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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-Authentication-Results: i=1; aspmx1.migadu.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=q21DeF5X; 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=pass (policy=none) header.from=gmail.com ARC-Seal: i=1; s=key1; d=yhetil.org; t=1673675554; a=rsa-sha256; cv=none; b=dcgKK9MKfKYNq09TdiZKn2Shzf9kpRiwhuoXQk2NOMbfYktKWe221SkcAnFTcDFv7UGBpa gg75XDDRh7FUTfhRleEt8xwTIYXlaN3TjlY2UzwmNLW0UhkoaG0LtLGQTgkk4n4GvrwsX8 UkyoAo3n0ovVnY0TyovKdl+o5mrW6djMlZB8MTgAk19zLSXbEnkcy1rtRILh3eBu4DAoUy D+eIdoITHZFIw25vggm+zmrROsH6XjAyo4f/W/M3kw6TNEoeQ/I7m50tS/nnz1uVbM/ZfW LQonmSta0HORDAPyVFDqS6I9wV3BROHgwlCPyABRuASdoK5bMEb86/LacmBmCA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1673675554; 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:dkim-signature; bh=179ZuMYI5fWd7cXlz9eepXI2U99uAde624IqO5CLoZI=; b=ogv8c2p4gzM6tOOzq8A8uhwkj/Cls80wKzUAhkU0VPulDRTo83xSRMt9Rzca6X1IIk9fNS VEq5c7vQCXPcTZGLbLlUohUvyb1d76ZGSVcMjlkC279ptFK1aToutc86/k8rOHJa/LbiuS r1lPMYR3M4q3DkbEntoWAQsW6C+66h9xXZacng7/goMNTz37VwB7Zcb4HsnBsSqLoYv/zq Z7hB+9GrQdjlKJPnXe8dJ+UfK1gUnwr5MVDKOiceBLVxu4z/5IkaNtMzvSb8Yt+EUtc9k/ Wodo+L1kmQvcHipJaXw9XCafdlBSSiTWjH2RdiOc6BPyJi3m4+2YUEW3yRY+zw== X-Migadu-Queue-Id: B3CFAEC38 X-Migadu-Scanner: scn0.migadu.com Authentication-Results: aspmx1.migadu.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=q21DeF5X; 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=pass (policy=none) header.from=gmail.com X-Migadu-Spam-Score: -7.85 X-Spam-Score: -7.85 X-TUID: m6Lo3QEFEhYh Without wading too far into this at the moment, timezones are an extremely tricky problem with a whole bunch of design considerations. I am reproducing the heading comment from laundry's timestamp.rkt in its entirety here. Best! Tom https://github.com/tgbugs/laundry/blob/master/laundry/grammar/timestamp.rkt ; the org spec is currently silent on how org will handle dates beyond ; 0000 and 9999, the relevant standards for expanded representations ; are ISO 8601-1:2019,5.2.2.3 and ISO 8601-2:2019,8.4.3. The problem ; with expanded representations is that they require all parties to ; agree ahead of time how wide the year is and prefix with + and ; leading zeros, I am not sure that this is as robust as we would like ; 0000-01-01 is january first of the year zero, -0001-01-01 is jan ; first of the year 1BCE, and +10000-01-01 for jan 1 of 10000CE 5 ; digits must be prefixed by the plus sign, the standard is not ; entirely clear, but I think that we could do PLUS digits HYPHEN ; or DIGIT-4 HYPHEN and everything would work out ; on a separate but related note, org timestamps are always in local ; time and do not currently support timezones, which is a problem ; further absurdities that are related to the timezone issue: the ; date/time implementation as a text format completely fails if ; authoring on another planet ; given my objective to ensure that org documents can be interpreted ; without having to stick stupid things like #+planet: mars in the ; header or risk your earthling readers getting incorrect dates --- I ; suggest that org switch to storing all dates and times in earth zulu ; time or with an offset as it stands, the timezone setting of the ; computer drafting the document must be known to determine what day ; it was etc. users could still draft using <2020-12-16> but C-c C-c ; would add the correct offset? actually this is tricky, because there ; are two cases, one where the location is clear, "napoleon on [1812-01-01]" ; and the other where it is not, the issue is that a single date refers ; to as many different time intervals as there are timezones and without ; knowing the timezone you don't know the date, similar issue if we were ; to try to convert to sols ; https://www.eecis.udel.edu/~mills/missions.html ; https://www.eecis.udel.edu/~mills/ipin.html ; https://en.wikipedia.org/wiki/Timekeeping_on_Mars ; HOWEVER having applied a bit more brain power to the problem, let's ; just assume that clock synchonization will happen between earth and ; mars so that the unix epoch could be synchronized between the frames ; probably with multiple reference stations in free fall and/or in deep ; space to account for gravitaitonal differences etc. so actually the ; only issue would be a practical notational one, or a UI one, since we ; can use timestamp with timezone or just straight epoc for this to work ; earth vs martian year/day is a much harder issue ; the org spec is currently silent on how org will handle dates beyond