How to get an array of unique values from an array containing duplicates in JavaScript? [duplicate]

Question

Given a ['0','1','1','2','3','3','3'] array, the result should be ['0','1','2','3'].

Answer 1

Edited

ES6 solution:

[...new Set(a)]; 

Alternative:

Array.from(new Set(a)); 

Old response. O(n^2) (do not use it with large arrays!)

var arrayUnique = function(a) {     return a.reduce(function(p, c) {         if (p.indexOf(c) < 0) p.push(c);         return p;     }, []); };