Temporal.Instant.compare()

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The Temporal.Instant.compare() static method returns a number (-1, 0, or 1) indicating whether the first instant comes before, is the same as, or comes after the second instant. It is equivalent to comparing the epochNanoseconds of the two instants.

Syntax

Temporal.Instant.compare(instant1, instant2)

Parameters

instant1: A string or a Temporal.Instant instance representing the first instant to compare. It is converted to a Temporal.Instant object using the same algorithm as Temporal.Instant.from().
instant2: The second instant to compare, converted to a Temporal.Instant object using the same algorithm as instant1.

Return value

Returns -1 if instant1 comes before instant2, 0 if they are the same, and 1 if instant1 comes after.

Examples

Using Temporal.Instant.compare()

const instant1 = Temporal.Instant.from("2021-08-01T12:34:56Z");
const instant2 = Temporal.Instant.from("2021-08-01T12:34:56Z");

console.log(Temporal.Instant.compare(instant1, instant2)); // 0

const instant3 = Temporal.Instant.from("2021-08-01T13:34:56Z");
console.log(Temporal.Instant.compare(instant1, instant3)); // -1

Sorting an array of instants

The purpose of this compare() function is to act as a comparator to be passed to Array.prototype.sort() and related functions.

const instants = [
  Temporal.Instant.from("2021-08-01T12:34:56Z"),
  Temporal.Instant.from("2021-08-01T12:34:56+01:00"),
  Temporal.Instant.from("2021-08-01T12:34:56-01:00"),
];

instants.sort(Temporal.Instant.compare);
console.log(instants.map((instant) => instant.toString()));
// [ '2021-08-01T11:34:56Z', '2021-08-01T12:34:56Z', '2021-08-01T13:34:56Z' ]

Specifications

Specification
Temporal proposal # sec-temporal.instant.compare

Browser compatibility

	Desktop					Mobile						Server
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	Deno	Node.js
`compare`	No	No	No	No	No	No	No	No	No	No	No	1.40	No