Javascript pluralize a string

Question

In PHP, I use Kuwamoto's class to pluralize nouns in my strings. I didn't find something as good as this script in javascript except for some plugins. So, it would be great to have a javascript function based on Kuwamoto's class.

http://kuwamoto.org/2007/12/17/improved-pluralizing-in-php-actionscript-and-ror/

Answer 1

I’ve created a very simple library that can be used for words pluralization in JavaScript. It transparently uses CLDR database for multiple locales, so it supports almost any language you would like to use. It’s API is very minimalistic and integration is extremely simple. It’s called Numerous.

I’ve also written a small introduction article to it: «How to pluralize any word in different languages using JavaScript?».

Feel free to use it in your project. I will also be glad for your feedback on it.

Answer 2

function pluralize( /* n, [ n2, n3, ... ] str */ ) {
    var n = Array.prototype.slice.call( arguments ) ;
    var str = n.pop(), iMax = n.length - 1, i = -1, j ;
    str = str.replace( /\$\$|\$(\d+)/g,
        function( m, p1 ) { return m == '$$' ? '$' : n[+p1-1] }
    ) ;
    return str.replace( /[(](.*?)([+-])(\d*)(?:,([^,)]*))?(?:,([^)]*))?[)]/g,
        function( match, one, sign, abs, not1, zero ) {
            // if abs, use indicated element in the array of numbers
            // instead of using the next element in sequence
            abs ? ( j = +abs - 1 ) : ( i < iMax && i++, j = i ) ;
            if ( zero != undefined && n[j] == 0 ) return zero ;
            return ( n[j] != 1 ) == ( sign == '+' ) ? ( not1 || 's' ) : one ;
        }
    ) ;  
}

console.log( pluralize( 1, 'the cat(+) live(-) outside' ) ) ;
// the cat lives outside
console.log( pluralize( 2, 'the child(+,ren) (is+,are) inside' ) ) ;
// the children are inside
console.log( pluralize( 0, '$1 dog(+), ($1+,$1,no) dog(+), ($1+,$1,no) dog(+,,)' ) ) ;
// 0 dogs, no dogs, no dog
console.log( pluralize( 100, 1, '$1 penn(y+,ies) make(-1) $$$2' ) ) ;
// 100 pennies make $1
console.log( pluralize( 1, 0.01, '$1 penn(y+,ies) make(-1) $$$2' ) ) ;
// 1 penny makes $0.01

Answer 3

Using @sarink's answer, I made a function to create a string using key value pairs data and pluralizing the keys. Here's the snippet:

// Function to create a string from given key value pairs and pluralize keys
const stringPluralize = function(data){
    var suffix = 's';
    var str = '';
    $.each(data, function(key, val){
        if(str != ''){
            str += val>0 ? ` and ${val} ${key}${val !== 1 ? suffix : ''}` : '';
        }
        else{
            str = val>0 ? `${val} ${key}${val !== 1 ? suffix : ''}` : '';
        }
    });
    return str;
}
var leftDays = '1';
var leftHours = '12';
var str = stringPluralize({day:leftDays, hour:leftHours});
console.log(str) // Gives 1 day and 12 hours

Answer 4

Simple version (ES6):

const maybePluralize = (count, noun, suffix = 's') =>
  `${count} ${noun}${count !== 1 ? suffix : ''}`;

Usage:

maybePluralize(0, 'turtle'); // 0 turtles
maybePluralize(1, 'turtle'); // 1 turtle
maybePluralize(2, 'turtle'); // 2 turtles
maybePluralize(3, 'fox', 'es'); // 3 foxes

This obviously doesn't support all english edge-cases, but it's suitable for most purposes

Answer 5

The new intl API spec from ECMA will provide the plural rules function, https://github.com/tc39/proposal-intl-plural-rules

Here's the polyfill that can be used today https://github.com/eemeli/IntlPluralRules

Answer 6

Based on @pmrotule answer with some typescript magic and some additions to the uncountable array. I add here the plural and singular functions.

The plural version:

