Scala Unsigned test

passeraを使って以下のように書けますけど、ULongが-値になってしまったりします。

Passera: https://github.com/nystrom/scala-unsigned

import passera.unsigned._
import passera.numerics._

object Short {
    def apply(a:Int):Short = a.toShort
    def apply(a:UInt):Short = a.toShort
    def apply(a:Long):Short = a.toShort
    def apply(a:ULong):Short = a.toShort
}
object UShort {
  def apply(a:UByte):UShort = a.toUShort
  def apply(a:UInt):UShort = a.toUShort
  def apply(a:ULong):UShort = a.toUShort
  def apply(a:Int):UShort = a.toUShort
  def apply(a:Long):UShort = a.toUShort
}
object Long {
    def apply(a:Int):Long = a.toLong
    def apply(a:UInt):Long = a.toLong
    def apply(a:ULong):Long = a.toLong
}
object ULong {
  def apply(a:UInt):ULong = a.toULong
  def apply(a:ULong):ULong = a.toULong
  def apply(a:Int):ULong = a.toULong
  def apply(a:Long):ULong = a.toULong
}

object t2 {
  val zero = 0.toUInt
    def main(args:Array[String]) {

      println("short test")
      println(UShort(0xffff))
      println(UShort(UShort(0xffff)+UShort(0xffff)).toHexString)
      println(Short(Short(0xffff)+Short(0xffff)))
      println(Short(UShort(UShort(0xffff)+UShort(0xffff))))
      println(Short(111L))
      println(ULong(0x7fffffffffffffffL).toString)
      println(ULong(0x8000000000000000L).toString)
      println(ULong(0xffffffffffffffffL).toString)
    }
}