ES6: Using Set For Unique Arrays

In the past, getting unique values meant pulling an external library or creating your own. Now, you can easily do that with Set and Array.from{:js}.

const books = ['Matilda', 'Charlie and the Chocolate Factory', 'Matilda', 'James and the Giant Peach', 'Matilda']
const uniqueBooks = Array.from(new Set(books))
// => ['Matilda', 'Charlie and the Chocolate Factory', 'James and the Giant Peach']

Set{:js} lets you store unique values and accepts any Object{:js} or primitive to be passed in to it’s initializer. When the data passed in has multiple items, it strips them out automatically.

Spread Operator

A simpler syntax exists if you use the spread operator:

const books = ['Matilda', 'Charlie and the Chocolate Factory', 'Matilda', 'James and the Giant Peach', 'Matilda']
const uniqueBooks = [...new Set(books)]