Categories
JavaScript Answers

How to filter an array with a function that returns a promise with JavaScript?

Spread the love

Sometimes, we want to filter an array with a function that returns a promise with JavaScript.

In this article, we’ll look at how to filter an array with a function that returns a promise with JavaScript.

How to filtering an array with a function that returns a promise with JavaScript?

To filter an array with a function that returns a promise with JavaScript, we can use the Promise.all method with the array filter method.

For instance, we write

const filterPromise = async (values, fn) => {
  const booleans = await Promise.all(values.map(fn));
  const filtered = values.filter((_, i) => booleans[i]);
  return filtered;
};

to define the filterPromise function.

In it, we call Promise.all with an array of promises we get from values.map(fn).

Then we call values.filter with a callback that returns an array of filtered values according to the values of booleans[i].

Conclusion

To filter an array with a function that returns a promise with JavaScript, we can use the Promise.all method with the array filter method.

Leave a Reply

Your email address will not be published.

If you like the content of this blog, subscribe to my email list to get exclusive articles not available to anyone else.