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import scala.language.higherKinds
// Scala 2.10.3
trait Holds1[A]
trait Holds2[A,B]
trait Fn[F[_]]
object Fn {
  implicit def fn[F[_]] = new Fn[F] {} 
 
  implicitly[Fn[Holds1]] // 1: OK
  new Fn[({ type λ[a] = Holds2[Unit,a]})#λ] {} // 2: OK
 
  type Holds2_[a] = Holds2[Unit,a]
  implicitly[Fn[Holds2_]] // 3: OK
 
  // 4: compile error
  implicitly[Fn[({ type λ[a] = Holds2[Unit,a]})#λ]]
}
 

/opt/scala/bin/scalac: line 50: /dev/null: Permission denied
Main.scala:16: error: could not find implicit value for parameter e: Fn[[a]Holds2[Unit,a]]
  implicitly[Fn[({ type ?[a] = Holds2[Unit,a]})#?]]
            ^
one error found
spoj: The program compiled successfully, but Main.class was not found.
      Class Main should contain method: def main(args: Array[String]).

Standard output is empty