AsyncIterator doodling

asyncIterator-doodling.js

const sleep = ms => new Promise(r => setTimeout(r, ms));

const numbersFromGenerator = fromI => {
  let i = fromI;
  return {
    [Symbol.asyncIterator]: async function*() {
      while (true) {
        await sleep(500);
        yield i++;
      }
    }
  };
};

const printNumbersUntil = async fn => {
  for await (const i of numbersFromGenerator(1)) {
    console.log(`Next number is: ${i}`);
    if (fn(i)) {
      break;
    }
  }
};
printNumbersUntil(x => x >= 10);