130 lines
		
	
	
		
			4.4 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			130 lines
		
	
	
		
			4.4 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
# arr-diff [](https://www.npmjs.com/package/arr-diff) [](https://npmjs.org/package/arr-diff) [](https://travis-ci.org/jonschlinkert/arr-diff)
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> Returns an array with only the unique values from the first array, by excluding all values from additional arrays using strict equality for comparisons.
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## Install
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Install with [npm](https://www.npmjs.com/):
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```sh
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$ npm install --save arr-diff
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```
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Install with [yarn](https://yarnpkg.com):
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```sh
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$ yarn add arr-diff
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```
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Install with [bower](https://bower.io/)
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```sh
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$ bower install arr-diff --save
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```
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## Usage
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Returns the difference between the first array and additional arrays.
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```js
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var diff = require('arr-diff');
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var a = ['a', 'b', 'c', 'd'];
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var b = ['b', 'c'];
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console.log(diff(a, b))
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//=> ['a', 'd']
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```
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## Benchmarks
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This library versus [array-differ](https://github.com/sindresorhus/array-differ), on April 14, 2017:
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```
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Benchmarking: (4 of 4)
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 · long-dupes
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 · long
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 · med
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 · short
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# benchmark/fixtures/long-dupes.js (100804 bytes)
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  arr-diff-3.0.0 x 822 ops/sec ±0.67% (86 runs sampled)
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  arr-diff-4.0.0 x 2,141 ops/sec ±0.42% (89 runs sampled)
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  array-differ x 708 ops/sec ±0.70% (89 runs sampled)
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  fastest is arr-diff-4.0.0
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# benchmark/fixtures/long.js (94529 bytes)
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  arr-diff-3.0.0 x 882 ops/sec ±0.60% (87 runs sampled)
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  arr-diff-4.0.0 x 2,329 ops/sec ±0.97% (83 runs sampled)
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  array-differ x 769 ops/sec ±0.61% (90 runs sampled)
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  fastest is arr-diff-4.0.0
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# benchmark/fixtures/med.js (708 bytes)
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  arr-diff-3.0.0 x 856,150 ops/sec ±0.42% (89 runs sampled)
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  arr-diff-4.0.0 x 4,665,249 ops/sec ±1.06% (89 runs sampled)
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  array-differ x 653,888 ops/sec ±1.02% (86 runs sampled)
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  fastest is arr-diff-4.0.0
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# benchmark/fixtures/short.js (60 bytes)
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  arr-diff-3.0.0 x 3,078,467 ops/sec ±0.77% (93 runs sampled)
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  arr-diff-4.0.0 x 9,213,296 ops/sec ±0.65% (89 runs sampled)
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  array-differ x 1,337,051 ops/sec ±0.91% (92 runs sampled)
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  fastest is arr-diff-4.0.0
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```
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## About
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### Related projects
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* [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.")
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* [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.")
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* [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.")
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### Contributing
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Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](../../issues/new).
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### Contributors
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| **Commits** | **Contributor** | 
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| --- | --- |
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| 33 | [jonschlinkert](https://github.com/jonschlinkert) |
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| 2 | [paulmillr](https://github.com/paulmillr) |
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### Building docs
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_(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.)_
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To generate the readme, run the following command:
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```sh
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$ npm install -g verbose/verb#dev verb-generate-readme && verb
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```
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### Running tests
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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:
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```sh
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$ npm install && npm test
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```
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### Author
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**Jon Schlinkert**
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* [github/jonschlinkert](https://github.com/jonschlinkert)
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* [twitter/jonschlinkert](https://twitter.com/jonschlinkert)
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### License
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Copyright © 2017, [Jon Schlinkert](https://github.com/jonschlinkert).
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Released under the [MIT License](LICENSE).
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***
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_This file was generated by [verb-generate-readme](https://github.com/verbose/verb-generate-readme), v0.5.0, on April 14, 2017._ |