An ES7/ES2016 spec-compliant Array.prototype.includes shim/polyfill/replacement that works as far down as ES3.
This package implements the es-shim API interface. It works in an ES3-supported environment and complies with the proposed spec.
Because Array.prototype.includes depends on a receiver (the this value), the main export takes the array to operate on as the first argument.
Engines that need this package include: - IE (all versions) - Safari < 9 - Firefox < 43, and 99-101 - Chrome < 47 - Edge < 14 - node < 6
sh
npm install --save array-includes
Basic usage: includes(array, value[, fromIndex=0])
```js var includes = require('array-includes'); var assert = require('assert'); var arr = [ 'one', 'two' ];
includes(arr, 'one'); // true includes(arr, 'three'); // false includes(arr, 'one', 1); // false ```
```js var arr = [ 1, 'foo', NaN, -0 ];
assert.equal(arr.indexOf(0) > -1, true); assert.equal(arr.indexOf(-0) > -1, true); assert.equal(includes(arr, 0), true); assert.equal(includes(arr, -0), true);
assert.equal(arr.indexOf(NaN) > -1, false); assert.equal(includes(arr, NaN), true);
assert.equal(includes(arr, 'foo', 0), true); assert.equal(includes(arr, 'foo', 1), true); assert.equal(includes(arr, 'foo', 2), false); ```
```js / when Array#includes is not present / delete Array.prototype.includes; var shimmedIncludes = includes.shim();
assert.equal(shimmedIncludes, includes.getPolyfill()); assert.equal(arr.includes('foo', 1), includes(arr, 'foo', 1)); ```
```js / when Array#includes is present / var shimmedIncludes = includes.shim();
assert.equal(shimmedIncludes, Array.prototype.includes); assert.equal(arr.includes(1, 'foo'), includes(arr, 1, 'foo')); ```
Simply clone the repo, npm install, and run npm test