Passing values into generators through `.next()`

passing-values-to-generators.js

function* crossBridge() {
  const reply = yield 'What is your favorite color?';
  console.log(reply);
  if (reply !== 'yellow') return 'Wrong!'
  return 'You may pass.';
}

{
  const iter = crossBridge();
  const q = iter.next().value; // Iterator yields question
  console.log(q);
  const a = iter.next('blue').value; // Pass reply back into generator
  console.log(a);
}

// What is your favorite color?
// blue
// Wrong!


{
  const iter = crossBridge();
  const q = iter.next().value;
  console.log(q);
  const a = iter.next('yellow').value;
  console.log(a);
}

// What is your favorite color?
// yellow
// You may pass.