Creating a set

The current implementation of JavaScript is based on ECMAScript 5.1 (supported by modern browsers) published on June 2011. It contains the Array class implementation that we covered in earlier chapters. ECMAScript 6 (a work in progress, expected to be released in March 2015 at the time of writing this book) contains an implementation of the 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).

The class we are going to implement in this chapter is based on the Set implementation of ECMAScript 6.

This is the skeleton of our Set class:

function Set() {
    var items = {};
}

A very important detail is that we are using an object to represent our set ( items ) instead of an array. But we could also use an array to do this implementation. Let's use an object to implement things a little bit differently and learn new ways of implementing data...