replacing all occurences of Order by Enum failed

gistfile1.scala

import scalaz.Order
import scalaz.syntax.order._

case class MyRange[A: Order](l: A, h: A){
  def myMethod(b: MyRange[A]): MyRange[A] = {
    MyRange[A](l min b.l, h max b.h)
  }
}

object MyRange {
  def myMethod[A: Order](a: MyRange[A], b: MyRange[A]): MyRange[A] = {
    MyRange[A](a.l min b.l, a.h max b.h)
  }
}


//test
import org.scalatest.FunSuite

class MyRangeSpecs extends FunSuite {

  test("test implicit in companion object") {
    val v1 = MyRange(1, 2)
    val v2 = MyRange(3, 4)
    val v3 = MyRange.myMethod(v1, v2)
    assert(v3 === MyRange(1, 4))
  }

  test("test implicit with case class method in companion object") {
    val v1 = MyRange(1, 2)
    val v2 = MyRange(3, 4)
    val v3 = v1 myMethod v2
    assert(v3 === MyRange(1, 4))
  }

  test("test BigInt range ") {
    val v1 = MyRange(BigInt(1), BigInt(2))
    val v2 = MyRange(BigInt(3), BigInt(4))
    val v3 = v1 myMethod v2
    assert(v3 === MyRange(BigInt(1), BigInt(4)))
  }


}