1211 2005-04-05 10:15:18 +0000 [F&O] Midnight (24:00:00) 2005-09-29 10:39:38 +0000 1 1 1 Unclassified XPath / XQuery / XSLT Functions and Operators 1.0 Last Call drafts PC Windows XP CLOSED FIXED P2 normal --- 1 mike ashok.malhotra public-qt-comments oldest_to_newest 3803 0 mike 2005-04-05 10:15:18 +0000 Section 10.4 needs to discuss how midnight (24:00:00) is handled. I believe the correct treatment is that when filling in values from the reference date time, the value 24:00:00 is considered to be the same as 00:00:00 on the following day. Thus if the reference date is 1972-12-31, the time 24:00:00 expands to 1973-01-01T00:00:00, with the consequence that 24:00:00 and 00:00:00 are not equal. But the dateTimes 2005-04-04T24:00:00 and 2005:04-05:00:00:00 *are* equal. Michael Kay 3633 1 mike 2005-04-27 21:31:24 +0000 Please see a more extended discussion of the topic and a detailed proposal at http://lists.w3.org/Archives/Member/w3c-xsl-query/2005Apr/0053.html (Member-only) Michael Kay 3379 2 ashok.malhotra 2005-05-11 15:30:00 +0000 The WGS decided on 5-10-2005 to accept Mike Kay's proposal in http://lists.w3.org/Archives/Member/w3c-xsl-query/2005May/0004.html 3382 3 pcotton 2005-05-11 19:15:12 +0000 Since the URL given was member-only here is the details of the adopted proposal: === So here are the changes we need to make for the alternative proposal, which makes it represent the start of the day when used as a time, but the end of the day when used in a dateTime. This mainly consists of examples to alert people to the possible surprises that this causes. In the data model, add a note to 3.3.2 that the lexical representation "24:00:00" maps to the value (0,0,0), while 1999-12-31T24:00:00 maps to the value (2000, 1, 1, 0, 0, 0). In F+O: Section 5.2. Add two examples: fn:dateTime(xs:date("1999-12-31"), xs:time("12:00:00")) => xs:dateTime("1999-12-31T12:00:00") fn:dateTime(xs:date("1999-12-31"), xs:time("24:00:00")) => xs:dateTime("1999-12-31T00:00:00") with perhaps a word of explanation. Section 10.1: explain in the text or by examples that the lexical representation "24:00:00" maps to the value (0,0,0), while 1999-12-31T24:00:00 maps to the value (2000, 1, 1, 0, 0, 0). In 10.4, to the paragraph starting "The starting instant of an occurrence of a date/time value is an xs:dateTime calculated by filling in the missing components..." add: "If the xs:time value written as 24:00:00 is to be compared, filling in the missing components gives 1972-12-31T00:00:00, because 24:00:00 is treated as being simply an alternative representation of 00:00:00 (the lexical value 24:00:00 is converted to the components (0,0,0) before the missing components are filled in). This has the consequence that when ordering xs:time values, 24:00:00 is considered to be earlier than 23:59:59. However, when ordering xs:dateTime values, a time of 24:00:00 is considered equivalent to 00:00:00 on the following day." Section 10.4.7.1: add the examples op:dateTime-equal(xs:dateTime("1999-12-31T24:00:00"), xs:dateTime("2000-01-01T00:00:00")) returns true op:dateTime-equal(xs:dateTime("2005-04-04T24:00:00"), xs:dateTime("2005-04-04T00:00:00")) returns false Section 10.4.13: add the example op:time-equal(xs:time("24:00:00+01:00"), xs:time("00:00:00+01:00")) returns true Section 10.4.14: add the example op:time-less-than(xs:time("23:59:59"), xs:time("24:00:00")) return false Section 10.5.7: add the example fn:year-from-dateTime(xs:dateTime("1999-12-31T24:00:00")) returns 2000 Section 10.5.10: add the example fn:hours-from-dateTime(xs:dateTime("1999-12-31T24:00:00")) returns 0 Section 10.5.18: add the example fn:hours-from-time(xs:time("24:00:00")) returns 0 Section 10.8.3: add the example op:subtract-times(xs:time("24:00:00"), xs:time("23:59:59")) returns xdt:dayTimeDuration("-PT23H59M59S"), with an explanation as with the other examples. Section 17.1.2, to the paragraph starting "If ST is xs:dateTime, xs:date or xs:time, ..." add "Note that the hours component of the resulting string will never be 24. Midnight is always represented as "00:00:00". ===