In Kotlin, what is the idiomatic way to deal with nullable values, referencing or converting them

Question

If I have a nullable type Xyz?, I want to reference it or convert it to a non-nullable type Xyz. What is the idiomatic way of doing so in Kotlin?<

Answer 1

The previous answer is a hard act to follow, but here's one quick and easy way:

val something: Xyz = createPossiblyNullXyz() ?: throw RuntimeError("no it shouldn't be null")
something.foo() 

If it really is never null, the exception won't happen, but if it ever is you'll see what went wrong.