make-github-pseudonymous-again / set-alarm

:alarm_clock: Call a Function on a given Date

⏰ set-alarm

Call a Function on a given Date. The API tries to mimic the setTimeout API as best as possible. See docs.

import {
	setAlarm,
	clearAlarm,
	Alarm
} from 'set-alarm';

const firstOfApril2021AtNoonZuluTime = new Date('2021-04-01T12:00Z');

// Set an alarm
const alarm = setAlarm(() => {
	console.debug(new Date() - firstOfApril2021AtNoonZuluTime);
}, firstOfApril2021AtNoonZuluTime);

alarm instanceof Alarm; // true

// Two scenarios:
//  - if date is in the future: should trigger at or just after the date, logging a small nonnegative number
//  - if date is in the past: will trigger anyway logging a possibly large positive number
// It is up to you to ignore alarms for past dates (similar to `setTimeout(..., -2389324)`).

// OR Unenroll the callback (and the alarm will not trigger)
clearAlarm(alarm); // undefined