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Daniel Cousineau
August 14, 2019
Programming
670
1
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Time is a Social Construct
Given at BrooklynJS, ManhattanJS, and JSConf 2019
https://www.youtube.com/watch?v=EUzPpXhFmG8
Daniel Cousineau
August 14, 2019
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Transcript
@dcousineau TIME IS A SOCIAL CONSTRUCT
@dcousineau SOCIAL CONSTRUCTS ARE GARBAGE
@dcousineau TIME IS GARBAGE
@dcousineau @dcousineau IS GARBAGE he/him
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau @dcousineau
@dcousineau 12pm Aug 15th, 2019
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau 12pm Aug 15th, 2019 UTC-0400
@dcousineau
@dcousineau 2019-08-15T12:00:00-0400
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau @dcousineau
@dcousineau
@dcousineau 2019-08-15T16:00:00Z
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau Daylight Savings Time @dcousineau
@dcousineau Sun, Mar 10 @ 2am to Sun, Nov 3
@ 2am
@dcousineau 2019-08-15T16:00:00Z 2019-11-04T16:00:00Z 12pm in New York 11am in New
York
@dcousineau
@dcousineau
@dcousineau Arizona is in the Mountain Timezone and does not
observe daylight savings time except in the Navajo Indian Nation.
@dcousineau
@dcousineau Standard DST
@dcousineau 2019-03-10T02:01:00-07:00 “Fun” Fact Quiz
@dcousineau 2019-03-10T02:01:00-07:00 “Fun” Fact Quiz
@dcousineau
@dcousineau @dcousineau
@dcousineau
@dcousineau @dcousineau
@dcousineau
@dcousineau @dcousineau
@dcousineau
@dcousineau
@dcousineau America/New_York EST America/Chicago CST America/Denver MST America/Phoenix MST …
@dcousineau America/Indiana/Indianapolis America/Indiana/Knox America/Indiana/Marengo America/Indiana/Petersburg America/Indiana/Tell_City America/Indiana/Vevay America/Indiana/Vincennes America/Indiana/Winamac
@dcousineau Maybe Wikipedia can help…
@dcousineau
@dcousineau
@dcousineau 1918–1961
@dcousineau 1961–1967
@dcousineau 1967–1977
@dcousineau 1977–1991
@dcousineau 1991–2006
@dcousineau 2006–March 2007
@dcousineau March 2007–November 2007
@dcousineau November 2007–Today
@dcousineau America/New_York: Dearborn & Ohio America/Chicago: Jasper, Lake, LaPorte, Newton,
Porter, Gibson, Posey, Spencer, Vanderburgh, & Warrick America/Kentucky/Louisville: Clark, Floyd, & Harrison Counties in Indiana NOT on America/Indiana/*
@dcousineau 2019-08-15T12:00:00-0400 America/New_York
@dcousineau
@dcousineau So… did we learn anything?
@dcousineau Treat time as if it is irreducibly complex.
@dcousineau Time is a question of where almost as much
as it’s when.
@dcousineau Treat UTC like it’s merely a synchronization and conversion
aid.
@dcousineau Always preserve presented offsets / timezones. Only clone &
convert into UTC if storage requires.
@dcousineau Use ISO-8601 in transit & let the browser handle
the rest. Treat it like a11y, give the browser / user control.
@dcousineau Be explicit about context with your user. If this
is confusing for you, it’s worse for them.
@dcousineau USE A LIBRARY! Especially for simple arithmetic. date-fns, moment.js,
Luxon
@dcousineau When all else fails, just move to Florida. ☀
@dcousineau fin.