How to add only unique elements to an array?

Question

JavaScript

What is an efficient way (there are probably many) to add only unique elements to an array, avoiding duplicates? Interested in the native way and, if there is lodash. Both methods are useful. Thank you.

Answer 1

Set objects allow you to store unique values ​​of any type, both primitives and other types of objects.
Syntax
https://developer.mozilla.org/en/docs/Web/JavaScript...

Answer 2

if (a.indexOf(x) === -1) a.push(x);