What does this log?

const word = "code";
const [first, second] = word;
console.log(first, second, [...word].length);

1. code code 4
2. c o 2
3. co de 2
4. c o 4

What does this log?

function isIterable(x) {
  return x != null && typeof x[Symbol.iterator] === "function";
}
console.log(isIterable([1]), isIterable({ a: 1 }), isIterable(new Map()), isIterable(null));

1. false false true false
2. true false true false
3. true false false false
4. true true true false

What does this log?

function* steps() {
  console.log("start");
  yield "A";
  console.log("end");
}
const g = steps();
console.log("created");
console.log(g.next().value);

1. start, created, A
2. created, A
3. created, start, A
4. start, A, end

What does this log?

function* abc() {
  yield "a";
  yield "b";
  return "c";
}
const g = abc();
g.next();
g.next();
console.log(g.next(), g.next());

1. {value: "c", done: false} {value: undefined, done: true}
2. {value: undefined, done: true} {value: undefined, done: true}
3. {value: "b", done: false} {value: "c", done: true}
4. {value: "c", done: true} {value: undefined, done: true}

What does this log?

function* nums() {
  let n = 1;
  while (true) {
    yield n++;
  }
}
const out = [];
for (const x of nums()) {
  if (x > 3) break;
  out.push(x);
}
console.log(out);

1. It never finishes
2. [1, 2, 3]
3. [1, 2, 3, 4]
4. []