新しい要素の提案

[2] Aural Cascading Style Sheets (ACSS) http://www.w3.org/TR/WD-acss-970630#speech-properties

This ('speak-date' property) would be most useful when combined with a new HTML tag used to identify dates, such as this theoretical example:

   <p>The campaign started on <date value="1874-oct-21">
   the twenty-first of that month</date> and finished 
   <date value="1874-oct-28">a week later</date>

[16] W3C I18N FAQ: Date formats (2007-05-20 22:36:46 +09:00 版) http://www.w3.org/International/questions/qa-date-format#bytheway

Some have advocated the creation of a <date> tag that would display dates according the locale of the user agent. This is subject to the same practical issues as described for dynamic date generation with the Japanese example. The appropriate format is generally a function of the linguistic context of a page, rather than the user's platform.

既存要素の流用

[63] マイクロフォーマット界隈では、 abbr 要素を日時の表記に流用する 「デザイン・パターン」を発明しました。 (詳しくは abbr の項を参照してください。)

[62] Tantek's Thoughts (Tantek Çelik 著, 2006-05-20 00:13:35 +09:00 版) http://tantek.com/log/2005/01.html#d26t0100

My first instinct was to try the <object> tag, since it has a nice mechanism for providing data within its 'data' attribute, and fallback plain text inside the element itself, e.g. (simplified for sake of discussion):

<object data="20050125">January 25</object>

This worked great in typical modern browsers, except for one: Safari (v1.2.1). Unfortunately, to put it mildly, Safari's <object> support sucks. It doesn't handle <object> fallbacks, it doesn't know when not to handle <object> mime types that it doesn't support, it doesn't support display:inline on <object>, and it doesn't do proper intrinsic sizing of <object> replaced elements. These are all trivial to reproduce bugs.

Humans don't think of dates and times in terms of fully qualified year, month, date, hour, minute, second, time-zone values. Humans think of dates and times in terms of only that which is necessary. The day, or the day and the month, or perhaps just the hour. What do all these have in common? They are all abbreviations for a fully qualified date and time.

Lucky for us, XHTML has an element for abbreviations: <abbr>.

Thus, the ISO8601 date 20050125 should be marked up as:

<abbr title="20050125">January 25th</abbr>

• [38] abbr design pattern - Microformats Wiki, 2022-10-08T16:56:50.000Z, 2024-08-17T13:11:16.197Z http://microformats.org/wiki/abbr-design-pattern

[64] しかしこれに対しては「abbr は略語を表すが、日時は略語ではない」 などの批判があり、マイクロフォーマット界隈を越えて普及するには至りませんでした。

t 要素

[3] Ian Hickson は、日時を表す要素の追加の要求が古くから強いことを踏まえ、 t 要素を HTML5 仕様案に追加しました。

[45] <t> element, draft the first., Hixie, 2006-10-26 17:23:51 +09:00, 2024-09-01T10:28:43.000Z https://github.com/whatwg/html/commit/6bdcd9dc9da3f21cb61f0f8c123ed2d252cd2583

[5] 現地時間が記述されていても、 tooltip で利用者の地方時が表示されるようなブラウザにwktk (名無しさん 2006-09-25 23:41:07 +00:00)

[6] [whatwg] Joe Clark's Criticisms of the WHATWG and HTML 5 http://listserver.dreamhost.com/pipermail/whatwg-whatwg.org/2006-October/007513.html (名無しさん 2006-10-31 00:54:15 +00:00)

[7] >>6 [whatwg] Joe Clark's Criticisms of the WHATWG and HTML 5 (2009-03-09 12:00:26 +09:00 版、 Ian Hickson 著) http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2006-October/007513.html

<t> (or an equivalent) has been widely requested, especially in the microformats and CSS communities. Several microformats have need for encoding specific times and/or dates, and are currently (ab?)using <abbr> for this purpose. The CSS community has requested a <date> or <time> element because they want to restyle dates and times according to locale. The blogging and content publishing communities have also raised the need for a way to unambiguously mark up what part of their document is a date and/or time, though in their case (as with microformats) they need a way to then mark each date/time element as being a particular semantic (publishing date, birth date, calendar event time etc).

