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.(6a6&;YGU]6]? S]EY??

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O? 㗢 S]EY??SQQ]?YQ?] 㗢 E]]U[㗣㘍㘍9MSC㗿S]EY??㗿Q?] 㗢 .?9&]6Q=6Y= SMMSd?Y㗦 YSQ]?Q= QCGQ??Y 㗢 &* 㗦&㗦&㗦 㗿㗿㗿

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.(6a6&;YGU]6]?

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.(6a6&;YGU]6]?

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“Wat” is a variant of the English word “what” that is often used to express confusion or disgust, much like its better known acronym “WTF,” short for “what the fuck.” http://knowyourmeme.com/memes/wat

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0.1 + 0.2

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0.1 + 0.2 // 0.30000000000000004

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https://www.destroyallsoftware.com/talks/wat

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.(6a6&;YGU]6]?

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// Firefox latest new Date("2005-07-08");

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// Firefox latest new Date("2005-07-08"); // Date 2005-07-08T00:00:00.000Z

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// Firefox latest new Date("2005-07-08"); // Date 2005-07-08T00:00:00.000Z new Date("2005/07/08");

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// Firefox latest new Date("2005-07-08"); // Date 2005-07-08T00:00:00.000Z new Date("2005/07/08"); // Date 2005-07-07T16:00:00.000Z

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// Firefox latest new Date("2005-07-08"); // Date 2005-07-08T00:00:00.000Z // July 8th 00:00 UTC new Date("2005/07/08"); // Date 2005-07-07T16:00:00.000Z // July 8th 00:00 local time

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// Firefox latest new Date("2005-07-08"); // Date 2005-07-08T00:00:00.000Z // July 8th 00:00 UTC new Date("2005/07/08"); // Date 2005-07-07T16:00:00.000Z // July 8th 00:00 local time (Date.parse("2005-07-08") - Date.parse("2005/07/08")) / 36e5 // 8 hours

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// Firefox latest new Date("2005-07-08"); // Date 2005-07-08T00:00:00.000Z // July 8th 00:00 UTC new Date("2005/07/08"); // Date 2005-07-07T16:00:00.000Z // July 8th 00:00 local time (Date.parse("2005-07-08") - Date.parse("2005/07/08")) / 36e5 // 8 hours // Chrome latest new Date("2005-07-08");

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// Firefox latest new Date("2005-07-08"); // Date 2005-07-08T00:00:00.000Z // July 8th 00:00 UTC new Date("2005/07/08"); // Date 2005-07-07T16:00:00.000Z // July 8th 00:00 local time (Date.parse("2005-07-08") - Date.parse("2005/07/08")) / 36e5 // 8 hours // Chrome latest new Date("2005-07-08"); // Fri Jul 08 2005 08:00:00 GMT+0800 (CST) // July 8th 00:00 local time

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// Firefox var theday = new Date(2017, 2, 3, 0, 0, 0, 0);

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// Firefox var theday = new Date(2017, 2, 3, 0, 0, 0, 0); // Date 2017-03-02T16:00:00.000Z

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// Firefox var theday = new Date(2017, 2, 3, 0, 0, 0, 0); // Date 2017-03-02T16:00:00.000Z // 2 -> March, 0 based

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// Firefox var theday = new Date(2017, 2, 3, 0, 0, 0, 0); // Date 2017-03-02T16:00:00.000Z // 2 -> March, 0 based // UTC Time: 03/02 16:00 // UTC+8 Time: 03/03 00:00

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// Firefox var theday = new Date(2017, 2, 3, 0, 0, 0, 0); // Date 2017-03-02T16:00:00.000Z // 2 -> March, 0 based // UTC Time: 03/02 16:00 // UTC+8 Time: 03/03 00:00 theday.getDate() // 3 theday.getUTCDate() // 2

