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

Chapter 4. Behaving Properly - Pure Functions

In  Chapter 3, Starting Out with Functions - A Core Concept, we considered functions as the key elements in FP, went into detail about arrow functions, and introduced some concepts such as injection, callbacks, polyfilling, and stubbing. Now, in this chapter, we'll have the opportunity to revisit or apply some of those ideas, while we also...

  • Consider the notion of purity, and why we should care about pure functions
  • Examine the concept of Referential Transparency
  • Recognize the problems implied by side effects
  • Show some advantages of pure functions
  • Describe the main causes of impure functions
  • Find ways to minimize the number of impure functions
  • Focus on ways of testing both pure and impure functions