OT: ODF 1.2 Review - handling dates

["Dennis E. Hamilton" <dennis.hamilton@acm.org>]



Just an indication that we are not alone in scratching our head over this sort of thing.  I can't find the definition of [GREGORIAN] in the HTML 5 working draft, and not sure they even mention [ISO 8601].

 

I'm not sure how this text will come through on the list.  If the material below is mangled, try the URL of the blog post,

http://blog.whatwg.org/this-week-in-html-5-episode-11 

 - Dennis

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From: Mark Pilgrim, Google [mailto:mark@diveintomark.org]  

Posted At: Monday, November 03, 2008 08:29
Posted To: The WHATWG Blog
Conversation: This Week in HTML 5 - Episode 11
Subject: This Week in HTML 5 - Episode 11

Welcome back to "This Week in HTML 5," where I'll try to summarize the major activity in the ongoing standards process in the WHATWG and W3C HTML Working Group. Last Friday was Halloween for some of you; in the United States, it involves dressing up in slutty costumes, begging your neighbors for handouts, and getting diabetes. Yesterday, many of you set your clocks back one hour for Daylight Savings Time. And for those of you on the Gregorian calendar, it is now November.

Dates and times loom large in this week's updates. "What is today's date?" is a deceptively simple question, matched in complexity only by the related question, "What time is it?" Sources for Time Zone and Daylight Saving Time Data gives a good overview of the current state of the art for answering both questions. In the movie Crocodile Dundee, Mick says he once asked an Aboriginal elder when he was born; the elder replied, "in the summertime."

r2381 defines global dates and times:

A global date and time consists of a specific Gregorian date, consisting of a year, a month, and a day, and a time, consisting of an hour, a minute, a second, and a fraction of a second, expressed with a time zone, consisting of a number of hours and minutes.

r2382 defines local dates and times:

A local date and time consists of a specific Gregorian date, consisting of a year, a month, and a day, and a time, consisting of an hour, a minute, a second, and a fraction of a second, but expressed without a time zone.

r2383 defines a month:

A month consists of a specific Gregorian date with no timezone information and no date information beyond a year and a month.

r2384 and r2385 define a week:

A week consists of a week-year number and a week number representing a seven day period. Each week-year in this calendaring system has either 52 weeks or 53 weeks, as defined below. A week is a seven-day period. The week starting on the Gregorian date Monday December 29th 1969 (1969-12-29) is defined as week number 1 in week-year 1970. Consecutive weeks are numbered sequentially. The week before the number 1 week in a week-year is the last week in the previous week-year, and vice versa.

A week-year with a number year that corresponds to a year year in the Gregorian calendar that has a Thursday as its first day (January 1st), and a week-year year where year is a number divisible by 400, or a number divisible by 4 but not by 100, has 53 weeks. All other week-years have 52 weeks.

The week number of the last day of a week-year with 53 weeks is 53; the week number of the last day of a week-year with 52 weeks is 52.

Note: The week-year number of a particular day can be different than the number of the year that contains that day in the Gregorian calendar. The first week in a week-year year is the week that contains the first Thursday of the Gregorian year year.

<input> form elements can be declared to take a local date and time, a global date and time, a date, a time, a month, or a week. You can also declare a global date and time in a <time> element or in the datetime attribute of <ins> and <del>.

HTML 5 does not define weekends or holidays, and therefore does not define business days. Interstellar datekeeping has been pushed back to HTML 6.

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