play.scala

//It is often useful to mark the request parameter as implicit so it can be implicitly used by other APIs that need it
Action { implicit request =>
  Ok("Got request [" + request + "]")
}

// Q1: "it can be implicitly used by other APIs" --> Any examples?
// Q2: If the parameter of a method is marked "implicit", client needn't 
//     provide such parameter since the compiler will find it themselves, right?
//     But I'm not able to apply this rule to the above example. 
//     What if Action is called without any parameter, i.e. " Action() "?
//     What will happen?