Array.push() and unique items

Question

I have a simple case of pushing unique values into array. It looks like this:

  this.items = [];

  add(item) {
    if(this.items.indexOf(item) > -1) {
           


        

Answer 1

Using Set

this.items = new Set();
this.items.add(1);
this.items.add(2);
this.items.add(1);
this.items.add(2);

console.log(Array.from(this.items)); // [1, 2]