Pluralize string
Returns the singular or plural form of the word based on the input number, using an optional dictionary if supplied.
- Use a closure to define a function that pluralizes the given
word
based on the value ofnum
. - If
num
is either-1
or1
, return the singular form of the word. - If
num
is any other number, return theplural
form. - Omit the third argument,
plural
, to use the default of the singular word +s
, or supply a custom pluralizedword
when necessary. - If the first argument is an
object
, return a function which can use the supplied dictionary to resolve the correct plural form of the word.
const pluralize = (val, word, plural = word + 's') => { const _pluralize = (num, word, plural = word + 's') => [1, -1].includes(Number(num)) ? word : plural; if (typeof val === 'object') return (num, word) => _pluralize(num, word, val[word]); return _pluralize(val, word, plural); }; pluralize(0, 'apple'); // 'apples' pluralize(1, 'apple'); // 'apple' pluralize(2, 'apple'); // 'apples' pluralize(2, 'person', 'people'); // 'people' const PLURALS = { person: 'people', radius: 'radii' }; const autoPluralize = pluralize(PLURALS); autoPluralize(2, 'person'); // 'people'