1 # arr-diff [![NPM version](https://img.shields.io/npm/v/arr-diff.svg?style=flat)](https://www.npmjs.com/package/arr-diff) [![NPM monthly downloads](https://img.shields.io/npm/dm/arr-diff.svg?style=flat)](https://npmjs.org/package/arr-diff) [![Linux Build Status](https://img.shields.io/travis/jonschlinkert/arr-diff.svg?style=flat&label=Travis)](https://travis-ci.org/jonschlinkert/arr-diff)
3 > Returns an array with only the unique values from the first array, by excluding all values from additional arrays using strict equality for comparisons.
7 Install with [npm](https://www.npmjs.com/):
10 $ npm install --save arr-diff
13 Install with [yarn](https://yarnpkg.com):
19 Install with [bower](https://bower.io/)
22 $ bower install arr-diff --save
27 Returns the difference between the first array and additional arrays.
30 var diff = require('arr-diff');
32 var a = ['a', 'b', 'c', 'd'];
35 console.log(diff(a, b))
41 This library versus [array-differ](https://github.com/sindresorhus/array-differ), on April 14, 2017:
44 Benchmarking: (4 of 4)
50 # benchmark/fixtures/long-dupes.js (100804 bytes)
51 arr-diff-3.0.0 x 822 ops/sec ±0.67% (86 runs sampled)
52 arr-diff-4.0.0 x 2,141 ops/sec ±0.42% (89 runs sampled)
53 array-differ x 708 ops/sec ±0.70% (89 runs sampled)
55 fastest is arr-diff-4.0.0
57 # benchmark/fixtures/long.js (94529 bytes)
58 arr-diff-3.0.0 x 882 ops/sec ±0.60% (87 runs sampled)
59 arr-diff-4.0.0 x 2,329 ops/sec ±0.97% (83 runs sampled)
60 array-differ x 769 ops/sec ±0.61% (90 runs sampled)
62 fastest is arr-diff-4.0.0
64 # benchmark/fixtures/med.js (708 bytes)
65 arr-diff-3.0.0 x 856,150 ops/sec ±0.42% (89 runs sampled)
66 arr-diff-4.0.0 x 4,665,249 ops/sec ±1.06% (89 runs sampled)
67 array-differ x 653,888 ops/sec ±1.02% (86 runs sampled)
69 fastest is arr-diff-4.0.0
71 # benchmark/fixtures/short.js (60 bytes)
72 arr-diff-3.0.0 x 3,078,467 ops/sec ±0.77% (93 runs sampled)
73 arr-diff-4.0.0 x 9,213,296 ops/sec ±0.65% (89 runs sampled)
74 array-differ x 1,337,051 ops/sec ±0.91% (92 runs sampled)
76 fastest is arr-diff-4.0.0
83 * [arr-flatten](https://www.npmjs.com/package/arr-flatten): Recursively flatten an array or arrays. This is the fastest implementation of array flatten. | [homepage](https://github.com/jonschlinkert/arr-flatten "Recursively flatten an array or arrays. This is the fastest implementation of array flatten.")
84 * [array-filter](https://www.npmjs.com/package/array-filter): Array#filter for older browsers. | [homepage](https://github.com/juliangruber/array-filter "Array#filter for older browsers.")
85 * [array-intersection](https://www.npmjs.com/package/array-intersection): Return an array with the unique values present in _all_ given arrays using strict equality… [more](https://github.com/jonschlinkert/array-intersection) | [homepage](https://github.com/jonschlinkert/array-intersection "Return an array with the unique values present in _all_ given arrays using strict equality for comparisons.")
89 Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](../../issues/new).
93 | **Commits** | **Contributor** |
95 | 33 | [jonschlinkert](https://github.com/jonschlinkert) |
96 | 2 | [paulmillr](https://github.com/paulmillr) |
100 _(This project's readme.md is generated by [verb](https://github.com/verbose/verb-generate-readme), please don't edit the readme directly. Any changes to the readme must be made in the [.verb.md](.verb.md) readme template.)_
102 To generate the readme, run the following command:
105 $ npm install -g verbose/verb#dev verb-generate-readme && verb
110 Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:
113 $ npm install && npm test
120 * [github/jonschlinkert](https://github.com/jonschlinkert)
121 * [twitter/jonschlinkert](https://twitter.com/jonschlinkert)
125 Copyright © 2017, [Jon Schlinkert](https://github.com/jonschlinkert).
126 Released under the [MIT License](LICENSE).
130 _This file was generated by [verb-generate-readme](https://github.com/verbose/verb-generate-readme), v0.5.0, on April 14, 2017._