typelevel/cats-effect

Learning Question: I'm trying to run the cats.effect.Resource example from https://typelevel.org/cats-effect/datatypes/resource.html#example. I get value map is not a member of cats.effect.Resource[cats.effect.IO,String]. Wondering why is it looking for map not flatMap,

 // example taken from https://typelevel.org/cats-effect/datatypes/resource.html#example
  test("cats Resource") {

    import cats.effect.{IO, Resource}
    import cats.implicits._

    def mkResource(data: String): Resource[IO, String] = {
      val acquire = IO(println(s"Acquiring $data")) *> IO.pure(data)

      def release(res: String) = IO(println(s"Releasing $res"))

      Resource.make(acquire)(release)
    }

    val out: Resource[IO, String] = mkResource("outer")
    val in: Resource[IO, String] = mkResource("inner")

//    val rr = out.flatMap { a =>
//      in.flatMap { b =>
//        Resource.pure((a, b))
//      }
//    }

    //    out.map { o =>
    //      in.map { i =>
    //        (o, i)
    //      }
    //    }

    val r = for {
      outer <- out
      inner <- in
    } yield (outer, inner)

    r.use { case (x, y) => IO(println(s"Using $x and $y")) }.unsafeRunSync

  }

Error