Temporal.PlainYearMonth.prototype.subtract()

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 subtract() method of Temporal.PlainYearMonth instances returns a new Temporal.PlainYearMonth object representing this year-month moved backward by a given duration (in a form convertible by Temporal.Duration.from()).

If you want to subtract two year-months and get a duration, use since() or until() instead.

Syntax

js
subtract(duration)
subtract(duration, options)

Parameters

duration

A string, an object, or a Temporal.Duration instance representing a duration to subtract from this year-month. It is converted to a Temporal.Duration object using the same algorithm as Temporal.Duration.from().

options Optional

An object containing the following property:

overflow Optional

A string specifying the behavior when a date component is out of range. Possible values are:

"constrain" (default)

The date component is clamped to the valid range.

"reject"

A RangeError is thrown if the date component is out of range.

Return value

A new Temporal.PlainYearMonth object representing the year-month specified by the original PlainYearMonth, minus the duration.

Description

Subtracting a duration is equivalent to adding its negation, so all the same considerations apply. Subtracting a positive duration starts from the end of the year-month and moves backward, so any increment smaller than the month's length is ignored.

Examples

Subtracting a duration

js
const start = Temporal.PlainYearMonth.from("2022-01");
const end = start.subtract({ years: 1, months: 2, weeks: 3, days: 4 });
console.log(end.toString()); // 2020-11

For more examples, see add().

Specifications

Specification
Temporal proposal
# sec-temporal.plainyearmonth.prototype.subtract

Browser compatibility

BCD tables only load in the browser

See also