Is there a way to know if the type argument passed...

# announcements

[robstoll]

Is there a way to know if the type argument passed to a fun <reified T> is a nullable type? I am asking in the context of https://youtrack.jetbrains.com/issue/KT-8947
I would like to be able to do something like:

fun <reified T> foo() = if(T::isNullable) "y" else "n"
foo<Int?>() // returns y
foo<Int>()  // return n

[Arkadii Ivanov]

Something like this?

[Arkadii Ivanov]

inline fun <reified T> isNullable(): Boolean {
return typeOf<T>().isMarkedNullable
}

[robstoll]

sweet 👍 thanks

[ilya.gorbunov]

if (null is T)
Checks whether null belongs to T type that can be only if T is nullable.

[robstoll]

Interesting, was this always like that? I remember that I tried something like that 1 year ago or so and failed. I am asking because I am not using the latest Kotlin version in some projects

[ilya.gorbunov]

I suppose it only works for reified T. For non-reified T, it would be an unchecked cast that results in always true or always false, depending on the T upper bound.