How to get the nth value of a JavaScript generator?

Question

How can I get the nth value of a generator?

function *index() {
  let x = 0;
  while(true)
    yield x++;
}

// the 1st value
let a = index();
console.log(a.         


        

Answer 1

A simple loop will do:

let n = 10,
    iter = index();
while (--n > 0) iter.next();
console.log(iter.next().value); // 9