hi, how do I specify the KType `java.util.UUID!`, not `java.util.UUID` nor `java.util.UUID?`? e.g. i...

# compiler

[Stefan]

hi, how do I specify the KType java.util.UUID!, not java.util.UUID nor java.util.UUID?? e.g. in register<UUID?>(Arb.uuid())

[Sam]

Generally speaking that's not possible:

Platform types are non-denotable, meaning that you can't write them down explicitly in the language.

https://kotlinlang.org/docs/java-interop.html#null-safety-and-platform-types

[udalov]

You can trick the compiler into using the platform type by using a value from Java, even though it’s not denotable in pure Kotlin think smart:

// FILE: kotlin.kt

private inline fun <reified T> typeOfValue(@Suppress("UNUSED_PARAMETER") x: T): KType =
    typeOf<T>()

fun main() {
    println(typeOfValue(Java.platformUUIDType()))  // "java.util.UUID!"
}

// FILE: Java.java

public class Java {
    public static java.util.UUID platformUUIDType() { return null; }
}