Promise.any

I think Promise.any() must be in this article.
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Mustafa Kemal Tuna 2020-11-17 07:55:57 +03:00 committed by GitHub
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@ -217,6 +217,29 @@ Promise.race([
The first promise here was fastest, so it became the result. After the first settled promise "wins the race", all further results/errors are ignored. The first promise here was fastest, so it became the result. After the first settled promise "wins the race", all further results/errors are ignored.
## Promise.any
Similar to `Promise.race`, but waits only for the first fulfilled promise and gets its result. If all of the given promises are rejected, then the returned promise is rejected.
The syntax is:
```js
let promise = Promise.any(iterable);
```
For instance, here the result will be `1`:
```js run
Promise.race([
new Promise((resolve, reject) => setTimeout(() => reject(new Error("Whoops!")), 1000)),
new Promise((resolve, reject) => setTimeout(() => resolve(1), 2000)),
new Promise((resolve, reject) => setTimeout(() => resolve(3), 3000))
]).then(alert); // 1
```
The first promise here was fastest, but it rejecets, so the second promise became the result. After the first fulfilled promise "wins the race", all further results are ignored.
## Promise.resolve/reject ## Promise.resolve/reject
Methods `Promise.resolve` and `Promise.reject` are rarely needed in modern code, because `async/await` syntax (we'll cover it [a bit later](info:async-await)) makes them somewhat obsolete. Methods `Promise.resolve` and `Promise.reject` are rarely needed in modern code, because `async/await` syntax (we'll cover it [a bit later](info:async-await)) makes them somewhat obsolete.