/**
 * Returns the plural of an English word.
 *
 * @export
 * @param {string} word
 * @param {number} [amount]
 * @returns {string}
 */
export function plural(word: string, amount?: number): string {
    if (amount !== undefined && amount === 1) {
        return word
    }
    const plural: { [key: string]: string } = {
        '(quiz)$'               : "$1zes",
        '^(ox)$'                : "$1en",
        '([m|l])ouse$'          : "$1ice",
        '(matr|vert|ind)ix|ex$' : "$1ices",
        '(x|ch|ss|sh)$'         : "$1es",
        '([^aeiouy]|qu)y$'      : "$1ies",
        '(hive)$'               : "$1s",
        '(?:([^f])fe|([lr])f)$' : "$1$2ves",
        '(shea|lea|loa|thie)f$' : "$1ves",
        'sis$'                  : "ses",
        '([ti])um$'             : "$1a",
        '(tomat|potat|ech|her|vet)o$': "$1oes",
        '(bu)s$'                : "$1ses",
        '(alias)$'              : "$1es",
        '(octop)us$'            : "$1i",
        '(ax|test)is$'          : "$1es",
        '(us)$'                 : "$1es",
        '([^s]+)$'              : "$1s"
    }
    const irregular: { [key: string]: string } = {
        'move'   : 'moves',
        'foot'   : 'feet',
        'goose'  : 'geese',
        'sex'    : 'sexes',
        'child'  : 'children',
        'man'    : 'men',
        'tooth'  : 'teeth',
        'person' : 'people'
    }
    const uncountable: string[] = [
        'sheep',
        'fish',
        'deer',
        'moose',
        'series',
        'species',
        'money',
        'rice',
        'information',
        'equipment',
        'bison',
        'cod',
        'offspring',
        'pike',
        'salmon',
        'shrimp',
        'swine',
        'trout',
        'aircraft',
        'hovercraft',
        'spacecraft',
        'sugar',
        'tuna',
        'you',
        'wood'
    ]
    // save some time in the case that singular and plural are the same
    if (uncountable.indexOf(word.toLowerCase()) >= 0) {
        return word
    }
    // check for irregular forms
    for (const w in irregular) {
        const pattern = new RegExp(`${w}$`, 'i')
        const replace = irregular[w]
        if (pattern.test(word)) {
            return word.replace(pattern, replace)
        }
    }
    // check for matches using regular expressions
    for (const reg in plural) {
        const pattern = new RegExp(reg, 'i')
        if (pattern.test(word)) {
            return word.replace(pattern, plural[reg])
        }
    }
    return word
}

And the singular version:

/**
 * Returns the singular of an English word.
 *
 * @export
 * @param {string} word
 * @param {number} [amount]
 * @returns {string}
 */
export function singular(word: string, amount?: number): string {
    if (amount !== undefined && amount !== 1) {
        return word
    }
    const singular: { [key: string]: string } = {
        '(quiz)zes$'             : "$1",
        '(matr)ices$'            : "$1ix",
        '(vert|ind)ices$'        : "$1ex",
        '^(ox)en$'               : "$1",
        '(alias)es$'             : "$1",
        '(octop|vir)i$'          : "$1us",
        '(cris|ax|test)es$'      : "$1is",
        '(shoe)s$'               : "$1",
        '(o)es$'                 : "$1",
        '(bus)es$'               : "$1",
        '([m|l])ice$'            : "$1ouse",
        '(x|ch|ss|sh)es$'        : "$1",
        '(m)ovies$'              : "$1ovie",
        '(s)eries$'              : "$1eries",
        '([^aeiouy]|qu)ies$'     : "$1y",
        '([lr])ves$'             : "$1f",
        '(tive)s$'               : "$1",
        '(hive)s$'               : "$1",
        '(li|wi|kni)ves$'        : "$1fe",
        '(shea|loa|lea|thie)ves$': "$1f",
        '(^analy)ses$'           : "$1sis",
        '((a)naly|(b)a|(d)iagno|(p)arenthe|(p)rogno|(s)ynop|(t)he)ses$': "$1$2sis",
        '([ti])a$'               : "$1um",
        '(n)ews$'                : "$1ews",
        '(h|bl)ouses$'           : "$1ouse",
        '(corpse)s$'             : "$1",
        '(us)es$'                : "$1",
        's$'                     : ""
    }
    const irregular: { [key: string]: string } = {
        'move'   : 'moves',
        'foot'   : 'feet',
        'goose'  : 'geese',
        'sex'    : 'sexes',
        'child'  : 'children',
        'man'    : 'men',
        'tooth'  : 'teeth',
        'person' : 'people'
    }
    const uncountable: string[] = [
        'sheep',
        'fish',
        'deer',
        'moose',
        'series',
        'species',
        'money',
        'rice',
        'information',
        'equipment',
        'bison',
        'cod',
        'offspring',
        'pike',
        'salmon',
        'shrimp',
        'swine',
        'trout',
        'aircraft',
        'hovercraft',
        'spacecraft',
        'sugar',
        'tuna',
        'you',
        'wood'
    ]
    // save some time in the case that singular and plural are the same
    if (uncountable.indexOf(word.toLowerCase()) >= 0) {
        return word
    }
    // check for irregular forms
    for (const w in irregular) {
        const pattern = new RegExp(`${irregular[w]}$`, 'i')
        const replace = w
        if (pattern.test(word)) {
            return word.replace(pattern, replace)
        }
    }
    // check for matches using regular expressions
    for (const reg in singular) {
        const pattern = new RegExp(reg, 'i')
        if (pattern.test(word)) {
            return word.replace(pattern, singular[reg])
        }
    }
    return word
}