Articles

Data Classes and Destructuring

It's easy to use data classes to give your objects superpowers like value equality, a readable toString() implementation, the ability to easily copy values, and the ability to be destructured. In this chapter, we'll learn what they are, how to declare them, and when to use them!

Abstract and Open Classes

In this chapter, we'll see how we can create subtypes from abstract classes and open classes. Impress your friends with big words like inheritance and polymorphism!

Introduction to Class Delegation

Use Kotlin’s class delegation feature to forward function calls from one object to another - without all the usual boilerplate!

Introduction to Interfaces

In Kotlin, interfaces are one way to give a class more than one type at the same time. In this chapter, learn about interfaces and implementations, plus smart casts, interface inheritance, multiple interfaces, and default implementations.

Scopes and Scope Functions

Kotlin's scope functions - with(), run(), let(), also(), and apply() - introduce a new scope where an object can be easily used. Learn about two different kinds of scopes and how they affect visibility. Then, explore all five scope functions, and learn how shadowing affects implicit receivers.