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Remove "recently added" marking for some Promise static methods #3790

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Remove "recently added" marking for some Promise static methods #3790

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29 changes: 2 additions & 27 deletions 1-js/11-async/05-promise-api/article.md
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Expand Up @@ -119,8 +119,6 @@ So we are able to pass ready values to `Promise.all` where convenient.

## Promise.allSettled

[recent browser="new"]

`Promise.all` rejects as a whole if any promise rejects. That's good for "all or nothing" cases, when we need *all* results successful to proceed:

```js
Expand Down Expand Up @@ -171,29 +169,6 @@ The `results` in the line `(*)` above will be:

So for each promise we get its status and `value/error`.

### Polyfill

If the browser doesn't support `Promise.allSettled`, it's easy to polyfill:

```js
if (!Promise.allSettled) {
const rejectHandler = reason => ({ status: 'rejected', reason });

const resolveHandler = value => ({ status: 'fulfilled', value });

Promise.allSettled = function (promises) {
const convertedPromises = promises.map(p => Promise.resolve(p).then(resolveHandler, rejectHandler));
return Promise.all(convertedPromises);
};
}
```

In this code, `promises.map` takes input values, turns them into promises (just in case a non-promise was passed) with `p => Promise.resolve(p)`, and then adds `.then` handler to every one.

That handler turns a successful result `value` into `{status:'fulfilled', value}`, and an error `reason` into `{status:'rejected', reason}`. That's exactly the format of `Promise.allSettled`.

Now we can use `Promise.allSettled` to get the results of *all* given promises, even if some of them reject.

## Promise.race

Similar to `Promise.all`, but waits only for the first settled promise and gets its result (or error).
Expand Down Expand Up @@ -312,11 +287,11 @@ In practice, this method is almost never used.
There are 6 static methods of `Promise` class:

1. `Promise.all(promises)` -- waits for all promises to resolve and returns an array of their results. If any of the given promises rejects, it becomes the error of `Promise.all`, and all other results are ignored.
2. `Promise.allSettled(promises)` (recently added method) -- waits for all promises to settle and returns their results as an array of objects with:
2. `Promise.allSettled(promises)` -- waits for all promises to settle and returns their results as an array of objects with:
- `status`: `"fulfilled"` or `"rejected"`
- `value` (if fulfilled) or `reason` (if rejected).
3. `Promise.race(promises)` -- waits for the first promise to settle, and its result/error becomes the outcome.
4. `Promise.any(promises)` (recently added method) -- waits for the first promise to fulfill, and its result becomes the outcome. If all of the given promises are rejected, [`AggregateError`](mdn:js/AggregateError) becomes the error of `Promise.any`.
4. `Promise.any(promises)` -- waits for the first promise to fulfill, and its result becomes the outcome. If all of the given promises are rejected, [`AggregateError`](mdn:js/AggregateError) becomes the error of `Promise.any`.
5. `Promise.resolve(value)` -- makes a resolved promise with the given value.
6. `Promise.reject(error)` -- makes a rejected promise with the given error.

Expand Down