Delni

const isVowel = (c: string) => 'aeiouy'.includes(c)
const yay = (word: string) => word + (isVowel(word[word.length - 1]) ? 'y' : '') + 'ay'
const isUpperString = (c: string) => c === c.toUpperCase()
const hasUpperCharacter = (word: string) => word.split('').find(isUpperString)

const restablishCase = (word: string) => hasUpperCharacter(word)
	? word[0].toUpperCase() + word.substring(1).toLowerCase()
	: word;

const toPigLatinWord = (word: string) => {

Delni

let x: number = 0

// Fonction pure: ne modifie pas x
function add(value: number) {
	return x + value
}

// Fonction impure: modifie x
function incrementBy(value: number) {
	x += value;