# Intl.PluralRules

The `Intl.PluralRules` object enables plural-sensitive formatting and plural language rules. It helps you determine which plural form (e.g., "one", "few", "many", "other") should be used for a given number in a specific locale.

## 1. Basic Usage

The constructor takes two optional arguments: `locales` and `options`. The `select()` method returns a string representing the plural category.

```javascript
const pr = new Intl.PluralRules('en-US');

console.log(pr.select(0));   // "other" (0 items)
console.log(pr.select(1));   // "one"   (1 item)
console.log(pr.select(2));   // "other" (2 items)
console.log(pr.select(100)); // "other" (100 items)
```

In English, most numbers are "other", except 1 which is "one".

## 2. Different Locales

Different languages have different pluralization rules.

```javascript
// Arabic (ar-EG) has specific rules for 0, 1, 2, 3-10, 11-99, etc.
const ar = new Intl.PluralRules('ar-EG');

console.log(ar.select(0));   // "zero"
console.log(ar.select(1));   // "one"
console.log(ar.select(2));   // "two"
console.log(ar.select(6));   // "few"
console.log(ar.select(18));  // "many"
console.log(ar.select(100)); // "other"
```

## 3. Plural Categories

The standard categories returned by `select()` are:
*   `zero`
*   `one`
*   `two`
*   `few`
*   `many`
*   `other`

Not all languages use all categories. English only uses `one` and `other`.

## 4. Cardinal vs. Ordinal

The `type` option determines whether you are looking for cardinal numbers (1, 2, 3 - quantity) or ordinal numbers (1st, 2nd, 3rd - ranking).

*   `cardinal`: (Default) "1 item", "2 items".
*   `ordinal`: "1st item", "2nd item".

```javascript
const prOrdinal = new Intl.PluralRules('en-US', { type: 'ordinal' });

console.log(prOrdinal.select(1)); // "one"   (st -> 1st)
console.log(prOrdinal.select(2)); // "two"   (nd -> 2nd)
console.log(prOrdinal.select(3)); // "few"   (rd -> 3rd)
console.log(prOrdinal.select(4)); // "other" (th -> 4th)
console.log(prOrdinal.select(21)); // "one"  (st -> 21st)
```

## 5. Practical Example: Mapping to Strings

You can use the result of `select()` to pick the correct string from a map or object.

[[programming/javascript/vanilla/javascript]]
[[programming/javascript/vanilla/intl-numberformat]]