UFile (package = ) [public final class DefaultParameterValuesKt {...]
    UClass (name = DefaultParameterValuesKt) [public final class DefaultParameterValuesKt {...}]
        UMethod (name = foo) [public static final fun foo(a: int, foo: java.lang.String) : void {...}]
            UParameter (name = a) [var a: int = 1]
                ULiteralExpression (value = 1) [1] = (long)1
            UParameter (name = foo) [var foo: java.lang.String = null]
                ULiteralExpression (value = null) [null] = null
            UBlockExpression [{...}] = Undetermined
