t4417.scala:11: error: constructor Pixel$mcD$sp in class Pixel$mcD$sp cannot be accessed in object Pixel
 Access to protected constructor Pixel$mcD$sp not permitted because
 enclosing object Pixel is not a subclass of
 class Pixel$mcD$sp where target is defined
  def apply(v: Double): Pixel1d = new Pixel1d(v)
                                  ^
one error found