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post.scala

type NoWrap[ScalaValue] = ScalaValue

  val interpret = new Language[NoWrap] {
    override def number(v: Int): NoWrap[Int] = v
    override def increment(a: NoWrap[Int]): NoWrap[Int] = a + 1
    override def add(a: NoWrap[Int], b: NoWrap[Int]): NoWrap[Int] = a + b

    override def text(v: String): NoWrap[String] = v
    override def toUpper(a: NoWrap[String]): NoWrap[String] = a.toUpperCase
    override def concat(a: NoWrap[String], b: NoWrap[String]): NoWrap[String] = a + " " + b

    override def toString(v: NoWrap[Int]): NoWrap[String] = v.toString
  }