メソッドチェーンっぽい書き方をしてみたかった

prototype.js

Number.prototype.fizz = function fizz () {
  if (this % 3 == 0) {
    return "Fizz"
  } else {
    return this
  }
}

Number.prototype.buzz = function buzz () {
  if (this % 5 == 0) {
    return "Buzz"
  } else {
    return this
  }
}

Number.prototype.fizzbuzz = function fizzbuzz () {
  if (this % 15 == 0) {
    return "FizzBuzz"
  } else {
    return this
  }
}

Number.prototype.identity = function identity () {return this}

String.prototype.fizz = function fizz () {return this}
String.prototype.buzz = function buzz () {return this}
String.prototype.identity = function identity () {return this}


const output = [...Array(30).keys()].map(x=>x+1).map(x=>x.fizzbuzz().fizz().buzz().identity())

console.log(output)