Scala Cats:如何将列表[ValidatedNel[E,a]]转换为Ior[NonEmptyList[E],列表[a]]?

我试过:

def convert[E, A](in: List[ValidatedNel[E, A]]): Ior[NonEmptyList[E], List[A]] =
    in.separate

我得到:

could not find implicit value for parameter G: cats.Bifoldable[cats.data.ValidatedNel]
[error]     in.separate

  def convert[E, A](in: List[ValidatedNel[E, A]]): Ior[NonEmptyList[E], List[A]] =
    in.traverse(_.toIor)

现在我得到了:

 could not find implicit value for evidence parameter of type cats.Applicative[G]
[error]     in.traverse(_.toIor)