220 18655 <5582666F.8040501@gmx.net> article Path: news.gmane.org!not-for-mail From: Jens Maurer Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: Parsing Numbers Date: Thu, 18 Jun 2015 08:34:23 +0200 Lines: 69 Approved: news@gmane.org Message-ID: <5582666F.8040501@gmx.net> References: <4ddfb70a-a8ce-4fc3-82ee-3a5bb4239ff2@isocpp.org> <9761565.z80J1WOjpt@tjmaciei-mobl4> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Trace: ger.gmane.org 1434609284 12858 80.91.229.3 (18 Jun 2015 06:34:44 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 18 Jun 2015 06:34:44 +0000 (UTC) To: std-proposals@isocpp.org Original-X-From: std-proposals+bncBDPMTYGK64JRB4OMRGWAKGQEQACCVLQ@isocpp.org Thu Jun 18 08:34:36 2015 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-wi0-f197.google.com ([209.85.212.197]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Z5TPD-0005vh-NA for gclcip-std-proposals@m.gmane.org; Thu, 18 Jun 2015 08:34:31 +0200 Original-Received: by wimx15 with SMTP id x15sf1001724wim.1 for ; Wed, 17 Jun 2015 23:34:26 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:message-id:date:from:user-agent:mime-version:to :subject:references:in-reply-to:content-type:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:x-spam-checked-in-group:list-post:list-help:list-archive :list-subscribe:list-unsubscribe; bh=SdAjHlOEhEx9etft8VLIVGFObkHzYeZnUMk8KmymRYQ=; b=UMWxKVDdPJQf2/riMqYnmgGRdRFX2bjmQbYf1qUHOpAeTspHr7kugiRT1KStjNSekk 3/G+LR56bVzS3sb2DZKHTG95KIqazVyeHxQzjtiSwziou5eIJsHLKdi95VkqfkS2IvD9 6CoUUvVugo710RyY+jSa5Zg2YUtM6asH/+ZgMvRpT/OlmGRXzolU/GSZrjCrdjgN0Sv7 mXHogXWQFZqPNH3kx04vm+KR5rt1KNNmRxZaxg8/iEsI6j3Fg+qplPRSAhXMrQlXAjU6 XiJ54e3FQpHFm8Gv1PcBL9jHQUt0gfBJIOQHUzKYxaPiGoxXS0Nof0CNBnJF5XIu8jDi adng= X-Gm-Message-State: ALoCoQl6rMLezQNUBb295M1SvTkMoE6ek64O8LUN31MxOJFaEDzprD37fD0WvGvsA86pToULEgAA X-Received: by 10.112.171.41 with SMTP id ar9mr8907290lbc.24.1434609265957; Wed, 17 Jun 2015 23:34:25 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.180.102.41 with SMTP id fl9ls901927wib.24.canary; Wed, 17 Jun 2015 23:34:24 -0700 (PDT) X-Received: by 10.180.218.195 with SMTP id pi3mr25090556wic.71.1434609264579; Wed, 17 Jun 2015 23:34:24 -0700 (PDT) Original-Received: from mout.gmx.net (mout.gmx.net. [212.227.17.20]) by mx.google.com with ESMTPS id g14si12338006wjz.39.2015.06.17.23.34.24 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 17 Jun 2015 23:34:24 -0700 (PDT) Received-SPF: pass (google.com: domain of Jens.Maurer@gmx.net designates 212.227.17.20 as permitted sender) client-ip=212.227.17.20; Original-Received: from [10.0.47.10] ([85.181.215.12]) by mail.gmx.com (mrgmx102) with ESMTPSA (Nemesis) id 0ME47n-1ZLgPn05oF-00HMa4 for ; Thu, 18 Jun 2015 08:34:24 +0200 User-Agent: Mozilla/5.0 (X11; Linux i686; rv:6.0.1) Gecko/20110830 Thunderbird/6.0.1 In-Reply-To: <9761565.z80J1WOjpt@tjmaciei-mobl4> X-Provags-ID: V03:K0:Ba5KHXzNEi8V0qm+JiU8r0nj3pAwjEB4cEr+prJnS0UcQqcCHzh R6ItjHNkJlDym04mH+QPyTKL4TGXAVWBNOqv419a+SdfToKbFpvTLKaeOBy8RcdWL/MRMz6 sCOw2TtRt4fbFHp8vmFkf7+TpAUfgwnM0QXyltzhNborW6ZOH+pjVVFPBC7NG+CnIT6ckBI ClOqZ7YP37KA52Q8vxhGQ== X-UI-Out-Filterresults: notjunk:1; X-Original-Sender: Jens.Maurer@gmx.net X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of Jens.Maurer@gmx.net designates 212.227.17.20 as permitted sender) smtp.mail=Jens.Maurer@gmx.net 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:18655 Archived-At: On 06/18/2015 02:31 AM, Thiago Macieira wrote: > On Wednesday 17 June 2015 11:38:41 Matthew Woehlke wrote: >> On 2015-06-17 11:22, Matthew Fioravante wrote: >>> On Wednesday, June 17, 2015 at 10:55:06 AM UTC-4, Matthew Woehlke wrote: >>>> On 2015-06-17 10:31, Miro Knejp wrote: >>>>> I would say that 0/1 should suffice for bool in the basic version. >>>>> Maybe go as far as add two overloads each accepting two chars or two >>>>> strings for the true/false case. >>>> >>>> Accepting regex's would be better; that way you can say that true is >>>> e.g. "1|y(es)?|t(rue)?" (case insensitive), rather than being limited to >>>> exactly one accepted string. (Having faster overloads that take char or >>>> string literals is fine too, but if we have those, I would also have a >>>> regex overload.) >>> >>> I think thats an entirely different proposal. Adding regex support just >>> for >>> the small corner case of bool bloats the scope of this too much. >> >> Fair enough. On that note, however, I'm inclined to feel the same way >> about even having a bool parser. Do we *really* need that? It doesn't >> seem nearly as valuable as a numeric parser. > > We should have a bool parser if and only if std::is_integral::value. "bool" is an integral type. > It > should parse *numbers* from std::numeric_limits::min() to > std::numeric_limits::max(). So, that means 0 and 1. > I imagine that the front-end template interface would be something like: > > // skip bikeshedding about input, output and error > extern std::expected > parse_internal(const char *begin, const char *end, > uint64_t zero, uint64_t max, int base); > extern std::expected > parse_internal(const char *begin, const char *end, > int64_t min, int64_t max, int base); > > template > typename std::enable_if::value, > std::expected>::type > parse_number(std::string_view str, int base) > { > typedef typename std::conditional::value, > uint64_t, int64_t>::type Int64; > Int64 min = std::numeric_limits::min(); > Int64 max = std::numeric_limits::max(); > return parse_internal(str.begin(), str.end(), min, max, base); > } Signed vs. unsigned parsing is probably different enough (minus sign) that those two shouldn't be handled by the same function. Jens -- --- You received this message because you are subscribed to the Google Groups "ISO C++ Standard - Future Proposals" group. 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