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

js
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()

js
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.

js
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

Report problems with this compatibility data on GitHub
desktopmobileserver
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Deno
Node.js
compare
Experimental

Legend

Tip: you can click/tap on a cell for more information.

No support
No support
Experimental. Expect behavior to change in the future.
See implementation notes.
User must explicitly enable this feature.

See also