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

Final thoughts

Let's finish this chapter with two more philosophical considerations regarding currying and partial application, which may cause a bit of a discussion:

  • First, that many libraries are just wrong as to the order of their parameters, making them harder to use
  • Second, that I don't usually even use the higher-order functions in this chapter, going for simpler JS code!

That's not probably what you were expecting by this time, so let's go over those two points in more detail, so you'll see it's not a matter of do as I say, not as I do or as the libraries do!

Parameter order

There's a problem that's common to not only functions such as Underscore's or LoDash's, mappingFunction) or _.reduce(list, reducingFunction, initialValue), but also to some that we have produced in this book, as the result of demethodize(), for example. (See the Demethodizing: turning methods into functions section of Chapter 6, Producing Functions - Higher-Order Functions, to review that higher-order function...