declare namespace pMap { | |
interface Options { | |
/** | |
Number of concurrently pending promises returned by `mapper`. | |
Must be an integer from 1 and up or `Infinity`. | |
@default Infinity | |
*/ | |
readonly concurrency?: number; | |
/** | |
When set to `false`, instead of stopping when a promise rejects, it will wait for all the promises to settle and then reject with an [aggregated error](https://github.com/sindresorhus/aggregate-error) containing all the errors from the rejected promises. | |
@default true | |
*/ | |
readonly stopOnError?: boolean; | |
} | |
/** | |
Function which is called for every item in `input`. Expected to return a `Promise` or value. | |
@param element - Iterated element. | |
@param index - Index of the element in the source array. | |
*/ | |
type Mapper<Element = any, NewElement = unknown> = ( | |
element: Element, | |
index: number | |
) => NewElement | Promise<NewElement>; | |
} | |
/** | |
@param input - Iterated over concurrently in the `mapper` function. | |
@param mapper - Function which is called for every item in `input`. Expected to return a `Promise` or value. | |
@returns A `Promise` that is fulfilled when all promises in `input` and ones returned from `mapper` are fulfilled, or rejects if any of the promises reject. The fulfilled value is an `Array` of the fulfilled values returned from `mapper` in `input` order. | |
@example | |
``` | |
import pMap = require('p-map'); | |
import got = require('got'); | |
const sites = [ | |
getWebsiteFromUsername('https://sindresorhus'), //=> Promise | |
'https://ava.li', | |
'https://github.com' | |
]; | |
(async () => { | |
const mapper = async site => { | |
const {requestUrl} = await got.head(site); | |
return requestUrl; | |
}; | |
const result = await pMap(sites, mapper, {concurrency: 2}); | |
console.log(result); | |
//=> ['https://sindresorhus.com/', 'https://ava.li/', 'https://github.com/'] | |
})(); | |
``` | |
*/ | |
declare function pMap<Element, NewElement>( | |
input: Iterable<Element>, | |
mapper: pMap.Mapper<Element, NewElement>, | |
options?: pMap.Options | |
): Promise<NewElement[]>; | |
export = pMap; | |