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YCM Jason
YCM Jason

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My attempt on asyncToGenerator()

Not gonna explain so much, just sharing my recent attempt on implementing asyncToGenerator(). Please do tell me what you think. πŸ˜€

function asyncToGenerator(fn) {
  const ensurePromise = v => Promise.resolve(v);

  const stepContext = (context, nextOrThrow, prev) => {
    const { value, done } = context[nextOrThrow](prev);

    if (done) return ensurePromise(value);

    return ensurePromise(value)
      .then(v => stepContext(context, 'next', v))
      .catch(err => stepContext(context, 'throw', err));
  };

  return function(...args) {
    const context = fn.apply(this, args); 
    return stepContext(context, 'next');
  };
}
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To use:

asyncToGenerator(function* () {
  const res = yield axios.get('https://www.ycmjason.com');
  console.log(res);
})();
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Top comments (2)

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mrm8488 profile image
Manuel Romero

I created a module to do something similar: github.com/mrm8488/asyncflow

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ycmjason profile image
YCM Jason

Nice work!

It's just a proof of concept I guess. We all use async/await nowadays! But it's really fun to try to write this from scratch.