Loop Problem

1-problem.ts

let count = 0;
async function* loop() {
  while (true) {
    await new Promise(resolve => setTimeout(resolve, 3000));
    yield count++;
  }
}
(async () => {
  for await (const n of loop()) {
    console.log(n);
  }
})();

2-answer.ts

let count = 0;
async function* loop() {
  while (true) {
    yield count++;
  }
}
function start(f) {
  let timeout = null;
  let abort = false;
  (async () => {
    for await (const n of loop()) {
      await new Promise(resolve => {
        timeout = setTimeout(resolve, 3000);
      });
      if (abort) {
        break;
      }
      await f(n);
    }
  })();
  return () => {
    timeout && clearTimeout(timeout);
    abort = true;
  };
}
const end = start(async n => {
  console.log(n);
});