FILE: main.kt
    public final fun <O> matNullable(x: R|(O) -> kotlin/Unit|): R|O?| {
        ^matNullable Null(null)
    }
    public final fun box(): R|kotlin/String| {
        Q|J|.R|/J.id*s|<R|kotlin/String?|>(R|/matNullable|<R|kotlin/String!|>(<L> = matNullable@fun <anonymous>(x: R|kotlin/String|): R|kotlin/Unit| <inline=NoInline>  {
            ^@matNullable Unit
        }
        )).R|kotlin/toString|()
        ^box String(OK)
    }
