Book Image

Learn ECMAScript - Second Edition

By : MEHUL MOHAN, Narayan Prusty
Book Image

Learn ECMAScript - Second Edition

By: MEHUL MOHAN, Narayan Prusty

Overview of this book

Learn ECMAScript explores implementation of the latest ECMAScript features to add to your developer toolbox, helping you to progress to an advanced level. Learn to add 1 to a variable andsafely access shared memory data within multiple threads to avoid race conditions. You’ll start the book by building on your existing knowledge of JavaScript, covering performing arithmetic operations, using arrow functions and dealing with closures. Next, you will grasp the most commonly used ECMAScript skills such as reflection, proxies, and classes. Furthermore, you’ll learn modularizing the JS code base, implementing JS on the web and how the modern HTML5 + JS APIs provide power to developers on the web. Finally, you will learn the deeper parts of the language, which include making JavaScript multithreaded with dedicated and shared web workers, memory management, shared memory, and atomics. It doesn’t end here; this book is 100% compatible with ES.Next. By the end of this book, you'll have fully mastered all the features of ECMAScript!
Table of Contents (18 chapters)
Title Page

Chapter 7. Proxies

Proxies are used to define the custom behavior of the fundamental operations on objects. Proxies are already available in programming languages such as C#, C++, and Java, but JavaScript has never had proxies. ES6 introduced the Proxy API, which lets us create proxies. In this chapter, we will look at proxies, their usage, and proxy traps. Due to the benefits of proxies, developers are using them increasingly and, therefore, it's important to learn about proxies in depth, with examples, which we will do in this chapter.

In this chapter, we'll cover:

  • Creating proxies using the Proxy API
  • Understanding what proxies are and how to use them
  • Intercepting various operations on the objects using traps
  • The different kinds of available traps
  • Some use cases of proxies