Kotlin in Action

Chapter 9. Generics

This chapter covers

• Declaring generic functions and classes
• Type erasure and reified type parameters
• Declaration-site and use-site variance

You’ve already seen a few code examples that use generics in this book. The basic concepts of declaring and using generic classes and functions in Kotlin are similar to Java, so the earlier examples should have been clear without a detailed explanation. In this chapter, we’ll return to some of the examples and look at them in more detail.

We’ll then go deeper into the topic of generics and explore new concepts introduced in Kotlin, such as reified type parameters and declaration-site variance. These concepts may be novel to you, but don’t worry; the chapter covers them thoroughly. ...