implicit conversion of methods to Finagle Services

methodToFinagleServiceConversion.scala

import com.twitter.util.Future
import com.twitter.finagle.Service

//the method that we want to pass around
def foo(x:Int): Future[String] = Future.value(x.toString)

//the construct that depends on Services
def bar(service: Service[Int,String]) = service


//Can create Services by fully implementing them as below:
val x: Service[Int,String] = new Service[Int, String] {
  override def apply(request: Int) = foo(request)
}
bar(x)

//or we can do it without boiler-plate
val y: Service[Int,String] = foo _
bar(y)

//However can't pass the function directly
//bar(foo _)


//we can make use of in scope implicit to do this for us:
object Demo {

  implicit class functionOps[A,B](foo: A => Future[B]){
    def toService: Service [A,B] = new Service[A,B] {
      override def apply(request: A) = foo(request)
    }
  }

  //this works and is maybe more readable(explicit) but is ugly
  bar((foo _).toService)
}


object DemoAlt {

  implicit def functionOps[A,B](foo: A => Future[B]): Service[A,B] = new Service[A,B] {
    override def apply(request: A) = foo(request)
  }
  
  //this works implicitly and is nicer but still annoying that you have to add _
  bar(foo _)
}

In the first example... can't you just do bar(foo)?