From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=DKIM_ADSP_CUSTOM_MED, FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from primenet.com.au (ns1.primenet.com.au [203.24.36.2]) by inbox.vuxu.org (OpenSMTPD) with ESMTP id e932ff64 for ; Sat, 21 Dec 2019 21:07:08 +0000 (UTC) Received: (qmail 1509 invoked by alias); 21 Dec 2019 18:12:17 -0000 Mailing-List: contact zsh-workers-help@zsh.org; run by ezmlm Precedence: bulk X-No-Archive: yes List-Id: Zsh Workers List List-Post: List-Help: List-Unsubscribe: X-Seq: 45121 Received: (qmail 11343 invoked by uid 1010); 21 Dec 2019 18:12:17 -0000 X-Qmail-Scanner-Diagnostics: from mail-wr1-f48.google.com by f.primenet.com.au (envelope-from , uid 7791) with qmail-scanner-2.11 (clamdscan: 0.102.1/25663. spamassassin: 3.4.2. Clear:RC:0(209.85.221.48):SA:0(-2.0/5.0):. Processed in 0.742644 secs); 21 Dec 2019 18:12:17 -0000 X-Envelope-From: stephane.chazelas@gmail.com X-Qmail-Scanner-Mime-Attachments: | X-Qmail-Scanner-Zip-Files: | Received-SPF: pass (ns1.primenet.com.au: SPF record at _netblocks.google.com designates 209.85.221.48 as permitted sender) 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:subject:message-id:mail-followup-to :references:mime-version:content-disposition:in-reply-to:user-agent; bh=V4Doyyk5rwHGHcPR2pD3p+2exmHCwUH0VKr5l6SpGdk=; b=orKm212z2DG+LMd3vLG86L0h29Za/EgXxJhOJXliMwq4CRFT4zFrNz+czk7H8Ff/yd CWCuMAF40ZwAZzMbAMtRSrTFfx6xBKM/FWov7oikBCR+VwA+zLlLxb8klDklN2l6jdzl mClVOaoJlUMg2zn1Zd61iaQDlkOxugYkZWNvhQQaX5mgoOmdiqCnT5Z3JbBVa563gcvC jkZ+FSxluz2QIN2YFuNodkZJv/6a1NfgjJZt5/XAhzdA61pKKgoVoDNud0yGvSVOpEeB 2kEo333LrexLFNVxvYjB8zUqAIFbV5qe6sijuDixlHtN9x69kjqvjsoUqjp27Gx3waZB Y8pg== X-Gm-Message-State: APjAAAV+1cRVhrzwZVI7aiDZ7SfqGXOIsws7IGKnzbMwr0yIK+FH75Z9 pXWee2AnF8m9HsCcakxVp18= X-Google-Smtp-Source: APXvYqwt7VSMNTtQhmwskBIeg+6yOFyiGsaVhSjs732r5Py+NeWK8loxPFTX4bl9iq/AGr9mFU6gPQ== X-Received: by 2002:adf:fe43:: with SMTP id m3mr22391159wrs.213.1576951902657; Sat, 21 Dec 2019 10:11:42 -0800 (PST) Date: Sat, 21 Dec 2019 18:11:41 +0000 From: Stephane Chazelas To: Roman Perepelitsa , Zsh hackers list Subject: Re: zsh converts a floating-point number to string with too much precision Message-ID: <20191221181141.wy4ndiq6qyznod22@chaz.gmail.com> Mail-Followup-To: Roman Perepelitsa , Zsh hackers list References: <20191220013711.GA708801@zira.vinc17.org> <20191220165824.ufvjtx37xt7dp2dt@chaz.gmail.com> <20191221005005.GB767822@zira.vinc17.org> <20191221084736.bokldw7tzxw3thn3@chaz.gmail.com> <20191221175618.oolvw72n26tir2wg@chaz.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191221175618.oolvw72n26tir2wg@chaz.gmail.com> User-Agent: NeoMutt/20180716 2019-12-21 17:56:18 +0000, Stephane Chazelas: > 2019-12-21 10:43:43 +0100, Roman Perepelitsa: > [...] > > There is no simple algorithm that achieves this. I recall reading long > > papers a few years back that were describing various inventions in > > this field. They were pretty scary. > > https://github.com/openjdk/jdk/blob/f4af0eadb6eaf9d9614431110ab7fc9c1588966d/src/java.base/share/classes/jdk/internal/math/FloatingDecimal.java#L424 > is not exactly trivial. I enjoyed reading the comments even if I > have not clue what the the code is doing. [...] Microsoft's STL implementation (to_chars) looks about as hairy: https://github.com/microsoft/STL/blob/264b0d4a167daa9e5499af6d783c9ff22f7af03f/stl/inc/charconv -- Stephane