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WAT JavaScript Date

C4ce16f549c450f4759eb37f5d5d1a63?s=47 othree
August 10, 2017
Programming
3
1.5k

WAT JavaScript Date

C4ce16f549c450f4759eb37f5d5d1a63?s=128

othree

August 10, 2017
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Transcript

  1. .(6a6&;YGU]6]? S]EY??

  2. 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

  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. // 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

  25. // 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");

  26. // 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
  27. None

  28. // Firefox var theday = new Date(2017, 2, 3, 0,

    0, 0, 0);

  29. // Firefox var theday = new Date(2017, 2, 3, 0,

    0, 0, 0); // Date 2017-03-02T16:00:00.000Z
  30. None

  31. // Firefox var theday = new Date(2017, 2, 3, 0,

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

  32. // 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

  33. // 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

  34. // 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

  35. // 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

  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. [[_?[ 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=

  40. (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]?

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

  42. (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

  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. 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

  47. 6]E 㗢 ==㖏OSQ]E]S㖎㘍㖐㖎

  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. // 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();

  52. // 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"

  53. // 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"

  54. (GO?4SQ? 㗢 *(]GO?;E6QC?[㖎ES_YASYd6Y=6Q=96;Kd6Y= ;SYY?[USQ=GQC]S6㖎㙐ES_Y=GAA?Y?Q;?GQO?6Q[SM6Y]GO? ASY?a?Yh㖎㖒=?CY??[ https://www.timeanddate.com/time/time-zones.html

  55. (GO?4SQ? 㗢 [G6㘍69_M 㚗㖍㖑㗣㖐㖍

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

  57. 6hMGCE]&6aGQC(GO? 㗢 ۃႌͧ⯇ႏᯒ߭ॶ⤼౟î৩჋ 㗢 ᘔ৫ʼnଋᡦႫ 㗢 ἥῲᡦႫ᫨≡ᙩᖵ⇖

  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. (GO?4SQ?6]696[? 㗢 9h6aG=M[SQ 㗢 SdSU?Y6]?[9h 㗢 ?AGQG]GSQSA6]GO?jSQ? 㗢 6O?[SA]GO?jSQ?[ 㗢

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

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

  64. S;6MGj6]GSQ 㗢 㖏㖍㖎㖔㘍㖍㖔㘍㖍㖖㙐(6Gd6Q 㗢 㖍㖔㘍㖍㖖㘍㖏㖍㖎㖔㙐*& 㗢 㖍㖖㘍㖍㖔㘍㖏㖍㖎㖔㙐SYS;;S 㗢 㖍㖖㗿㖍㖔㗿㖏㖍㖎㖔㙐?YO6Q 㗢

    㖍㖖㙐㖍㖔㙐㖏㖍㖎㖔㙐_];E 㗢 ٠٩㘍٠٧㘍٢٠١٧㙐Y69G;

  65. 6M?Q=6Y[ 㗢 Y?CSYG6Q6M?Q=6Y 㗢 Ⱑᄞ㘶_Q6Y6M?Q=6Y㘹 㗢 ᒧڳᄞ 㗢 [M6OG;6M?Q=6Y

  66. G9Y6Yh]S]E?$?[;_?

  67. G9Y6YG?[

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

  69. None

  70. SO?Q]㗿I[ 㗢 _MMA_Q;]GSQ=6]?]GO?MG9Y6Yh 㗢 &_UUSY][㗣 㗢 U?YGS=㗦=_Y6]GSQ 㗢 ]GO?jSQ?㘵]j=9㘸 㗢

    G㖎㖕Q㘵dSYKGQCSQ$㘸
  71. None

  72. =6]?㙐AQ[ 㗢 *[?A_MA_Q;]GSQ[]SdSYKdG]E6]?S9I?;] 㗢 S=_M6YGj?=[O6MMA_Q;]GSQ[ 㗢 OO_]69M? 㗢 G㖎㖕Q

  73. import addMonths from 'date-fns/add_months' var thedate = new Date(2017, 0,

    31); addMonths(thedate, 2);
  74. None

  75. I[㙐IS=6 㗢 6a6S=6㙐(GO? GOUM?O?Q]6]GSQSQ6a6&;YGU] 㗢 9I?;]96[?= =?[GCQ

  76. 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

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

  81. (S Gf6a6&;YGU] 㗢 S]69M?]S;E6QC?SM=[]_AA 㗢 Y?6]?Q?d]EGQC[G[㘵6MOS[]㘸SK 㗢 Y?6]?6Q?d6]? 

  82. ]?OUSY6M

  83. ]?OUSY6M 㗢 ?dUYSUS[6M 㗢 S=6MGK? =?[GCQ 㗢 6CCG? GQ]㘵G;YS[SA]㘸 㗢

    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. ]?OUSY6M 㗢 &;YGU]&]6C?㖎 㗢 Q6;]Ga?=?a?MSUO?Q]QSd 㗢 I[㙐IS=6MGK? 㘵ASYQSd㘸 㗢 QG]E_9

  86. ?6]_Y?[ 㗢 㖎96[?=OSQ]E 㗢 OO_]69M? 㗢 (GO?jSQ?[_UUSY] 㗢 ?]]?Y 

  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. (E6QK[