Mastering High Performance with Kotlin

Top-level members

In Kotlin, we can declare variables and methods as top-level members, but not inside a class body. Let's look at the following example:

const val compileTime: Int = 5fun compileTimeFunction() = compileTime + compileTime

This code, when decompiled to Java, looks as follows:

public final class MainKt {   public static final int compileTime = 5;   public static final int compileTimeFunction() {      return 10;   }}

There's no overhead here. The MainKt class just contains two static members without <cinit>()V or static <clinit>()V methods. This is because we use the const modifier.