new Date コンストラクターDate 関数 (JavaScript)[6] Date を構築子としてではなく関数として呼ぶと、
ES3 的には引数で表される日時の Date を文字列化したものが返ってくるはずですが、
Firefox、Chrome、Opera、WinIE8 のいずれも引数を無視して現在日時を表す文字列を返すようです。
Date 型 (Web IDL)[12] DOMTimeStamp、DOMHighResTimeStamp
のように数値として日時を表す型もあります。
[1] 15.9 Date オブジェクト (Date Objects) ( 版) http://www2u.biglobe.ne.jp/~oz-07ams/prog/ecma262r3/15-9_Date_Objects.html
[4] B 互換性 (Compatibility) ( 版) http://www2u.biglobe.ne.jp/%7Eoz-07ams/prog/ecma262r3/B_Compatibility.html#section-B.2
[2] 閏秒には対応していません。 ES3 15.9.1.1
[3] mozilla mozilla/js/src/jsdate.c ( 版) http://mxr.mozilla.org/mozilla/source/js/src/jsdate.c
[5] Date - MDC ( 版) https://developer.mozilla.org/ja/Core_JavaScript_1.5_Reference/Global_Objects/Date
[8] [whatwg] Timing API proposal for measuring intervals ( ( 版)) http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2011-July/032343.html
[17] Web Applications 1.0 r8094 Revert r8083, since it leads to weird behaviour worse than just returning a new object each time. (It seems this isn't implemented by anyone yet anyway.) ( ( 版)) http://html5.org/tools/web-apps-tracker?from=8093&to=8094
[18] Web Applications 1.0 r8113 Change startDate to a method to avoid the confusion of it being mutable. ( ( 版)) http://html5.org/tools/web-apps-tracker?from=8112&to=8113
[19] IRC logs: freenode / #whatwg / 20130731 ( ( 版)) http://krijnhoetmer.nl/irc-logs/whatwg/20130731
[20] Bug 22824 – Remove Date from WebIDL ( ( 版)) https://www.w3.org/Bugs/Public/show_bug.cgi?id=22824
[21] Java8日付時刻APIの使いづらさと凄さ - きしだのはてな ( ( 版)) http://d.hatena.ne.jp/nowokay/20130917#1379376320
[22] File API | lastModified and Date attribute change ( (Arun Ranganathan 著, 版)) http://lists.w3.org/Archives/Public/public-webapps/2013OctDec/0662.html
[23] HTML date format and Date.parse() ( ( 版)) https://mail.mozilla.org/pipermail/es-discuss/2013-April/030412.html
[24] Emotion Markup Language (EmotionML) 1.0 ( ( 版)) http://www.w3.org/TR/emotionml/#s2.4.2.1
[25] RFC 3507 - Internet Content Adaptation Protocol (ICAP) ( ( 版)) http://tools.ietf.org/html/rfc3507#section-4.3.1
[26] Merge pull request #342 from martinthomson/issue324 · w3c/webrtc-pc@05909f7 ( 版) https://github.com/w3c/webrtc-pc/commit/05909f7d33c0dca829816c3ca47b93a593fb9fc6
[27] Close #279: stop using IDL Date so it can be removed from IDL · whatwg/html@260b66f ( 版) https://github.com/whatwg/html/commit/260b66f352b34143c29bf3b2f5a17f9b5c34c1e1
[28] 22824 – Remove Date from WebIDL ( 版) https://www.w3.org/Bugs/Public/show_bug.cgi?id=22824
[29] Breaking: refactor structured clone into serialize/deserialize (domenic著, ) https://github.com/whatwg/html/commit/97d644c97335956610a31e8ad98d1a388c063e84
[30] API Reference - Web Application - Tizen Web Device API Reference - System - Time API | Tizen Developers () https://developer.tizen.org/development/api-references/web-application?redirect=https://developer.tizen.org/dev-guide/3.0.0/org.tizen.web.apireference/html/device_api/mobile/tizen/time.html
new Date("1969-12-31T23:59:59.999+01:00").toJSON();
// OK! => "1969-12-31T22:59:59.999Z"
new Date("1969-12-31T23:59:59.999-01:00").toJSON();
// NG! => "1970-01-01T00:59:59.998Z"
[32] "object getStartDate()" should be "Date getStartDate()" · Issue #3340 · whatwg/html () https://github.com/whatwg/html/issues/3340
[33] ECMAScript® 2020 Language Specification () https://tc39.github.io/ecma262/#sec-date-constructor
[34] Dateオブジェクト (日付と時刻) | JavaScript プログラミング解説 () https://so-zou.jp/web-app/tech/programming/javascript/grammar/object/date.htm