Functional / Declarative FizzBuzz

functional-fizzbuzz.js

const isFizz = number => number % 5 === 0
const isBuzz = number => number % 3 === 0

const newArrayInRange = (min, max) => [...Array(max + 1).keys()].slice(min)

const fizzBuzz = (min, max) => newArrayInRange(min, max)
  .map(number => {
    if (isFizz(number) && isBuzz(number)) {
      return 'fizzbuzz'
    }
    if (isFizz(number)) {
      return 'fizz'
    }
    if (isBuzz(number)) {
      return 'buzz'
    }
    return number
  })
  .join('\n')

console.log(fizzBuzz(1, 100))