Javascript prime number generator function

primes.mjs

function * primes(max = 1_000) {
  const isComposite = []
  for (let i = 2; i <= max; i++) if (!isComposite[i]) {
    yield i
    for (let j = i**2; j <= max; j += i)
      isComposite[j] = true
  }
}