Temporal.PlainYearMonth.prototype.eraYear

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 eraYear accessor property of Temporal.PlainYearMonth instances returns a non-negative integer representing the year of this year-month within the era, or undefined if the calendar does not use eras (e.g. ISO 8601). The year index usually starts from 1 (more common) or 0, and years in an era can decrease with time (e.g. Gregorian BCE). era and eraYear together uniquely identify a year in a calendar, in the same way that year does. It is calendar-dependent.

The set accessor of eraYear is undefined. You cannot change this property directly. Use the with() method to create a new Temporal.PlainYearMonth object with the desired new value.

For general information and more examples, see Temporal.PlainDate.prototype.eraYear.

Examples

Using eraYear

js
const ym = Temporal.PlainYearMonth.from("2021-07"); // ISO 8601 calendar
console.log(ym.eraYear); // undefined

const ym2 = Temporal.PlainYearMonth.from("2021-07-01[u-ca=gregory]");
console.log(ym2.eraYear); // 2021

const ym3 = Temporal.PlainYearMonth.from("-002021-07-01[u-ca=gregory]");
console.log(ym3.eraYear); // 2022; 0000 is used for the year 1 BC

const ym4 = Temporal.PlainYearMonth.from("2021-07-01[u-ca=japanese]");
console.log(ym4.eraYear); // 3

Specifications

Specification
Temporal proposal
# sec-get-temporal.plainyearmonth.prototype.erayear

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
eraYear
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