ES6 – the Set class

ECMAScript 2015 introduced a Set class as part of the JavaScript API. We developed our Set class based on the ES6  Set class.

Note

You can see the details of the ECMAScript 6 Set class implementation at https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set (or http://goo.gl/2li2a5 ).

Now, let's take a look at how we can use the native Set class, as well.

Let's use the same examples we used to test our Set class, as follows:

let set = new Set(); 
set.add(1); 
console.log(set.values()); //outputs @Iterator 
console.log(set.has(1));   //outputs true 
console.log(set.size);   //outputs 1 

The difference between our Set class and the ES6 Set class is that the values method returns Iterator (which you learned in Chapter 2,  Arrays ) instead of the array with the values. Another difference is that we developed a size method to return the number of values set stores. The ES6 Set class has a property named size.

We can also call the delete method to...