Book Image

Mastering Reactive JavaScript

By : Erich de Souza Oliveira
Book Image

Mastering Reactive JavaScript

By: Erich de Souza Oliveira

Overview of this book

If you’re struggling to handle a large amount of data and don’t know how to improve your code readability, then reactive programming is the right solution for you. It lets you describe how your code behaves when changes happen and makes it easier to deal with real-time data. This book will teach you what reactive programming is, and how you can use it to write better applications. The book starts with the basics of reactive programming, what Reactive Extensions is, and how can you use it in JavaScript along with some reactive code using Bacon. Next, you’ll discover what an Observable and an Observer are and when to use them.You'll also find out how you can query data through operators, and how to use schedulers to react to changes. Moving on, you’ll explore the RxJs API, be introduced to the problem of data traffic (backpressure), and see how you can mitigate it. You’ll also learn about other important operators that can help improve your code readability, and you’ll see how to use transducers to compose operators. At the end of the book, you’ll get hands-on experience of using RxJs, and will create a real-time web chat using RxJs on the client and server, providing you with the complete package to master RxJs.
Table of Contents (11 chapters)

A performance comparison for JavaScript code using transducers

One of the advantages of using transducers with RxJS is the performance improvement you can get from this, so far we have just commented on this improvement, now we will add some benchmarks so you can see the performance benefits for yourself. The results presented here are based on running on my personal computer; executions on different computers might lead to different results.

The most used and famous library for running benchmarks is called benchmarks. We can install it to run in Node.js environments using npm. To add it to your project just type the following command:

npm install [email protected]

Before we start to use the library to benchmark transducers, let's see how we can use it through an example. Let's compare the difference between calling a function to sum two numbers using call or apply:

var Benchmark = require('benchmark') 
var suite = new Benchmark.Suite; 

var sum = (a,b)=>a+b; 

suite.add('Sum using call', function...