From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp12.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 sHkyHGnIxWP2MQAAbAwnHQ (envelope-from ) for ; Mon, 16 Jan 2023 22:58:01 +0100 Received: from aspmx1.migadu.com ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp12.migadu.com with LMTPS id 0ES2G2nIxWNSPgAAauVa8A (envelope-from ) for ; Mon, 16 Jan 2023 22:58:01 +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 100FD3AD6B for ; Mon, 16 Jan 2023 22:58:00 +0100 (CET) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pHXTk-0005vh-1Y; Mon, 16 Jan 2023 16:57:20 -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 1pHXTj-0005vY-0d for emacs-orgmode@gnu.org; Mon, 16 Jan 2023 16:57:19 -0500 Received: from mailbackend.panix.com ([166.84.1.89]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pHXTh-0003UN-Km for emacs-orgmode@gnu.org; Mon, 16 Jan 2023 16:57:18 -0500 Received: from quad (panix1.panix.com [166.84.1.1]) by mailbackend.panix.com (Postfix) with ESMTPS id 4Nwm8W6YDQz45Dd; Mon, 16 Jan 2023 16:57:15 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=panix.com; s=panix; t=1673906236; bh=n0fivjxcrsLZvZeiZqP3N4XekP5iyYycxmZeizneRYs=; h=References:From:To:Cc:Subject:Date:Reply-To:In-reply-to; b=SP0nz7LBQxOn2e1QZGxi3Y2Q7b3gCrt+XJZL8aVnLIbc7u64oKqNNFwzLMycNI3C/ GBUgjxtQz5n5awr+8LfoucNIC9bt/OibDGLYmcNeoftIlS0uDdexvUX09IMw3FGpaU ihqWtYuNVAICpKWJSKwnMYUEkYAJOILBLCu45TT0= References: <86zgamtv6o.fsf@gmail.com> <87tu0t1i0c.fsf@localhost> <63c2aa9e.170a0220.3bb49.9ef4@mx.google.com> <87pmbhz1x6.fsf@localhost> <87wn5mlo7f.fsf@localhost> <87pmbelnd0.fsf@localhost> <87fscajo2q.fsf@localhost> <87cz7ejmgu.fsf@localhost> User-agent: mu4e 1.8.1; emacs 28.1 From: Robert Horn To: Tom Gillespie Cc: emacs-orgmode@gnu.org, rjhorn@alum.mit.edu Subject: Re: [FEATURE REQUEST] Timezone support in org-mode datestamps and org-agenda Date: Mon, 16 Jan 2023 16:48:41 -0500 In-reply-to: Message-ID: MIME-Version: 1.0 Content-Type: text/plain Received-SPF: pass client-ip=166.84.1.89; envelope-from=rjhorn@panix.com; helo=mailbackend.panix.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, 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: 2.1.29 Precedence: list List-Id: "General discussions about Org-mode." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: rjhorn@alum.mit.edu 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-Seal: i=1; s=key1; d=yhetil.org; t=1673906281; a=rsa-sha256; cv=none; b=Two74hcj2s3CE0n2KF05BWJehzL3M7a/Zdjr0lEqCrdbfpCwvizpiUmqjXonsip831hoSD KC14EYm+1LTlr62yNaGFQPBe9HRXkFneabRqhaBorou9RZQDsHB/Ylv59FGMlp0XoboWhk IfTx1BJZwL2Eg02dch0ZYdbhZyIce3uRL4GNQTw7nr3OsM1MV5B1LVZ2Z4TVA93ZgGSeDH +sswwl+5XfsNHeUy18vjD8qw20qUow+an3PZZlHopXHfNW6FMsHspZUw/C2T/Cw4Lb2YrI 12a3z+j5RjHdSdEWcZLOOsZVacEF2pctsmOBde1v2FU+CaBZr97dyE2hTqmoog== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=fail ("headers rsa verify failed") header.d=panix.com header.s=panix header.b=SP0nz7LB; 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"; dmarc=fail reason="SPF not aligned (relaxed)" header.from=panix.com (policy=none) ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1673906281; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc: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:dkim-signature; bh=Q/Q2UMZ8RiSriBXldcevgADuy8sobwnujUSURYw6EVE=; b=HdwO9rPwe4ewM/nsRDWJ9Fq6J5x9BCc9JWC5Q7amc1PlcCZXROFqQz0AS0lnSQKywrZU9J iwJOaNALj/M6lCAPMLPzKgzUY19xjWOypkFh7j+U+HKZ17tedL+aeclxxgGdJOGz+2gRG5 nPCTuDayE0jMEbYDSK/c5IgMoUdXsyu/snYRUA2Qcs0c6mLt9c6Clz1GSuCRDv30LPaNG5 86VfY2fEyGgl+IoxJ8G7eZG+Hv2PEUKFyb6C3+ykR0fXakftwevA+re9m7lsi0kSahtplE 7TkngqpQE3ABIFHt+vdX602B6vtSIPaLDBt9j2i9TzNx+FAu+OpzSwhP35LF6w== X-Migadu-Spam-Score: -0.33 X-Spam-Score: -0.33 X-Migadu-Queue-Id: 100FD3AD6B X-Migadu-Scanner: scn1.migadu.com Authentication-Results: aspmx1.migadu.com; dkim=fail ("headers rsa verify failed") header.d=panix.com header.s=panix header.b=SP0nz7LB; 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"; dmarc=fail reason="SPF not aligned (relaxed)" header.from=panix.com (policy=none) X-TUID: e9/wnsg6dte4 Tom Gillespie writes: >> Getting the rules and explanation clear is the issue. It's a mistake >> that a great many people make with scheduling meetings. Those two >> behaviors need different encodings because they behave differently. > > This is related to why I suggested splitting timezones and offsets into > two separate categories. I think we have to assume that the written > content of timestamps in an org file cannot/will-not be changed > automatically. > The solution that we used in an operational scheduling system was to invent a new family of time zones, the "Then Local Time There". So you would schedule something like "10:05 TLT (NorthAmerica/New York)". This was the most commonly used scheduled time. It's what most people mean when they schedule something. Then the scheduled time encoding did not change, but the displayed time could. It was displayed in a format that met the needs of the users. When you're dealing with people in many locations you need to separate the concept of scheduled time in the org file from the concept of time display in a format useful to the user. Those who wanted astronomical or other relationships would usually specify UTC or TAI. They might use a fixed offset for UTC. People who are into the demands of TAI (e.g., orbital mechanics) generally don't want to deal with the offsets or other issues that come up with UTC, so they wanted TAI. -- Robert Horn rjhorn@alum.mit.edu