Book Image

Functional Kotlin

Book Image

Functional Kotlin

Overview of this book

Functional programming makes your application faster, improves performance, and increases your productivity. Kotlin supports many of the popular and advanced functional features of functional languages. This book will cover the A-Z of functional programming in Kotlin. This book bridges the language gap for Kotlin developers by showing you how to create and consume functional constructs in Kotlin. We also bridge the domain gap by showing how functional constructs can be applied in business scenarios. We’ll take you through lambdas, pattern matching, immutability, and help you develop a deep understanding of the concepts and practices of functional programming. If you want learn to address problems using Recursion, Koltin has support for it as well. You’ll also learn how to use the funKtionale library to perform currying and lazy programming and more. Finally, you’ll learn functional design patterns and techniques that will make you a better programmer.By the end of the book, you will be more confident in your functional programming skills and will be able to apply them while programming in Kotlin.
Table of Contents (22 chapters)
Title Page
Copyright and Credits
Dedication
Packt Upsell
Contributors
Preface
Index

Chapter 3. Immutability - It's Important

So, we are in the third chapter of, Functional Kotlin. In this chapter, we are going to discuss immutability. Immutability is probably the most important aspect of functional programming; actually, not only in functional programming, but OOP also gives some room to nurture immutability with immutable objects. So, why is it so important? What does it mean? How can we implement immutability in Kotlin? Let's answer these questions in this chapter.

The following are the points we are going to cover in this chapter:

  • What is immutability?
  • The advantages of immutability
  • How to implement immutability in Kotlin?
  • Immutability in variables
  • val versus var
  • val and const val—are they truly immutable?
  • Compiler optimization
  • Immutable collections
  • The disadvantages of immutability