Also, the aforementioned research indicated that there are substantial amounts of content on the Web that uses invented elements, IDs, and class attributes to mark up dates and times. For example, I found about the same number of pages with the obscure ID "updatedtime" as I did pages with a <button> element; "date" was the 14th most frequently seen class name.

time 要素 (第1世代)

[8] 「t」は短すぎるということで、後に time に改められました。

• [46] <t> becomes <time>, Hixie, 2006-11-23 10:56:14 +09:00, 2024-09-01T12:16:09.000Z https://github.com/whatwg/html/commit/fdfe6548265125712520f3e1b72812235e9a8123#diff-41cf6794ba4200b839c53531555f0f3998df4cbb01a4d5cb0b94e3ca5e23947d
• [49] xref scripting is enabled / scripting is disabled; define 'text node'…, Hixie, 2006-11-26 14:51:15 +09:00, 2024-09-01T12:21:42.000Z https://github.com/whatwg/html/commit/afc04cb92c239fdf03db01751379817cdc7ae725#diff-41cf6794ba4200b839c53531555f0f3998df4cbb01a4d5cb0b94e3ca5e23947d

[17] Sam Ruby: The <time> element (2007-04-19 08:32:25 +09:00 版) http://www.intertwingly.net/blog/2007/04/17/The-time-element (名無しさん 2007-04-18 23:39:35 +00:00)

[76] [whatwg] <time> element feedback ( (2010-12-08 08:42:59 +09:00 版)) http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2010-December/029363.html

[67] [whatwg] proposal: extend <time> to markup durations ( (2011-07-30 04:20:12 +09:00 版)) http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2011-July/032456.html

time 要素 (第2世代)

[90] 2011年10月に time 要素は削除され、かわりに data 要素が導入されました。11月に新たに time 要素が追加されました。 (data 要素も残っています。)

[91] 第1世代の time 要素は Webブラウザーに相応のレンダリングを求めるものでしたが、 実際には著者は独自のレンダリングを望んでおり、Webブラウザーも独自のレンダリングを実装する意思がないことから、 同名の新しい要素を改めて定義しなおしたものだと説明されています。

[92] しかしこの変更への反発から W3C HTML WG を中心に大きな混乱が生じ、 それまで WHATWG の HTML5 の複製だった W3C の HTML5 に独自の変更が加えられ、それをきっかけに両者が同期されなくなりました。 W3C の HTML5 はこの騒動の後しばらく放置されていましたが、最終的には W3C が独自の編集者を雇用し、 WHATWG と決別して独自の仕様書を発行するようになります。

• [69] Web Applications 1.0 r6783 Drop <time> and replace it with <data>. Drop the Atom conversion section entirely. Convert a bunch of examples that used to use <time pubdate> to using schema.org, to show how to annotate publication dates and the like in a machine-processable way. ( (2011-10-29 14:38:00 +09:00 版)) http://html5.org/tools/web-apps-tracker?from=6782&to=6783
  • [50] [acgiowt] (2) Drop <time> and replace it with <data>. Drop the Atom c…, Hixie, 2011-10-29 14:38:56 +09:00, 2024-09-06T13:38:19.000Z https://github.com/whatwg/html/commit/70b0ce45a26937a3f26eeb72b146261ff6210a1d

[51] 13240 – Consider replacing <time> with <data>, 2019-04-02T04:48:11.000Z, 2024-09-06T13:38:33.958Z https://www.w3.org/Bugs/Public/show_bug.cgi?id=13240

[70] IRC logs: freenode / #whatwg / 20111102 ( (2011-11-05 12:41:15 +09:00 版)) http://krijnhoetmer.nl/irc-logs/whatwg/20111102

[71] IRC logs: freenode / #whatwg / 20111102 ( (2011-11-05 12:41:15 +09:00 版)) http://krijnhoetmer.nl/irc-logs/whatwg/20111102

