Skip to content

unionBy ​

Creates an array of unique values, in order, from all given arrays using a provided mapping function to determine equality.

Signature ​

typescript
function unionBy<T, U>(arr1: T[], arr2: T[], mapper: (item: T) => U): T[];

Parameters ​

  • arr1 (T[]): The first array.
  • arr2 (U[]): The second array.
  • mapper: ((item: T) => U): The function to map array elements to comparison values.

Returns ​

(T[]): A new array containing the union of unique elements from arr1 and arr2, based on the values returned by the mapping function.

Examples ​

typescript
import { 
unionBy
} from 'js-utils-es/array';
unionBy
([{
id
: 1 }, {
id
: 2 }], [{
id
: 2 }, {
id
: 3 }],
x
=>
x
.
id
);
// Returns [{ id: 1 }, { id: 2 }, { id: 3 }]

Source ​

Source • Docs • Test Case

Contributors ​

Changelog ​

No recent changes

Made with ❤️