3.3 KiB
The IANA timezone database is the official nomenclature for timezone information, and is what you should use, whenever possible.
Humans though, are goofballs, and use a whole different informal scheme.
- In (North) America, we use: PST, MST, EST...
- in Europe (lately) they use: WEST, CEST, EEST...
- in Africa they use: EAT, CAT, WAST...
- in Australia they use: AWST, AEDT, ACST...
these line-up with the IANA timezones sometimes. Other times they don't.
These names collide all the time, (like IST - irish/indian stardard time).
These names produce all-sorts of ambiguities, regarding DST-changes -
Both Winnipeg and Mexico City are CST, but have a much different DST schedule:
(thanks timeanddate.com!)
Of course, there's a bunch of political/historical/disputed stuff going on, too. Apologies if I step into this unknowingly.
This library is an attempt to 'soften' this exchange, between human-IANA, using some opinionated-but-common-sense rules and decision-making.
It was built for use in the spacetime timezone library, but may be used without it.
const informal = require('spacetime-informal')
informal.find('EST')
// 'America/New_York'
informal.find('central')
// 'America/Chicago'
informal.find('venezuela')
// 'America/Caracas'
informal.find('south east asia')
// 'Asia/Bangkok'
informal.display('Toronto')
/*{
standard: { name: 'Eastern Standard Time', abbrev: 'EST' },
daylight: { name: 'Eastern Daylight Time', abbrev: 'EDT' },
iana: 'Canada/Toronto'
}*/
it was built to be as forgiving as possible, and return the most common-sense IANA timezone id from user-input.
along with spacetime, you can generate human-friendly time formats, like this:
const spacetime = require('spacetime')
const informal = require('spacetime-informal')
let display = informal.display('montreal')
let s = spacetime.now(display.iana)
let abbrev = s.isDST() ? display.daylight.abbrev : display.standard.abbrev // (add some null-checks)
let time = `${s.time()} ${abbrev}`
// '4:20pm EDT'
work-in-progress.
MIT