[72] HTML5 spec reverted to cvs r1.5431, svn r6782 [was: Revert request for r6783] ( (Michael[tm] Smith 著, 2011-11-11 03:06:27 +09:00 版)) http://lists.w3.org/Archives/Public/public-html/2011Nov/0098.html

[73] IRC logs: freenode / #whatwg / 20111110 ( (2011-11-12 00:39:03 +09:00 版)) http://krijnhoetmer.nl/irc-logs/whatwg/20111110

[74] IRC logs: freenode / #whatwg / 20111111 ( (2011-11-12 00:43:00 +09:00 版)) http://krijnhoetmer.nl/irc-logs/whatwg/20111111

[75] Ian Hickson responds over HTML5 getting 'time' element back | News | .net magazine (2011-11-12 01:05:16 +09:00 版) http://www.netmagazine.com/news/ian-hickson-responds-over-html5-getting-time-element-back-111552

[77] Time element - WHATWG Wiki ( (2011-11-06 10:06:26 +09:00 版)) http://wiki.whatwg.org/wiki/Time_element

• [78] Web Applications 1.0 r6827 the <time> element is dead, long live the <time> element ( (2011-11-19 04:43:00 +09:00 版)) http://html5.org/tools/web-apps-tracker?from=6826&to=6827
  • [53] [acgiowt] (1) the <time> element is dead, long live the <time> element, Hixie, 2011-11-19 04:43:57 +09:00, 2024-09-06T13:44:04.000Z https://github.com/whatwg/html/commit/92baa8333203ea5b97316bb1775331b216d55dab#diff-41cf6794ba4200b839c53531555f0f3998df4cbb01a4d5cb0b94e3ca5e23947d

[79] Web Applications 1.0 r6829 extend timezone format to also allow omitting the colon ( (2011-11-19 08:22:00 +09:00 版)) http://html5.org/tools/web-apps-tracker?from=6828&to=6829

[80] (3) Google ( (2011-11-19 13:57:07 +09:00 版)) https://plus.google.com/107429617152575897589/posts/3ZEQAVkF6xd

[81] IRC logs: freenode / #whatwg / 20111116 ( (2011-11-18 00:23:14 +09:00 版)) http://krijnhoetmer.nl/irc-logs/whatwg/20111116

[82] IRC logs: freenode / #whatwg / 20111118 ( (2011-11-20 12:06:23 +09:00 版)) http://krijnhoetmer.nl/irc-logs/whatwg/20111118

[83] IRC logs: freenode / #whatwg / 20111129 ( (2011-11-29 08:57:16 +09:00 版)) http://krijnhoetmer.nl/irc-logs/whatwg/20111129

[84] IRC logs: freenode / #whatwg / 20111206 ( (2011-12-07 08:32:57 +09:00 版)) http://krijnhoetmer.nl/irc-logs/whatwg/20111206#l-1112

[85] [whatwg] proposal: extend <time> to markup durations (2011-12-07 09:36:37 +09:00 版) http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2011-December/034091.html

[86] Web Applications 1.0 r6845 Update the date-and-time microsyntaxes to support having the 'T' replaced by a single space. (Note: multiple spaces are invalid and will cause parse failures. Only a single space is supported.) Based on proposal and implementation evidence from Tantek documented at http://wiki.whatwg.org/wiki/Time_element#permit_space_instead_of_T_in_datetimesAffected topics: HTML, Microdata ( (2011-12-07 08:00:00 +09:00 版)) http://html5.org/tools/web-apps-tracker?from=6844&to=6845

[87] [whatwg] proposal: extend <time> to markup durations ( (2011-12-09 08:14:18 +09:00 版)) http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2011-December/034091.html

[88] Web Applications 1.0 r7435 Make the year-only format for <time> more in line with how it works elsewhere. ( (2012-10-06 07:50:00 +09:00 版)) http://html5.org/tools/web-apps-tracker?from=7434&to=7435