The Intl.DateTimeFormat.prototype.format property returns a getter function that formats a date according to the locale and formatting options of this Intl.DateTimeFormat object.
The Intl.DateTimeFormat.prototype.resolvedOptions() method returns a new object with properties reflecting the locale and date and time formatting options computed during initialization of this DateTimeFormat object.
The Intl.DateTimeFormat.supportedLocalesOf() method returns an array containing those of the provided locales that are supported in date and time formatting without having to fall back to the runtime's default locale.