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Async.map() method

Map over promises concurrently

Signature:

static map<Element, NewElement>(iterable: AsyncIterable<MaybePromise<Element>> | Iterable<MaybePromise<Element>>, mapper: AsyncMapper<Element, NewElement>, options?: AsyncMapOptions): Promise<NewElement[]>;

Parameters

Parameter	Type	Description
iterable	AsyncIterable<MaybePromise<Element>> | Iterable<MaybePromise<Element>>
mapper	AsyncMapper<Element, NewElement>
options	AsyncMapOptions	(Optional)

Returns:

Promise<NewElement[]>

Remarks

This is different from Promise.all() in that you can control the concurrency and also decide whether or not to stop iterating when there’s an error.

Example

import { Async } from '@infiniteobjects/core-library';
import got from 'got';

const sites = [
	getWebsiteFromUsername('sindresorhus'), //=> Promise
	'https://avajs.dev',
	'https://github.com'
];

const mapper = async site => {
	const {requestUrl} = await got.head(site);
	return requestUrl;
};

const result = await Async.map(sites, mapper, { concurrency: 2 });

console.log(result);
//=> ['https://sindresorhus.com/', 'https://avajs.dev/', 'https://github.com/']