From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nick Dokos Subject: Re: Time-zone in dates Date: Mon, 29 Jun 2015 21:17:55 -0400 Message-ID: <87egkugfjw.fsf@pierrot.dokosmarshall.org> References: <87zj3moadx.fsf@gmail.com> <87zj3mv9rb.fsf@ucl.ac.uk> <87ioaav72g.fsf@ucl.ac.uk> <87y4j6tgyn.fsf@nicolasgoaziou.fr> <20150626195749.GG5090@fjo-extia-HPdeb> <87zj3iodr4.fsf@ucl.ac.uk> Mime-Version: 1.0 Content-Type: text/plain Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:60928) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z9kBd-000441-7d for emacs-orgmode@gnu.org; Mon, 29 Jun 2015 21:18:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z9kBY-0003Yk-R4 for emacs-orgmode@gnu.org; Mon, 29 Jun 2015 21:18:09 -0400 Received: from plane.gmane.org ([80.91.229.3]:39845) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z9kBY-0003Yb-KS for emacs-orgmode@gnu.org; Mon, 29 Jun 2015 21:18:04 -0400 Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1Z9kBX-00025r-Gz for emacs-orgmode@gnu.org; Tue, 30 Jun 2015 03:18:03 +0200 Received: from pool-108-20-41-47.bstnma.fios.verizon.net ([108.20.41.47]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 30 Jun 2015 03:18:03 +0200 Received: from ndokos by pool-108-20-41-47.bstnma.fios.verizon.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 30 Jun 2015 03:18:03 +0200 List-Id: "General discussions about Org-mode." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org Sender: emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org To: emacs-orgmode@gnu.org Eric S Fraga writes: > On Friday, 26 Jun 2015 at 21:57, francois@avalenn.eu wrote: > > [...] > >> It is really simpler programmatically to deal with time offsets >> instead. The downside is that you cannot manage DST and other similar >> peculiarities but the API is much simpler to write. > > Time offsets are not sufficient. My Australia experience involved me > living in South Australia while working with colleagues in the UK. The > time difference throughout the year was one of 8.5 hours, 9.5 hours or > 10.5 hours, depending on the various switches to and from daylight > savings. Very annoying and confusing to manage... > > To be effective and usable, org will need to incorporate time zone > information. The only reliable way of doing that is to use UTC as the "internal" representation and translate to/from local time on external display/input *only*. In the case of org mode, the "internal" representation is user-visible, so that can cause confusion and some head-scratching. But *any* other method is going to be a nightmare (damhikt). -- Nick