Combines a list of arrays, returning a single array with unique values, using strict equality for comparisons.
The arr-union npm package is designed to create an array of unique values, in order, from the provided arrays. It is particularly useful for combining arrays while removing duplicate entries efficiently.
Union of multiple arrays
This feature allows you to pass multiple arrays to the union function, which returns a new array that includes every unique element from the input arrays, preserving the order they appear in the input.
const union = require('arr-union');
let result = union([1, 2], [2, 3], [3, 4]);
console.log(result); // Output: [1, 2, 3, 4]Lodash's union function offers similar functionality to arr-union. It creates an array of unique values, in order, from all given arrays using SameValueZero for equality comparisons. Compared to arr-union, lodash.union is part of a larger utility library, which might be preferable for projects that require additional utility functions beyond array union.
Combines a list of arrays, returning a single array with unique values, using strict equality for comparisons.
Install with npm:
$ npm i arr-union --save
This library is 10-20 times faster and more performant than array-union.
See the benchmarks.
#1: five-arrays
array-union x 511,121 ops/sec ±0.80% (96 runs sampled)
arr-union x 5,716,039 ops/sec ±0.86% (93 runs sampled)
#2: ten-arrays
array-union x 245,196 ops/sec ±0.69% (94 runs sampled)
arr-union x 1,850,786 ops/sec ±0.84% (97 runs sampled)
#3: two-arrays
array-union x 563,869 ops/sec ±0.97% (94 runs sampled)
arr-union x 9,602,852 ops/sec ±0.87% (92 runs sampled)
var union = require('arr-union');
union(['a'], ['b', 'c'], ['d', 'e', 'f']);
//=> ['a', 'b', 'c', 'd', 'e', 'f']
Returns only unique elements:
union(['a', 'a'], ['b', 'c']);
//=> ['a', 'b', 'c']
Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.
Generate readme and API documentation with verb:
$ npm i verb && npm run docs
Or, if verb is installed globally:
$ verb
Install dev dependencies:
$ npm i -d && npm test
Jon Schlinkert
Copyright © 2016 Jon Schlinkert Released under the MIT license.
This file was generated by verb, v0.9.0, on February 23, 2016.
FAQs
Combines a list of arrays, returning a single array with unique values, using strict equality for comparisons.
The npm package arr-union receives a total of 10,793,581 weekly downloads. As such, arr-union popularity was classified as popular.
We found that arr-union demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
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