Scala issue

gistfile1.scala

package test

case class Address(no: Int, street: String, city: String, state: String, zip: String)

trait LabelMaker[T] {
  def toLabel(value: T): String
}

trait Plus[T] {
  def plus(a1: T, a2: T): T
}

object LabelMaker {
  implicit object AddressLabelMaker extends LabelMaker[Address] {
    def toLabel(address: Address): String = {
      import address._
      "%d %s, %s, %s - %s".format(no, street, city, state, zip)
    }
  }
}

object IntPluser {
  implicit object IntPlus extends Plus[Int] {
    def plus(a1: Int, a2: Int) = {
      a1 + a2
    }
  }
}

object StringPluser {
  implicit object StringPlus extends Plus[String] {
    def plus(a1: String, a2: String) = {
      a1 + a2
    }
  }
}


object Test {
  def printLabel[T: LabelMaker](t: T) = implicitly[LabelMaker[T]].toLabel(t)
  def plus[T: Plus](a1: T, a2: T) = implicitly[Plus[T]].plus(a1, a2)
}

//Test.printLabel(Address(100, "Monroe Street", "Denver", "CO", "80231")) --> works just fine
//Test.plus(1,2)   --> fails!
//                      error: could not find implicit value for evidence parameter of type test.Plus[Int]
//                      Test.plus(2,3)



~
~
~
~
~
~