Book Image

Mastering JavaScript Functional Programming - Second Edition

By : Federico Kereki
Book Image

Mastering JavaScript Functional Programming - Second Edition

By: Federico Kereki

Overview of this book

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.
Table of Contents (17 chapters)
Technical Requirements


5.1. Filtering... but what? Suppose you have an array, called someArray, and you apply the following .filter() to it, which at first sight doesn't even look like valid JavaScript code. What will be in the new array and why?

 let newArray = someArray.filter(Boolean);

5.2. Generating HTML code, with restrictions: Using the filter() sequence is quite common (even allowing that sometimes you won't use all three), and we'll come back to this in the Functional design patterns section in Chapter 11, Implementing Design Patterns – The Functional Way. The problem here is how to use those functions (and no others!) to produce an unordered list of elements (<ul>...</ul>) that can later be used onscreen. Your input is an array of objects like the following (does the list of characters date me?) and you must...