Get union of arrays

This function returns an array that contains all unique elements of two or more arrays.

JavaScript:

let union = (arr1, arr2) => [...new Set([...arr1, ...arr2])];

// Example
console.log(union([1, 2, 3], [2, 3, 4])); // [1, 2, 3, 4]
console.log(union(['a', 'b', 'c'], ['b', 'c', 'd'])); // ['a', 'b', 'c', 'd']

TypeScript:

let union = (arr1: T[], arr2: T[]): T[] => [...new Set([...arr1, ...arr2])];

// Example
console.log(union([1, 2, 3], [2, 3, 4])); // [1, 2, 3, 4]
console.log(union(['a', 'b', 'c'], ['b', 'c', 'd'])); // ['a', 'b', 'c', 'd']