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docs: remove outdated parts about Promise.allSettled #3845

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24 changes: 0 additions & 24 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 @@ -171,28 +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

Expand Down