 21 Jun 2017 05:38:54 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.157.29.194 with SMTP id w2ls3918770otw.28.gmail; Wed, 21 Jun 2017 05:38:53 -0700 (PDT) X-Received: by 10.157.12.161 with SMTP id b30mr1087415otb.3.1498048733752; Wed, 21 Jun 2017 05:38:53 -0700 (PDT) In-Reply-To: <546143ae-5acd-4a0e-abde-4f712c51ca30@isocpp.org> X-Original-Sender: halfdan@gmail.com 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:32834 Archived-At: ------=_Part_3150_985148847.1498048733266 Content-Type: multipart/alternative; boundary="----=_Part_3151_427242366.1498048733266" ------=_Part_3151_427242366.1498048733266 Content-Type: text/plain; charset="UTF-8" On Wednesday, June 21, 2017 at 12:12:44 AM UTC-4, wei zhang wrote: > > I won't think it can be done with only add lib. > For the samething I would suggest enum class will have a static const > variable array. > so that you could write > const auto & e =Color.array > That's why I mentioned that it would have to have some help from the compiler. For example, std::underlying_type, on clang and gcc, rely on an intrinsic called __underlying_type(), which takes a type argument. In this case there needs to be something like __enum_members(), which would be substituted by an braced init list that contains the enum members at compile time. -- 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/88f0eeb9-c80f-4245-8231-bddacda98832%40isocpp.org. ------=_Part_3151_427242366.1498048733266 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable


On Wednesday, June 21, 2017 at 12:12:44 AM UTC-4, = wei zhang wrote:
I won't think it can be done with only add lib.
For the samethin= g I would suggest enum class will have a static const variable array.
=
so that you could write
const auto & e =3DColor.array

That's why I ment= ioned that it would have to have some help from the compiler.
For example, std::underlying_type, on clang and gcc, rely on an= intrinsic called __underlying_type(), which takes a type argument. In this= case there needs to be something like __enum_members(), which would be sub= stituted by an braced init list that contains the enum members at compile t= ime.

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To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposa= ls+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/88f0eeb9-c80f-4245-8231-bddacda98832= %40isocpp.org.
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