union

A function that combines two arrays and returns a new array containing only unique values with duplicates removed.

By default, duplicate detection is performed only for primitive values.

If the second argument iteratee function is provided, duplicate detection is based on the iteratee return value for each element.

Code

🔗 View source code

Benchmark

• hz: Operations per second
• mean: Average response time (ms)

Default

Name	hz	mean	Performance
modern-kit/union	4,409,019.08	0.0002	fastest
lodash/union	3,714,184.11	0.0003	slowest

• modern-kit/union
  • 1.19x faster than lodash/union

with iteratee

Name	hz	mean	Performance
modern-kit/union	3,801,245.65	0.0003	fastest
lodash/unionBy	2,537,527.22	0.0004	slowest

• modern-kit/union
  • 1.50x faster than lodash/unionBy

Interface

typescript

function union<T>(arr1: T[] | readonly T[], arr2: T[] | readonly T[]): T[];

function union<T, U = T>(
  arr1: T[] | readonly T[],
  arr2: T[] | readonly T[],
  iteratee?: (item: T) => U
): T[];

Usage

Basic Usage

typescript

import { union } from '@modern-kit/utils';

union([1, 2, 3, 4], [1, 2, 3, 5]); // [1, 2, 3, 4, 5]

Iteratee Usage

typescript

import { union } from '@modern-kit/utils';

const arr1 = [
  { id: 1, name: 'john' },
  { id: 2, name: 'jane' },
];
const arr2 = [
  { id: 1, name: 'john' },
  { id: 3, name: 'gromit' },
];

union(arr1, arr2, (item) => item.id);
/*
  [
    { id: 1, name: 'john' },
    { id: 2, name: 'jane' },
    { id: 3, name: 'gromit' }
  ]
*/