Use JSDoc

Overview

The @readonly tag indicates that a symbol is intended to be read-only. Note this is for the purpose of documentation only - JSDoc won't check whether you've actually treated the symbol as read-only in your code.

Examples

Using the @readonly tag

/**
 * A constant.
 * @readonly
 * @const {number}
 */
const FOO = 1;

Using the @readonly tag with a getter

/**
 * Options for ordering a delicious slice of pie.
 * @namespace
 */
var pieOptions = {
	/**
	 * Plain.
	 */
	plain: 'pie',
	/**
	 * A la mode.
	 * @readonly
	 */
	get aLaMode() {
		return this.plain + ' with ice cream';
	}
};