Mastering High Performance with Kotlin

Compile-time constants

Kotlin is a more object-oriented language than Java because Kotlin doesn't have primitive types, static fields, or static functions. But it's not a secret that these can improve performance. In this section and the next section, we'll look at examples that will help you understand some nuances of Kotlin related to primitive types, static fields, and static functions.

A compile-time constant is a read-only variable that's initialized during compilation. It has to meet the following requirements:

• It has to be declared as top-level or a member of an object
• It has to be initialized with a string value of a primitive type
• It can't have a getter or setter

Let's look at the following example:

const val compileTime: Int = ...