class O { default object { // Currently we consider in class O as the enclosing method of this lambda, // so we write outer class = O and enclosing method = null val f = {} } } fun box(): String { val javaClass = O.f.javaClass val enclosingMethod = javaClass.getEnclosingMethod() if (enclosingMethod != null) return "method: $enclosingMethod" val enclosingConstructor = javaClass.getEnclosingConstructor() if (enclosingConstructor != null) return "constructor: $enclosingConstructor" val enclosingClass = javaClass.getEnclosingClass() if (enclosingClass?.getName() != "O") return "enclosing class: $enclosingClass" val declaringClass = javaClass.getDeclaringClass() if (declaringClass != null) return "anonymous function has a declaring class: $declaringClass" return "OK" }