test/files/neg/t7872c.scala


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object coinv {
  def up[F[+_]](fa: F[String]): F[Object] = fa
  def down[F[-_]](fa: F[Object]): F[String] = fa
 
  up(List("hi"))
  // [error] type A is covariant, but type _ is declared contravariant
  down(List('whatever: Object))
}