What Is The Difference Between Promise Any And Promise Race

When working with asynchronous code in JavaScript, you may have come across Promise.any and Promise.race methods. These two methods offer unique ways to handle multiple promises, but understanding the differences between them can be crucial for efficient programming. Let's delve into the distinctions between Promise.any and Promise.race to help you make the right choice for your projects.

**Promise.any**

Promise.any is a relatively new addition to the Promise API, introduced in ECMAScript 2021, which allows you to wait for the first promise out of an array of promises to be fulfilled or rejected. It returns a single settled promise, either fulfilled with the value of the first resolved promise or rejected with an array of rejection reasons if all promises are rejected.

When you need to work with a collection of promises and only care about the first one that resolves or rejects, Promise.any comes in handy. It provides a clean and concise way to handle such scenarios without manually tracking the status of each promise.

Here's a basic example of how Promise.any works:

Javascript

const promises = [
  somePromiseFunction(),
  anotherPromiseFunction(),
  oneMorePromiseFunction(),
];

Promise.any(promises)
  .then((value) =&gt; {
    console.log('First fulfilled promise value:', value);
  })
  .catch((error) =&gt; {
    console.error('All promises were rejected:', error);
  });

**Promise.race**

On the other hand, Promise.race has been around since ECMAScript 2015 (ES6) and functions differently from Promise.any. With Promise.race, you can supply an array of promises and get back a single promise that settles as soon as any of the promises in the array settles, be it fulfilled or rejected.

This can be useful in scenarios where you want to race multiple asynchronous operations and take the result of the one that completes first. It's essential to note that unlike Promise.any, Promise.race does not aggregate the results of all promises; it only resolves with the value or rejection reason of the first settled promise.

Here's a simple illustration of Promise.race in action:

Javascript

const promises = [
  promiseA(),
  promiseB(),
  promiseC(),
];

Promise.race(promises)
  .then((value) =&gt; {
    console.log('First settled promise value:', value);
  })
  .catch((error) =&gt; {
    console.error('First settled promise error:', error);
  });

By understanding the distinctions between Promise.any and Promise.race, you can effectively leverage these methods to handle asynchronous tasks in your JavaScript projects. Whether you need to await the first fulfilled promise or race multiple promises to get the fastest result, choosing the right method can streamline your code and make it more efficient.

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