From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp11.migadu.com ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms5.migadu.com with LMTPS id aJFDBIYd52MrSwEAbAwnHQ (envelope-from ) for ; Sat, 11 Feb 2023 05:45:58 +0100 Received: from aspmx1.migadu.com ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp11.migadu.com with LMTPS id 0JdNBIYd52MTHQEA9RJhRA (envelope-from ) for ; Sat, 11 Feb 2023 05:45:58 +0100 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 AF3633082 for ; Sat, 11 Feb 2023 05:45:57 +0100 (CET) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pQhl5-0002zE-T6; Fri, 10 Feb 2023 23:45:07 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pQhl3-0002yk-Sv for emacs-orgmode@gnu.org; Fri, 10 Feb 2023 23:45:05 -0500 Received: from ciao.gmane.io ([116.202.254.214]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pQhl0-0006Wa-VE for emacs-orgmode@gnu.org; Fri, 10 Feb 2023 23:45:04 -0500 Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1pQhky-0000l2-Sc for emacs-orgmode@gnu.org; Sat, 11 Feb 2023 05:45:00 +0100 X-Injected-Via-Gmane: http://gmane.org/ To: emacs-orgmode@gnu.org From: Max Nikulin Subject: Re: [POLL] Proposed syntax for timestamps with time zone info (was: [FEATURE REQUEST] Timezone support in org-mode datestamps and org-agenda) Date: Sat, 11 Feb 2023 11:44:54 +0700 Message-ID: References: <87lelce6iu.fsf@localhost> <87357i9959.fsf@localhost> <877cwse95m.fsf@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.7.1 Content-Language: en-US In-Reply-To: Received-SPF: pass client-ip=116.202.254.214; envelope-from=geo-emacs-orgmode@m.gmane-mx.org; helo=ciao.gmane.io X-Spam_score_int: 17 X-Spam_score: 1.7 X-Spam_bar: + X-Spam_report: (1.7 / 5.0 requ) BAYES_00=-1.9, DKIM_ADSP_CUSTOM_MED=0.001, FORGED_GMAIL_RCVD=1, FORGED_MUA_MOZILLA=2.309, FREEMAIL_FORGED_FROMDOMAIN=0.249, FREEMAIL_FROM=0.001, HEADER_FROM_DIFFERENT_DOMAINS=0.248, NICE_REPLY_A=-1.149, NML_ADSP_CUSTOM_MED=0.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-orgmode@gnu.org X-Mailman-Version: 2.1.29 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-bounces+larch=yhetil.org@gnu.org X-Migadu-Country: US X-Migadu-Flow: FLOW_IN ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1676090757; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=nlXwMu5U/wP4fQNGIYWQph+rwuh06JNpa1FkDzNYX8Y=; b=JuiRU6yZ4IcL0YYvA0oIqRDRdPCSyecG6R3dFhnwUdPGAXunRgwD/2GwDjDvi5ipVXmQtT Rq5DFbOf9cF3SEfsEACSBaA+YdIj/XRBw85kMDSWzE2DWvIwmxy9ImGTvi/rP33N0lPNj0 kdX+Gpi29LxrnEvIkybgpjOhzKXuhqks96wI4B1nQGz+IUd138/UVpuwBMC7L12U8zA6Nl PBJnslYyCyuBPZ3VLdgp44B0Y5j6O/O/HnZlZgVpKw93bA1fRKOIMbEmmEpsAnP6hS6IuS nRtIlaz4KTmGLxYl06hzGXRaQ1wuFvEISejrvqQYRKEl1TcYL7TRQbMyPeqUBw== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=none; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=gmail.com (policy=none); spf=pass (aspmx1.migadu.com: domain of "emacs-orgmode-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="emacs-orgmode-bounces+larch=yhetil.org@gnu.org" ARC-Seal: i=1; s=key1; d=yhetil.org; t=1676090757; a=rsa-sha256; cv=none; b=b92JAudAD4kOT8U36D1Q3CXz4f9kr8XjyhwR0gQgmyMbBQob37PInJ8GmFfxkAbnIobjAL /43gTSNVLB3Wg7hBsCWaya//430SXuzPpbFoCCPHMaNs2P1rViBUzgvfEeiL8S9pqBbrI5 3yxV2RQjmRzLoT2NGzACEB3xa7B2uyrXcWOA5ylK38bbfutPnzay5Vu+HnjpZ1BCc4zkuy wDIgGM/wROPEaqbj8wkUuyYcoTNDOGLijry5zoRhRe7sXf4f1GNYMgJ9A6GWA4/5pDCKaA gIJRbvLpvPu3VUIdrBzFoMk7xYD70XLKTZY095FM2Y7ATGtOSbu5YTR9gR/0gw== Authentication-Results: aspmx1.migadu.com; dkim=none; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=gmail.com (policy=none); spf=pass (aspmx1.migadu.com: domain of "emacs-orgmode-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="emacs-orgmode-bounces+larch=yhetil.org@gnu.org" X-Migadu-Spam-Score: -2.30 X-Spam-Score: -2.30 X-Migadu-Queue-Id: AF3633082 X-Migadu-Scanner: scn1.migadu.com X-TUID: +ooi8tsfOod+ On 10/02/2023 10:29, Jean Louis wrote: > 2030-02-09 12:00 -08 @UTC -- this time CANNOT be said to be "fixed > UTC" I do not see any reason why obviously invalid timestamp draws so much attention. Resolution may be rather concise: behavior is *undefined* since field values are mutually inconsistent. Perhaps implementation may prefer to treat it as 2030-02-09T12:00:00-0800 discarding UTC as time zone specifier. `org-lint' should issue a warning requesting a user action. Could you explain what is wrong with the following (without timezone)? 2030-02-09 12:00 -0800 I consider it as an unambiguous equivalent of 2030-02-09T20:00:00Z that is a UTC timestamp. The format with explicit offset may be convenient for a person living in an area that *likely* will have -08:00 offset and who would like to watch some astronomical event such as lunar eclipse and who had a plan to connect to some telescope on the opposite side of the globe. Event time will not change if local time changed. Both variants 2030-02-09T12:00:00-0800 and 2030-02-09T20:00:00Z may be presented as "2030-02-09 12:00" to users. If timezone offset is changed both variants will converted to "13:00" or "11:00" depending on sign of change. So the format with offset is human friendly because it gives a hint concerning *probable* value of local time still remaining *precise* in respect to UTC. I find the following as acceptable, but confusing to some degree: 2030-02-09 12:00 -08 just because "-08" is currently used in TZ database as time zone abbreviation (a string similar to "BST"), not as offset that is represented in wide spread formats as -0800 or -08:00. Unfortunately the latter causes ambiguity in the context of Org.