WAT JavaScript Date

1.

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

2.

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㗢 &* 㗦&㗦&㗦㗿㗿㗿

3.

.(6a6&;YGU]6]?

4.

.(6a6&;YGU]6]?

5.

“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

6.

0.1 + 0.2

7.

0.1 + 0.2 // 0.30000000000000004

8.

None

9.

None

10.

None

11.

None

12.

None

13.

None

14.

None

15.

None

16.

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

17.

.(6a6&;YGU]6]?

18.

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

19.

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

20.

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

21.

// 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

22.

None

23.

// 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

24.

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

25.

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");

26.

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

27.

None

28.

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

29.

0, 0, 0); // Date 2017-03-02T16:00:00.000Z

30.

None

31.

0, 0, 0); // Date 2017-03-02T16:00:00.000Z // 2 -> March, 0 based

32.

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

33.

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

34.

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

35.

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

36.

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

37.

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

38.

None

39.

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*Q?fU?;]?=U6Y[?Y9?E6aGSY 㗢 S(GO?4SQ?6Q=&([_UUSY] 㗢 S=_Y6]GSQ㗦U?YGS=

40.

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41.

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

42.

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㗢 ?UY?;6]?=6MOS[]?Q]GY?6]?GQ6a6㖎㗿㖎6] ?9㖎㖖㖖㖔

43.

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

44.

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

45.

6]?㛱(GO?

46.

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6]E 㗢 S;6MGj6]GSQ

47.

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48.

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

49.

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

50.

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

51.

"2017-03-31T00:00:00+08:00" thedate.add(1, 'months').add(1, 'months').format();

52.

"2017-03-31T00:00:00+08:00" thedate.add(1, 'months').add(1, 'months').format(); // "2017-03-28T00:00:00+08:00"

53.

"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"

54.

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55.

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56.

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57.

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58.

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

59.

// 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"

60.

// 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

61.

https://time.is/en/PT

62.

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6hMGCE][6aGQC]GO?㘵&(㘸Y_M?[ 㗢 ?6U[?;SQ=

63.

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

64.

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㖍㖖㙐㖍㖔㙐㖏㖍㖎㖔㙐_];E 㗢 ٠٩㘍٠٧㘍٢٠١٧㙐Y69G;

65.

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66.

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67.

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68.

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69.

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70.

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71.

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72.

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73.

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

74.

None

75.

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76.

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77.

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]"

78.

None

79.

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

80.

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81.

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82.

]?OUSY6M

83.

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6]]SEQ[SQ㘵G;YS[SA]㗦6_]ESYSASO?Q]㗿I[㘸㗢 YG6Q(?YM[SQ㘵G;YS[SA]㘸

84.

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

85.

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86.

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87.

SY?SQ;?U][ 㗢 Q[]6Q] 㗢 ?YGS= 㗢 _Y6]GSQ

88.

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);

89.

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');

90.

(6K?_] 㗢 6]?㗦]GO?G[;SOUM?f 㗢 6a6&;YGU]6]?G[9YSK?Q 㗢 SSY 㗦QS]GO?jSQ?㗦M6;KSA;SQ;?U][ 㗢 *[?MG9Y6YG?[
㗢 ?MUAGfG]㘵]?OUSY6M㘸

91.

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WAT JavaScript Date

WAT JavaScript Date

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