Explore the functional programming paradigm and the different techniques for developing better algorithms, writing more concise code, and performing seamless testing
▶Book Description
Functional programming is a paradigm for developing software with better performance. It helps you write concise and testable code. To help you take your programming skills to the next level, this comprehensive book will assist you in harnessing the capabilities of functional programming with JavaScript and writing highly maintainable and testable web and server apps using functional JavaScript.
This second edition is updated and improved to cover features such as transducers, lenses, prisms and various other concepts to help you write efficient programs. By focusing on functional programming, you'll not only start to write but also to test pure functions, and reduce side effects. The book also specifically allows you to discover techniques for simplifying code and applying recursion for loopless coding. Gradually, you'll understand how to achieve immutability, implement design patterns, and work with data types for your application, before going on to learn functional reactive programming to handle complex events in your app. Finally, the book will take you through the design patterns that are relevant to functional programming.
By the end of this book, you'll have developed your JavaScript skills and have gained knowledge of the essential functional programming techniques to program effectively.
▶What You Will Learn
-Simplify JavaScript coding using function composition, pipelining, chaining, and transducing
-Use declarative coding as opposed to imperative coding to write clean JavaScript code
-Create more reliable code with closures and immutable data
-Apply practical solutions to complex programming problems using recursion
-Improve your functional code using data types, type checking, and immutability
-Understand advanced functional programming concepts such as lenses and prisms for data access
▶Key Features
-Explore this second edition updated to cover features like async functions and transducers, as well as functional reactive programming
-Enhance your functional programming (FP) skills to build web and server apps using JavaScript
-Use FP to enhance the modularity, reusability, and performance of apps
▶Who This Book Is For
This book is for JavaScript developers who want to enhance their programming skills and build efficient web applications. Frontend and backend developers who use various JavaScript frameworks and libraries like React, Angular, or Node.js will also find the book helpful. Working knowledge of ES2019 is required to grasp the concepts covered in the book easily.
▶What this book covers
In this book, we'll cover FP in a practical way; though, at times, we will mention some theoretical points:
- Chapter 1, Becoming Functional – Several Questions, discusses FP, gives reasons for its usage, and lists the tools that you'll need to take advantage of the rest of the book.
- Chapter 2, Thinking Functionally – A First Example, will provide the first example of FP by considering a common web-related problem and going over several solutions, to finally center on a functional solution.
- Chapter 3, Starting Out with Functions – A Core Concept, will go over the central concept of FP, that is, functions, and the different options available in JavaScript.
- Chapter 4, Behaving Properly – Pure Functions, will consider the concept of purity and pure functions, and demonstrate how it leads to simpler coding and easier testing.
- Chapter 5, Programming Declaratively – A Better Style, will use simple data structures to show how to produce results that work not in an imperative way, but in a declarative fashion.
- Chapter 6, Producing Functions – Higher-Order Functions, will deal with higher-order functions, which receive other functions as parameters and produce new functions as results.
- Chapter 7, Transforming Functions – Currying and Partial Application, will explore some methods for producing new and specialized functions from earlier ones.
- Chapter 8, Connecting Functions – Pipelining and Composition, will show the key concepts regarding how to build new functions by joining previously defined ones.
- Chapter 9, Designing Functions – Recursion, will look at how a key concept in FP, recursion, can be applied to designing algorithms and functions.
- Chapter 10, Ensuring Purity – Immutability, will present some tools that can help you to work in a pure fashion by providing immutable objects and data structures.
- Chapter 11, Implementing Design Patterns – The Functional Way, will show how several popular OOP design patterns are implemented (or not needed!) when you program in FP ways.
- Chapter 12, Building Better Containers – Functional Data Types, will explore some more highlevel functional patterns, introducing types, containers, functors, monads, and several other more advanced FP concepts.
-I have tried to keep the examples in this book simple and down to earth because I want to focus on the functional aspects and not on the intricacies of this or that problem. Some programming texts are geared toward learning, say, a given framework, and then work on a given problem, showing how to fully work it out with the chosen tools. (In fact, at the very beginning of planning for this book, I entertained the idea of developing an application that would use all the FP things I had in mind, but there was no way to fit all of that within a single project. Exaggerating a bit, I felt like an MD trying to find a patient on whom to apply all of his medical knowledge and treatments!) So, I have opted to show plenty of individual techniques, which can be used in multiple situations. Rather than building a house, I want to show you how to put the bricks together, how to wire things up, and so on, so that you will be able to apply whatever you need, as you see fit.
