object CompileError {

  import scalaz._
  import Scalaz._

  object IsItABug {

    implicit val monadWriter = EitherT.listenableMonadWriter[Writer, String, String]

    def apply(opt: Option[String]) = {

      def lift[T](o: Option[T], name: String) = o match {
        case None    ⇒ monadWriter.left[T]("The " + name + " is missing.\n")
        case Some(m) ⇒ monadWriter.right[T](m) :++>> (_ ⇒ "The " + name + " is present.\n")
      }

      def oops() =
        for {
          s ← lift(opt, "Blah") // erroneous or inaccessible type error here
          if true
        } yield "x"
    }
  }
}