Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.lang.python > #96449

Re: Are there any "correct" implementations of tzinfo?

Path csiph.com!eternal-september.org!feeder.eternal-september.org!feeds.phibee-telecom.net!newsfeed.xs4all.nl!newsfeed8.news.xs4all.nl!nzpost1.xs4all.net!not-for-mail
Return-Path <random832@fastmail.us>
X-Original-To python-list@python.org
Delivered-To python-list@mail.python.org
X-Spam-Status OK 0.019
X-Spam-Evidence '*H*': 0.96; '*S*': 0.00; 'conversions': 0.07; 'matches': 0.07; 'received:internal': 0.09; 'times,': 0.13; 'message-id:@webmail.messagingengine.com': 0.16; 'opposite': 0.16; 'received:10.202': 0.16; 'received:10.202.2': 0.16; 'received:10.202.2.212': 0.16; 'received:66.111': 0.16; 'received:66.111.4': 0.16; 'received:messagingengine.com': 0.16; 'timezones': 0.16; 'unambiguous': 0.16; 'wrote:': 0.16; 'sep': 0.22; 'subject:skip:i 10': 0.22; 'sat,': 0.23; 'header:In-Reply- To:1': 0.24; "doesn't": 0.26; 'mostly': 0.27; 'correct': 0.28; "i'm": 0.30; 'implement': 0.32; 'problem': 0.33; 'definition': 0.34; 'clear': 0.35; 'possible': 0.36; 'subject:" ': 0.36; 'to:addr:python-list': 0.36; 'subject:?': 0.36; 'subject:: ': 0.37; 'received:10': 0.37; 'really': 0.37; '12,': 0.37; 'times.': 0.38; 'received:66': 0.38; 'to:addr:python.org': 0.40; 'from:no real name:2**0': 0.60; 'your': 0.60; 'header:Message-Id:1': 0.61; 'times': 0.63; 'subject:there': 0.66; 'talking': 0.67; 'meyer': 0.84; 'subject:any': 0.84; 'subject:Are': 0.95
DKIM-Signature v=1; a=rsa-sha1; c=relaxed/relaxed; d=fastmail.us; h= content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-sasl-enc :x-sasl-enc; s=mesmtp; bh=1tKaVH5f/30csXwDkrF1MQv6Zb8=; b=UQW8yr EawArL23EPSj6gE7vuxvZZw39EUD5yE+MuzPIdtAUlan7kSZc5d/qWwjfayHFiBq qdT+EfT/DFVTfyjFZowHttnnIMnAt2sL1ongPB2TfOkJi37x6pDqOgdPeBvG5bgD WKU9bocrWTEajQRmrfIHI5aqfAcQsAAQRwOcU=
DKIM-Signature v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-sasl-enc:x-sasl-enc; s=smtpout; bh=1tKaVH5f/30csXw DkrF1MQv6Zb8=; b=egTJ7XL3RQw5kh9/n+PyRMM2xxA17JFpGmuUUcpRGDIgIaf AYCaFopQVu8OyNM8SPiVuHZyJ/45z4mYxPP58awa6MFjKp43tZ+Bha+S5nWZh04E QWome4DCByf0E0xOtylduKQcHYz2n1sewwsGBO+n+5DyAgaE/xGuIj3+F660=
X-Sasl-Enc ZvlCm7raDbE+9G2c0tzbcs6aDFS3T5xqigXR9CFP4QWy 1442085539
From random832@fastmail.us
To python-list@python.org
MIME-Version 1.0
Content-Transfer-Encoding 7bit
Content-Type text/plain
X-Mailer MessagingEngine.com Webmail Interface - ajax-c76b43ce
Subject Re: Are there any "correct" implementations of tzinfo?
Date Sat, 12 Sep 2015 15:18:59 -0400
In-Reply-To <55F47098.80706@oddbird.net>
References <m2h9mzqyy7.fsf@fastmail.com> <55F47098.80706@oddbird.net>
X-BeenThere python-list@python.org
X-Mailman-Version 2.1.20+
Precedence list
List-Id General discussion list for the Python programming language <python-list.python.org>
List-Unsubscribe <https://mail.python.org/mailman/options/python-list>, <mailto:python-list-request@python.org?subject=unsubscribe>
List-Archive <http://mail.python.org/pipermail/python-list/>
List-Post <mailto:python-list@python.org>
List-Help <mailto:python-list-request@python.org?subject=help>
List-Subscribe <https://mail.python.org/mailman/listinfo/python-list>, <mailto:python-list-request@python.org?subject=subscribe>
Newsgroups comp.lang.python
Message-ID <mailman.439.1442085541.8327.python-list@python.org> (permalink)
Lines 11
NNTP-Posting-Host 2001:888:2000:d::a6
X-Trace 1442085541 news.xs4all.nl 23756 [2001:888:2000:d::a6]:49497
X-Complaints-To abuse@xs4all.nl
Xref csiph.com comp.lang.python:96449

Show key headers only | View raw


On Sat, Sep 12, 2015, at 14:36, Carl Meyer wrote:
> Well, the problem is that because datetime doesn't include any way to
> disambiguate ambiguous times, it's not really possible to implement
> complex timezones in a way that is both correct (if your definition of
> correct includes "timezone conversions are lossless") and also matches
> the intended model of datetime.

I'm not even talking about ambiguous times. I'm mostly talking about
unambiguous times on opposite sides of the transition. It's not even
clear to me how the model of datetime envisions _those_ working with
"classic arithmetic".

Back to comp.lang.python | Previous | Next | Find similar | Unroll thread


Thread

Re: Are there any "correct" implementations of tzinfo? random832@fastmail.us - 2015-09-12 15:18 -0400

csiph-web