83 lines
3.1 KiB
Plaintext
83 lines
3.1 KiB
Plaintext
|
# array.prototype.flatmap <sup>[![Version Badge][npm-version-svg]][package-url]</sup>
|
||
|
|
||
|
[![github actions][actions-image]][actions-url]
|
||
|
[![coverage][codecov-image]][codecov-url]
|
||
|
[![dependency status][deps-svg]][deps-url]
|
||
|
[![dev dependency status][dev-deps-svg]][dev-deps-url]
|
||
|
[![License][license-image]][license-url]
|
||
|
[![Downloads][downloads-image]][downloads-url]
|
||
|
|
||
|
[![npm badge][npm-badge-png]][package-url]
|
||
|
|
||
|
An ES2019 spec-compliant `Array.prototype.flatMap` shim/polyfill/replacement that works as far down as ES3.
|
||
|
|
||
|
This package implements the [es-shim API](https://github.com/es-shims/api) interface. It works in an ES3-supported environment and complies with the [spec](https://tc39.es/ecma262/#sec-array.prototype.flatmap).
|
||
|
|
||
|
Because `Array.prototype.flatMap` depends on a receiver (the `this` value), the main export takes the array to operate on as the first argument.
|
||
|
|
||
|
## Getting started
|
||
|
|
||
|
```sh
|
||
|
npm install --save array.prototype.flatmap
|
||
|
```
|
||
|
|
||
|
## Usage/Examples
|
||
|
|
||
|
```js
|
||
|
var flatMap = require('array.prototype.flatmap');
|
||
|
var assert = require('assert');
|
||
|
|
||
|
var arr = [1, [2], [], 3];
|
||
|
|
||
|
var results = flatMap(arr, function (x, i) {
|
||
|
assert.equal(x, arr[i]);
|
||
|
return x;
|
||
|
});
|
||
|
|
||
|
assert.deepEqual(results, [1, 2, 3]);
|
||
|
```
|
||
|
|
||
|
```js
|
||
|
var flatMap = require('array.prototype.flatmap');
|
||
|
var assert = require('assert');
|
||
|
/* when Array#flatMap is not present */
|
||
|
delete Array.prototype.flatMap;
|
||
|
var shimmedFlatMap = flatMap.shim();
|
||
|
|
||
|
var mapper = function (x) { return [x, 1]; };
|
||
|
|
||
|
assert.equal(shimmedFlatMap, flatMap.getPolyfill());
|
||
|
assert.deepEqual(arr.flatMap(mapper), flatMap(arr, mapper));
|
||
|
```
|
||
|
|
||
|
```js
|
||
|
var flatMap = require('array.prototype.flatmap');
|
||
|
var assert = require('assert');
|
||
|
/* when Array#flatMap is present */
|
||
|
var shimmedIncludes = flatMap.shim();
|
||
|
|
||
|
var mapper = function (x) { return [x, 1]; };
|
||
|
|
||
|
assert.equal(shimmedIncludes, Array.prototype.flatMap);
|
||
|
assert.deepEqual(arr.flatMap(mapper), flatMap(arr, mapper));
|
||
|
```
|
||
|
|
||
|
## Tests
|
||
|
Simply clone the repo, `npm install`, and run `npm test`
|
||
|
|
||
|
[package-url]: https://npmjs.org/package/array.prototype.flatmap
|
||
|
[npm-version-svg]: https://versionbadg.es/es-shims/Array.prototype.flatMap.svg
|
||
|
[deps-svg]: https://david-dm.org/es-shims/Array.prototype.flatMap.svg
|
||
|
[deps-url]: https://david-dm.org/es-shims/Array.prototype.flatMap
|
||
|
[dev-deps-svg]: https://david-dm.org/es-shims/Array.prototype.flatMap/dev-status.svg
|
||
|
[dev-deps-url]: https://david-dm.org/es-shims/Array.prototype.flatMap#info=devDependencies
|
||
|
[npm-badge-png]: https://nodei.co/npm/array.prototype.flatmap.png?downloads=true&stars=true
|
||
|
[license-image]: https://img.shields.io/npm/l/array.prototype.flatmap.svg
|
||
|
[license-url]: LICENSE
|
||
|
[downloads-image]: https://img.shields.io/npm/dm/array.prototype.flatmap.svg
|
||
|
[downloads-url]: https://npm-stat.com/charts.html?package=array.prototype.flatmap
|
||
|
[codecov-image]: https://codecov.io/gh/es-shims/Array.prototype.flatMap/branch/main/graphs/badge.svg
|
||
|
[codecov-url]: https://app.codecov.io/gh/es-shims/Array.prototype.flatMap/
|
||
|
[actions-image]: https://img.shields.io/endpoint?url=https://github-actions-badge-u3jn4tfpocch.runkit.sh/es-shims/Array.prototype.flatMap
|
||
|
[actions-url]: https://github.com/es-shims/Array.prototype.flatMap/actions
|