Book Image

JavaScript Concurrency

By : Adam Boduch
Book Image

JavaScript Concurrency

By: Adam Boduch

Overview of this book

Concurrent programming may sound abstract and complex, but it helps to deliver a better user experience. With single threaded JavaScript, applications lack dynamism. This means that when JavaScript code is running, nothing else can happen. The DOM can’t update, which means the UI freezes. In a world where users expect speed and responsiveness – in all senses of the word – this is something no developer can afford. Fortunately, JavaScript has evolved to adopt concurrent capabilities – one of the reasons why it is still at the forefront of modern web development. This book helps you dive into concurrent JavaScript, and demonstrates how to apply its core principles and key techniques and tools to a range of complex development challenges. Built around the three core principles of concurrency – parallelism, synchronization, and conservation – you’ll learn everything you need to unlock a more efficient and dynamic JavaScript, to lay the foundations of even better user experiences. Throughout the book you’ll learn how to put these principles into action by using a range of development approaches. Covering everything from JavaScript promises, web workers, generators and functional programming techniques, everything you learn will have a real impact on the performance of your applications. You’ll also learn how to move between client and server, for a more frictionless and fully realized approach to development. With further guidance on concurrent programming with Node.js, JavaScript Concurrency is committed to making you a better web developer. The best developers know that great design is about more than the UI – with concurrency, you can be confident every your project will be expertly designed to guarantee its dynamism and power.
Table of Contents (17 chapters)
JavaScript Concurrency
About the Author
About the Reviewer

Infinite sequences

Some sequences are infinite, prime numbers, Fibonacci numbers, odd numbers, and so on. Infinite sequences aren't limited to sets of numbers; more abstract notions can be considered infinite. For example, a set of stings that repeats itself infinitely, a Boolean value that toggles infinitely, and so on. In this section, we'll explore how generators make it possible for us to work with infinite sequences.

No end in sight

Allocating items from an infinite sequence isn't practical from a memory consumption point of view. In fact, it's not even possible to allocate the whole sequence—it's infinite. Memory is finite. So, it's better to simply sidestep the whole allocation problem entirely and use a generator to yield the values from the sequence as we need them. At any given point in time, our application is only going to use a tiny slice of the infinite sequence. Here's a visualization of what's used from an infinite sequence versus the potential size of these sequences:

As we...