22:59 ~/Projects/Paradise2103/sandbox/src/main/scala (2.10.3)$ cat Test1.scala
class Test {
C() // referring to a companion is important
}
23:02 ~/Projects/Paradise2103/sandbox/src/main/scala (2.10.3)$ cat Test2.scala
@deprecated("", "") case class C() // C being a case class is important
23:02 ~/Projects/Paradise2103/sandbox/src/main/scala (2.10.3)$ scalac Test1.scala Test2.scala
Test2.scala:1: error: constructor definition not allowed here
@deprecated("", "") case class C()
^
one error found