From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp2 ([2001:41d0:2:bcc0::]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) by ms0.migadu.com with LMTPS id qLatB0iDaGAnKgAAgWs5BA (envelope-from ) for ; Sat, 03 Apr 2021 17:01:28 +0200 Received: from aspmx1.migadu.com ([2001:41d0:2:bcc0::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp2 with LMTPS id ONAxAkiDaGDiTwAAB5/wlQ (envelope-from ) for ; Sat, 03 Apr 2021 15:01:28 +0000 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by aspmx1.migadu.com (Postfix) with ESMTPS id 6923F201E3 for ; Sat, 3 Apr 2021 17:01:27 +0200 (CEST) Received: from localhost ([::1]:40484 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lShm9-0000I8-Ko for larch@yhetil.org; Sat, 03 Apr 2021 11:01:25 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:56312) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lShli-0000HT-NL for emacs-orgmode@gnu.org; Sat, 03 Apr 2021 11:00:58 -0400 Received: from se13.route25.eu ([2a00:f10:121:a00:1c00:efff:fe00:1854]:52788) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lShlc-0005PH-A6 for emacs-orgmode@gnu.org; Sat, 03 Apr 2021 11:00:56 -0400 Date: Sat, 3 Apr 2021 17:00:42 +0200 From: Russell Adams To: emacs-orgmode@gnu.org Subject: Re: Idea for handling timezones Message-ID: <20210403150042.GK27597@maokai> Mail-Followup-To: emacs-orgmode@gnu.org References: <647187.1617449014@apollo2.minshall.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <647187.1617449014@apollo2.minshall.org> X-Originating-IP: 185.87.185.80 X-SpamExperts-Domain: out.pcextreme.nl X-SpamExperts-Username: 185.87.185.80 X-SpamExperts-Outgoing-Class: ham X-SpamExperts-Outgoing-Evidence: Combined (0.09) X-Recommended-Action: accept X-Filter-ID: Pt3MvcO5N4iKaDQ5O6lkdGlMVN6RH8bjRMzItlySaT9qlN4ZJaODNn5X5ZmyTGl7PUtbdvnXkggZ 3YnVId/Y5jcf0yeVQAvfjHznO7+bT5xiExUbNqvmdkLSOzf1W2Y3z8hkeSqZT0W1YMl0fRDa99cV PSoHm0W/3adFfiYl2nvypRA8PF3Xa/U59fJjcHIT/T4GcPvCLvSpAEEGy7kYxsD3QRUnhlexiXT3 xXuXeIhevFP+kOiMW3ZJfjMJYMEj+gaXrHkgRC7/tI3CjXmVyngL9jTJEMnADDafZFBNiT/Hh0cQ L0Ci0sRm4Wh/iZxmZw2OUofLfB7s8QYvnn3mfsztdQUSqk/AeLi65+4s/LrywTM2yEHEhvC9Izsy /NENTMQ3Kg3hL2oXz5A5E5R/dS4GkJ5hfB+qWugfDEytZYoACfRtBjLzEjgIZNLWhI/Mshn3T8Ox KyIrAogwLlirll+u0Sc2bgjgy6NE5WzPnrJ1fJyKyenPq733oZ8bAyJmHQrtppYmxMktfUX7kfB+ UdezYqxGMqsKjARq8PBC4qgxMmglBiLsgrvXOb7qEGUwgxHIagHkgJmlqPNWnLI1oovhSJcbnX/H QqL/X9rNCJCc6iESJvKm1NV8gkr+Wu8ScVDXinOVyuIpITQ9z3M3DO7OWuqF1+w/pTOKTb9S094O 5ldb4EwDPpdfe0QRwC0uzSgMs/eLfzib/0rU6y+QowQMhGLnlae9783wi2Y8aEXin8trLB1aNUk3 bKYC3mDyT854kXwv2RX/MHp3a7oN/i32EoSnB0KQ6B3xt8UP9IrQLp/miaSDdXxJiAZb1EzkA9VQ u12rxRZzC8qBatCnapyU3iJFJGqv2qLHU+dz7c6OIlocJjhH4nOOlAJyaVPGctgzcDoFd+96Xw4Q UNtTnT5USTuJ4+3886sgmKmkaUBIi2jULgpXi1xBXhUizdxdDneFtYF4v0IUhnwA7zUt/xXczwGF xR7aC6zIFLawTOmNvxgu6jFRoaLzVpT+CP36s6RbLfB6BI3XJUys1lM3IMGhDC7qKEsgLqHNXMxe jlB49DjiWowOnKvI8aF4jzAuZNIARVagEMhjyGL5llQ69151eclHOr67cHgLgz4Hvn0= X-Report-Abuse-To: spam@semaster01.route25.eu Received-SPF: pass client-ip=2a00:f10:121:a00:1c00:efff:fe00:1854; envelope-from=rladams@adamsinfoserv.com; helo=se13.route25.eu X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-orgmode@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "General discussions about Org-mode." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-orgmode-bounces+larch=yhetil.org@gnu.org Sender: "Emacs-orgmode" X-Migadu-Flow: FLOW_IN ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1617462087; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references:list-id:list-help:list-unsubscribe: list-subscribe:list-post; bh=cIy8wK5c+FiaVgFh/to8oYxfIorDyI8YZM0B7a9fJ0c=; b=aBu57AydLSWoEKIgtbNYwTyvulNZ75JzzF/Mf8xQOUZbkNfbkTb/uoa39aPu9wptk1oE/F WH77/uFZXEXoF9LaV1wifLf7bgQBurnDm7o2VdZMn4Juc8PamSrj6hWZzWgo1qt1A90uHz JcylURTgGl3K35YbBG/ySSTt1ZHHpxX/sDjPEpP/HdGGqshiFEO0Wyt7Ql5ReJYzDqV/Nu jxWFx9jcnAWaj/6hSqh7QoDap+NtyFCQHyEeD5jprDZsnp2BVqrIEJbnLKh+kUZAhtKdbL u50Cyrk7r5Hy+Mxxk2l1UOKwiUZ/mIN3NTxRBRbfKs8feBLXjHj3bVV9ue4Lpw== ARC-Seal: i=1; s=key1; d=yhetil.org; t=1617462087; a=rsa-sha256; cv=none; b=GX3Bd0gb56qK0KrUra7sGPHSWhyS5pN2DTTk0b3X/NnIw09xULquOEamGddGJxJ4+Z45Fx ntBca8Vx93aU5MYAz3CvAtEBwC5Ge+NR9mWFhjADqEsGyRTbVcAwriAPZBqBrU2aTwrMxq 6F742rq1nVEm2y0EMf/Nrp2AATttUzjMH4fz8iQQCUZuMbhbA4rjald7sy96EHIAQE3CG1 pCzWP8o9UzTKUwmwLRglQBPWVXKtBfHEPRM+Jedo6IWNkNuzcJLYXzJAzTz6YZ8qNcUpIr hjzhn6mGLyFuRmmP5xzdgoHEU4irNmA/TdPv8KVDnM+8wvFth9HXdCn519Iiuw== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=none; spf=pass (aspmx1.migadu.com: domain of emacs-orgmode-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=emacs-orgmode-bounces@gnu.org X-Migadu-Spam-Score: -1.93 Authentication-Results: aspmx1.migadu.com; dkim=none; dmarc=none; spf=pass (aspmx1.migadu.com: domain of emacs-orgmode-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=emacs-orgmode-bounces@gnu.org X-Migadu-Queue-Id: 6923F201E3 X-Spam-Score: -1.93 X-Migadu-Scanner: scn0.migadu.com X-TUID: yqcF7cwbiAtD On Sat, Apr 03, 2021 at 02:23:34PM +0300, Greg Minshall wrote: > > #+TIMEZONE: America/Toronto > > > > at the start of their org file, and they moved to Shanghai, all the timestamp in > > the org file is converted using something equivalent to I think what you're saying here is that timestamps without timezone information should have a default timezone. I'd suggest there is a global default setting (ie: init file), and allow a buffer local override. Essentially all timestamps that don't specify a timezone should fall back to the local TZ, unless there's a buffer override. I'd be in favor of revisiting the idea of putting timezone information into the timestamp. I know it's a deep change, but this is a kind of incremental growth we should expect to a core feature. I frequently fight this issue myself with meetings across timezones. I would not suggest using UTC. I believe one of the reasons timestamps didn't include TZ information was to keep them short and human legible. Solutions with overlays to change a timestamp reduce the usefulness of the plain text reading of Org (ie: less, grep, etc). Storing timestamps with UTC is really a shortcut for the computer, not the user. I was just reading about Emacs' parse-time-string function, and Emacs already has TZ conversion built in to many of the time functions. It seems to me that we could fall back to the Emacs parser if needed. https://www.gnu.org/software/emacs/manual/html_node/elisp/Time-Parsing.html Today's timestamps are in the form of "YYYY-MM-DD Day HH:MM". I've often wondered that the day name is in there, other than for human legibility. Given timestamps are always wrapped in <> or [], for active and inactive timestamps accordingly, parsing for a new element at the end by time zone name doesn't sound so bad. Staying with user friendly, I think time zone names would be more useful than delta syntax from UTC. [2021-04-03 Sat 16:56 CEST] doesn't sound too bad, given the timezones aren't expected to be in every timestamp. I really think that the key issue making adoption difficult will be all the tooling reading these, not the timestamps themselves. ------------------------------------------------------------------ Russell Adams RLAdams@AdamsInfoServ.com PGP Key ID: 0x1160DCB3 http://www.adamsinfoserv.com/ Fingerprint: 1723 D8CA 4280 1EC9 557F 66E8 1154 E018 1160 DCB3