SpecExample.scala

object SpecExample extends App {
  // Application code
  case class ResourceX(name: String)
  case class ResourceY(name: String)

  def createResourceX(name: String): ResourceX = { println(s"Creating $name"); ResourceX(name) }
  def createResourceY(name: String): ResourceY = { println(s"Creating $name"); ResourceY(name) }

  // Utility code for testing
  trait Closeable[R] {
    def close(res: R)
  }

  implicit object ResourceXCloseable extends Closeable[ResourceX] {
    override def close(res: ResourceX): Unit = println(s"Close $res")
  }

  implicit object ResourceYCloseable extends Closeable[ResourceY] {
    override def close(res: ResourceY): Unit = println(s"Close $res")
  }

  class ResourceWrapper[R](res: R)(implicit ev: Closeable[R]) {
    def foreach[T](block: R => T) =
      try {
        block(res)
      } finally {
        ev.close(res)
      }
  }

  implicit def wrapResource[R](res: R)(implicit ev: Closeable[R]) = new ResourceWrapper(res)

  // Test case
  for (
    x <- createResourceX("foo");
    y <- createResourceY("bar")
  ) {
    println(s"Some test cases: $x, $y")
  }
}