Book Image

Mastering JavaScript Functional Programming

By : Federico Kereki
Book Image

Mastering JavaScript Functional Programming

By: Federico Kereki

Overview of this book

Functional programming is a programming paradigm for developing software using functions. Learning to use functional programming is a good way to write more concise code, with greater concurrency and performance. The JavaScript language is particularly suited to functional programming. This book provides comprehensive coverage of the major topics in functional programming with JavaScript to produce shorter, clearer, and testable programs. You’ll delve into functional programming; including writing and testing pure functions, reducing side-effects, and other features to make your applications functional in nature. Specifically, we’ll explore techniques to simplify coding, apply recursion for loopless coding, learn ways to achieve immutability, implement design patterns, and work with data types. By the end of this book, you’ll have developed the JavaScript skills you need to program functional applications with confidence.
Table of Contents (22 chapters)
Title Page
About the Author
About the Reviewer
Customer Feedback
Connecting Functions - Pipelining and Composition
Answers to Questions


In this chapter, we have seen two different approaches (actually used by commonly available immutability libraries) to avoiding side-effects by working with immutable objects and data structures: one was based on using JavaScript's object freezing plus some special logic for cloning and the other applied the concept of persistent data structures, with methods that allowed all kinds of updates without either changing the original or requiring full cloning.

In Chapter 11, Implementing Design Patterns - The Functional Way, we will focus on a question often asked by object-oriented programmers: how are design patterns used in FP? Are they required, available, or usable? Are they still practiced but with a new focus on functions rather than on objects? We'll answer these questions with several examples showing where and how they are equivalent or they differ from the usual OOP practices.