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

A functional solution to our problem

Let's try to be more general; after all, requiring that some function or other be executed only once isn't that outlandish, and may be required elsewhere! Let's lay down some principles:

  • The original function (the one that may be called only once) should do whatever it is expected to do and nothing else.
  • We don't want to modify the original function in any way.
  • We need to have a new function that will call the original one only once.
  • We want a general solution that we can apply to any number of original functions.
The first principle listed previously is the single responsibility principle (the S in S.O.L.I.D.), which states that every function should be responsible for a single functionality. For more on S.O.L.I.D., check the article by Uncle Bob (Robert C. Martin, who wrote the five principles) at http://butunclebob...