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// Firefox var theday = new Date(2017, 2, 3, 0, 0, 0, 0); // Date 2017-03-02T16:00:00.000Z // 2 -> March, 0 based // UTC Time: 03/02 16:00 // UTC+8 Time: 03/03 00:00 theday.getDate() // 3 theday.getUTCDate() // 2 new Date(2017, 2, 3, 8, 0, 0, 0); // Date 2017-03-03T00:00:00.000Z

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// Firefox var theday = new Date(2017, 2, 3, 0, 0, 0, 0); // Date 2017-03-02T16:00:00.000Z // 2 -> March, 0 based // UTC Time: 03/02 16:00 // UTC+8 Time: 03/03 00:00 theday.getDate() // 3 theday.getUTCDate() // 2 new Date(2017, 2, 3, 8, 0, 0, 0); // Date 2017-03-03T00:00:00.000Z new Date(Date.UTC(2017, 2, 3, 8, 0, 0, 0)); // Date 2017-03-03T08:00:00.000Z

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var d = new Date(2016, 12, 31); d.setMonth(d.getMonth() + 1); d.toISOString();

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new Date('0'); new Date(0); new Date(0, 0); new Date(0, 0, 0);

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[[_?[ 㗢 Y?CSYG6Q;6M?Q=6YSQMh 㗢 _]69M?㗦 SSY =?[GCQ 㗢 㖍96[?=OSQ]E 㗢 *Q?fU?;]?=U6Y[?Y9?E6aGSY 㗢 S(GO?4SQ?6Q=&([_UUSY] 㗢 S=_Y6]GSQ㗦U?YGS=

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(E?6]?9I?;] 㗢 S;E6QC?[GQ;?6a6&;YGU]㖎㗿㖍 㗢 6[?=SQ6a6㖎9?]66]㖎㖖㖖㖒 㗢 I6a6㗿_]GM㗿6]?

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https://twitter.com/BrendanEich/status/481939099138654209

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(E?6]?  㗢 S;E6QC?[GQ;?6a6&;YGU]㖎㗿㖍 㗢 6[?=SQ6a6㖎9?]66]㖎㖖㖖㖒 㗢 I6a6㗿_]GM㗿6]? 㗢 6a6㖎㗿㖍Y?M?6[?=6]6Q㖎㖖㖖㖓 㗢 ?UY?;6]?=6MOS[]?Q]GY?6]?GQ6a6㖎㗿㖎6] ?9㖎㖖㖖㖔

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https://www.cs.princeton.edu/courses/archive/fall97/cs461/jdkdocs/relnotes/deprecatedlist.html

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https://www.cs.princeton.edu/courses/archive/fall97/cs461/jdkdocs/relnotes/deprecatedlist.html

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6]?㛱(GO?

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6]?㛱(GO? 㗢 ?6Uh?6Y㗦M?6U[?;SQ= 㗢 (GO?jSQ? 㗢 6M?Q=6Y[ 㗢 &( 㗢 6]E 㗢 S;6MGj6]GSQ

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6]E 㗢 ==㖏OSQ]E]S㖎㘍㖐㖎

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// momentjs var thedate = moment("20170131", "YYYYMMDD");

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// momentjs var thedate = moment("20170131", "YYYYMMDD"); thedate.add(2, 'months').format();

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// momentjs var thedate = moment("20170131", "YYYYMMDD"); thedate.add(2, 'months').format(); // "2017-03-31T00:00:00+08:00"

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// momentjs var thedate = moment("20170131", "YYYYMMDD"); thedate.add(2, 'months').format(); // "2017-03-31T00:00:00+08:00" thedate.add(1, 'months').add(1, 'months').format();

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// momentjs var thedate = moment("20170131", "YYYYMMDD"); thedate.add(2, 'months').format(); // "2017-03-31T00:00:00+08:00" thedate.add(1, 'months').add(1, 'months').format(); // "2017-03-28T00:00:00+08:00"

