我想测量io容器中经过的时间。使用普通呼叫或期货相对容易（例如下面的代码）

class MonitoringComponentSpec extends FunSuite with Matchers with ScalaFutures {

  import scala.concurrent.ExecutionContext.Implicits.global

  def meter[T](future: Future[T]): Future[T] = {
    val start = System.currentTimeMillis()
    future.onComplete(_ => println(s"Elapsed ${System.currentTimeMillis() - start}ms"))
    future
  }

  def call(): Future[String] = Future {
    Thread.sleep(500)
    "hello"
  }

  test("metered call") {
    whenReady(meter(call()), timeout(Span(550, Milliseconds))) { s =>
      s should be("hello")
    }
  }
}

但不知道如何 Package io调用

def io_meter[T](effect: IO[T]): IO[T] = {
    val start = System.currentTimeMillis()
    ???
  }

  def io_call(): IO[String] = IO.pure {
    Thread.sleep(500)
    "hello"
  }

  test("metered io call") {
    whenReady(meter(call()), timeout(Span(550, Milliseconds))) { s =>
      s should be("hello")
    }
  }

谢谢您！