* The locale matching algorithm to use.The default is "best fit". For information about this option, see the {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl#Locale_negotiation Intl page}.
*/
localeMatcher?:string;
/**
* The formatting style to use , the default is "decimal".
*/
style?:string;
numberingSystem?:string;
/**
* The unit to use in unit formatting, Possible values are core unit identifiers, defined in UTS #35, Part 2, Section 6. A subset of units from the full list was selected for use in ECMAScript. Pairs of simple units can be concatenated with "-per-" to make a compound unit. There is no default value; if the style is "unit", the unit property must be provided.
*/
unit?:string;
/**
* The unit formatting style to use in unit formatting, the defaults is "short".
*/
unitDisplay?:string;
/**
* The currency to use in currency formatting. Possible values are the ISO 4217 currency codes, such as "USD" for the US dollar, "EUR" for the euro, or "CNY" for the Chinese RMB — see the Current currency & funds code list. There is no default value; if the style is "currency", the currency property must be provided. It is only used when [[Style]] has the value "currency".
*/
currency?:string;
/**
* How to display the currency in currency formatting. It is only used when [[Style]] has the value "currency". The default is "symbol".
*
* "symbol" to use a localized currency symbol such as €,
*
* "code" to use the ISO currency code,
*
* "name" to use a localized currency name such as "dollar"
*/
currencyDisplay?:string;
/**
* Whether to use grouping separators, such as thousands separators or thousand/lakh/crore separators. The default is true.
*/
useGrouping?:boolean;
/**
* The minimum number of integer digits to use. Possible values are from 1 to 21; the default is 1.
* The minimum number of fraction digits to use. Possible values are from 0 to 20; the default for plain number and percent formatting is 0; the default for currency formatting is the number of minor unit digits provided by the {@link http://www.currency-iso.org/en/home/tables/table-a1.html ISO 4217 currency codes list} (2 if the list doesn't provide that information).
* The maximum number of fraction digits to use. Possible values are from 0 to 20; the default for plain number formatting is the larger of minimumFractionDigits and 3; the default for currency formatting is the larger of minimumFractionDigits and the number of minor unit digits provided by the {@link http://www.currency-iso.org/en/home/tables/table-a1.html ISO 4217 currency codes list} (2 if the list doesn't provide that information); the default for percent formatting is the larger of minimumFractionDigits and 0.
* @param locales - A string with a [BCP 47 language tag](http://tools.ietf.org/html/rfc5646), or an array of such strings.
* For the general form and interpretation of the locales argument,
* see the [`Intl` page](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl#Locale_identification_and_negotiation).
*
* @param options - An [object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/RelativeTimeFormat/RelativeTimeFormat#Parameters)
* with some or all of options of the formatting.
* An object with some or all of the following properties:
* - `localeMatcher` - The locale matching algorithm to use.
* Possible values are `"lookup"` and `"best fit"`; the default is `"best fit"`.
* For information about this option, see [Intl page](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Intl#Locale_negotiation).
* - `numeric` - The format of output message.
* Possible values are: `"always"` (default, e.g., `1 day ago`) or `"auto"` (e.g., `yesterday`).
* The `"auto"` value allows to not always have to use numeric values in the output.
* - `style` - The length of the internationalized message. Possible values are:
* `"long"` (default, e.g., in 1 month),
* `"short"` (e.g., in 1 mo.)
* or `"narrow"` (e.g., in 1 mo.). The narrow style could be similar to the short style for some locales.
* 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.
*
* @param locales - A string with a [BCP 47 language tag](http://tools.ietf.org/html/rfc5646), or an array of such strings.
* For the general form and interpretation of the locales argument,
* see the [`Intl` page](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl#Locale_identification_and_negotiation).
*
* @param options - An [object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/RelativeTimeFormat/RelativeTimeFormat#Parameters)
* with some or all of options of the formatting.
* An object with some or all of the following properties:
* - `localeMatcher` - The locale matching algorithm to use.
* Possible values are `"lookup"` and `"best fit"`; the default is `"best fit"`.
* For information about this option, see [Intl page](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Intl#Locale_negotiation).
* - `numeric` - The format of output message.
* Possible values are: `"always"` (default, e.g., `1 day ago`) or `"auto"` (e.g., `yesterday`).
* The `"auto"` value allows to not always have to use numeric values in the output.
* - `style` - The length of the internationalized message. Possible values are:
* `"long"` (default, e.g., in 1 month),
* `"short"` (e.g., in 1 mo.)
* or `"narrow"` (e.g., in 1 mo.). The narrow style could be similar to the short style for some locales.
*
* @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.