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// momentjs var thedate = moment("20170131", "YYYYMMDD"); thedate.add(2, 'months').format(); // "2017-03-31T00:00:00+08:00" thedate.add(1, 'months').add(1, 'months').format(); // "2017-03-28T00:00:00+08:00" thedate.add(1, 'months').format(); // "2017-02-28T00:00:00+08:00"

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(GO?4SQ? 㗢 [G6㘍69_M 㚗㖍㖑㗣㖐㖍

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(GO?4SQ? 㗢 [G6㘍69_M 㚗㖍㖑㗣㖐㖍 㗢 [G6㘍6]O6Q=_ 㚗㖍㖒㗣㖑㖒

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6hMGCE]&6aGQC(GO? 㗢 ۃႌͧ⯇ႏᯒ߭ॶ⤼౟î৩჋ 㗢 ᘔ৫ʼnଋᡦႫ 㗢 ἥῲᡦႫ᫨≡ᙩᖵ⇖

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// moment.js moment.tz("2014-02-09T02:30", "US/Pacific").format() // "2014-02-09T02:30:00-08:00"

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// moment.js moment.tz("2014-02-09T02:30", "US/Pacific").format() // "2014-02-09T02:30:00-08:00" moment.tz("2014-03-09T02:30", "US/Pacific").format() // "2014-03-09T03:30:00-07:00"

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// moment.js moment.tz("2014-02-09T02:30", "US/Pacific").format() // "2014-02-09T02:30:00-08:00" moment.tz("2014-03-09T02:30", "US/Pacific").format() // "2014-03-09T03:30:00-07:00" // Daylight Saving Time

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https://time.is/en/PT

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https://www.iana.org/time-zones

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G9Y6YG?[

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G9Y6YG?[ 㗢 SO?Q]㗿I[ 㗢 =6]?㙐AQ[ 㗢 I[㙐IS=6

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import addMonths from 'date-fns/add_months' var thedate = new Date(2017, 0, 31); addMonths(thedate, 2);

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S=6㙐(GO? 㗢 9h&]?UE?QSM?9S_YQ?6]㖏㖍㖍㖏 㗢 ć၏Ŕ„ 㗢 CSSCM?㗣㘍㘍ᆱȍ⍝S=6

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var thedate = LocalDate.parse('2017-01-31').atStartOfDay(); var after2m = thedate.plusMonths(2); after2m.toString(); // "2017-03-31T00:00" var sixtydays = Duration.ofDays(60); thedate.plus(sixtydays).toString(); // "2017-04-01T00:00" ZonedDateTime.now(ZoneId.of('Europe/Paris')).toString(); // "2017-02-04T17:01:15.846+01:00[Europe/Paris]"

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(Sd6Y=]S Gf 6a6&;YGU]6]?

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(S Gf6a6&;YGU] 㗢 S]69M?]S;E6QC?SM=[]_AA 㗢 Y?6]?Q?d]EGQC[G[㘵6MOS[]㘸SK

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]?OUSY6M

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https://github.com/tc39/proposal-temporal

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?6]_Y?[ 㗢 㖎96[?=OSQ]E 㗢 OO_]69M? 㗢 (GO?jSQ?[_UUSY] 㗢 ?]]?Y 

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SY?SQ;?U][ 㗢 Q[]6Q] 㗢 ?YGS= 㗢 _Y6]GSQ

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var ldt = new temporal.LocalDateTime(2017, 12, 31, 23, 59); var addHours = new temporal.LocalDateTime( 2017, 12, 31, 23, 00).add(2, 'hours'); var zdt = new temporal.ZonedDateTime('America/New_York', 2017, 12, 31, 23, 59);

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var ldt = new CivilDateTime(2017, 12, 31, 23, 59); var addHours = new CivilDateTime(2017, 12, 31, 23, 00) .add(2, 'hours'); var zdt = ldt.withZone(‘America/New_York');

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(E6QK[