Book Image

Professional JavaScript

By : Hugo Di Francesco, Siyuan Gao, Vinicius Isola, Philip Kirkbride
Book Image

Professional JavaScript

By: Hugo Di Francesco, Siyuan Gao, Vinicius Isola, Philip Kirkbride

Overview of this book

In depth knowledge of JavaScript makes it easier to learn a variety of other frameworks, including React, Angular, and related tools and libraries. This book is designed to help you cover the core JavaScript concepts you need to build modern applications. You'll start by learning how to represent an HTML document in the Document Object Model (DOM). Then, you'll combine your knowledge of the DOM and Node.js to create a web scraper for practical situations. As you read through further lessons, you'll create a Node.js-based RESTful API using the Express library for Node.js. You'll also understand how modular designs can be used for better reusability and collaboration with multiple developers on a single project. Later lessons will guide you through building unit tests, which ensure that the core functionality of your program is not affected over time. The book will also demonstrate how constructors, async/await, and events can load your applications quickly and efficiently. Finally, you'll gain useful insights into functional programming concepts such as immutability, pure functions, and higher-order functions. By the end of this book, you'll have the skills you need to tackle any real-world JavaScript development problem using a modern JavaScript approach, both for the client and server sides.
Table of Contents (12 chapters)

10. Functional Programming with JavaScript

Learning Objectives

By the end of this chapter, you will be able to:

  • Use pure functions in Redux reducers and selectors
  • Solve advanced function testing situations
  • Apply currying, partial application, and closures in modern JavaScript applications
  • Implement a compose function for use in a backend for frontend (BFF) built with micro
  • Apply JavaScript built-ins to write in an immutable style specifically in a Redux application
  • Implement a query and a mutation in the context of a BFF using GraphQL
  • Select from three approaches to handle side effects in a React/Redux application

In this chapter, you will learn about the concepts of functional programming, how to apply them in JavaScript, and identify them "in the wild" in popular libraries such as React, Redux, and systems such as the GraphQL query language.