The Intl.PluralRules() constructor creates Intl.PluralRules objects.
Syntax
new Intl.PluralRules()
new Intl.PluralRules(locales)
new Intl.PluralRules(locales, options)
Note:
Intl.PluralRules()can only be constructed withnew. Attempting to call it withoutnewthrows a TypeError.
Parameters
locales- : A string with a BCP 47 language tag or an Intl.Locale instance, or an array of such locale identifiers. For the general form and interpretation of the
localesargument, see the parameter description on theIntlmain page.
- : A string with a BCP 47 language tag or an Intl.Locale instance, or an array of such locale identifiers. For the general form and interpretation of the
options: An object containing the following properties, in the order they are retrieved (all of them are optional):
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 Locale identification and negotiation.
- : The locale matching algorithm to use. Possible values are
type- : The type to use. Possible values are:
"cardinal"(default)- : For cardinal numbers (referring to the quantity of things).
"ordinal"- : For ordinal number (referring to the ordering or ranking of things, e.g. "1st", "2nd", "3rd" in English).
- : The type to use. Possible values are:
Intl.PluralRulesalso supports theIntl.NumberFormat()digit options (seeIntl.NumberFormat()for details):minimumIntegerDigitsminimumFractionDigitsmaximumFractionDigitsminimumSignificantDigitsmaximumSignificantDigitsroundingPriorityroundingIncrementroundingMode
These options are interpreted as if the
notationoption fromIntl.NumberFormatis"standard"andstyleis"decimal".
Exceptions
- RangeError
- : Thrown if
localesoroptionscontain invalid values.
- : Thrown if
Examples
Basic usage
In basic use without specifying a locale, a formatted string in the default locale and with default options is returned. This is useful to distinguish between singular and plural forms, e.g. "dog" and "dogs".
const pr = new Intl.PluralRules();
pr.select(0); // 'other' if in US English locale
pr.select(1); // 'one' if in US English locale
pr.select(2); // 'other' if in US English locale
Using options
The results can be customized using the options argument, which has one property called type which you can set to ordinal. This is useful to figure out the ordinal indicator, e.g. "1st", "2nd", "3rd", "4th", "42nd",
and so forth.
const pr = new Intl.PluralRules("en-US", { type: "ordinal" });
const suffixes = new Map([
["one", "st"],
["two", "nd"],
["few", "rd"],
["other", "th"],
]);
const formatOrdinals = (n) => {
const rule = pr.select(n);
const suffix = suffixes.get(rule);
return `${n}${suffix}`;
};
formatOrdinals(0); // '0th'
formatOrdinals(1); // '1st'
formatOrdinals(2); // '2nd'
formatOrdinals(3); // '3rd'
formatOrdinals(4); // '4th'
formatOrdinals(11); // '11th'
formatOrdinals(21); // '21st'
formatOrdinals(42); // '42nd'
formatOrdinals(103); // '103rd'