Number.prototype[Symbol.iterator] = function* () {
  if (isNaN(this) || !isFinite(this)) {
    throw new ReferenceError('Non-iterable number')
  }

  const abs = Math.abs(this)
  const isNegative = this < 0
  
  for (let i = 0; i < abs; i++) {
    yield isNegative ? -i : i
  }
}

[...10] // [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
for (let i of 5) {
  // ...
}