array-group-by-to-map-ponyfill

Array.prototype.groupByToMap ponyfill.

A proposal to make grouping of items in an array easier.

Install

npm install array-group-by-to-map-ponyfill --save

Usage

import groupByToMap from 'array-group-by-to-map-ponyfill';

groupByToMap([1, 2, 3, 4, 5], (value) => (value % 2 === 0 ? 'even' : 'odd'));

// Map([['odd', [1, 3, 5]], ['even', [2, 4]]])

You can use named export preferNative if you wish to use native implementation if it’s available. In all other cases, ponyfill will be used. Beware of caveats!

API

groupByToMap(array, callback)

Returns: Map

Group array items to map.

array

Type: any[]

Array to group.

callback

Type: Function

Callback which should return key with which to group array.

| Argument | Type | Description | | -------- | -------- | ------------------------- | | value | any | Current iteration value. | | index | number | Current iteration index. | | array | any[] | Original array reference. |

Browser support

Tested in Chrome 72, Edge 15, Firefox 65 and should work in all modern browsers (support based on Browserslist configuration).

Test

Test suite is taken and modified from core-js test suite.

For automated tests, run npm run test:automated (append :watch for watcher support).

License

MIT © Ivan Nikolić