JSON like Scala object notation

JssonBuilder.scala

import scala.util.DynamicVariable
object JssonBuilder {
  private val status = new DynamicVariable[Map[String, Any]](null)
  class ArrowOperatorExtension(key: String) {
    //Warning: this could cause unexpected behavior
    def ->(value: Any): (String, Any) = {
      val result = (key, value)
      status.value = status.value + result
      result
    }
  }
  def %(children: => (String, Any)): Map[String, Any] = {
    status.withValue(Map[String, Any]()) {
      children
      status.value
    }
  }
  def $(elements: Any*): List[Any] = elements.toList
  implicit def string2ArrowOperatorExtension(key: String)
    : ArrowOperatorExtension = {
    new ArrowOperatorExtension(key)
  }
}

{//prevent to namespace tainted
  import JssonBuilder._
  val obj = %{
    "X" -> 1
    "Y" -> 2
    "Z" -> 4
    "nums" -> $(1, 2, 3, 4, 5,
       %{"hoge" -> 1; "foo" -> 2} //nesting is OK
    )
  }
  println(obj)
}