Deep TreeMap conversion

deeptreemap.scala

import scala.collection.immutable.TreeMap

trait ToTreeMap[A] {
  type Result

  def treeMap(x: A): Result
}

trait LowerPriorityToTreeMap {
  implicit def plainMap[K, V](implicit ord: Ordering[K]): ToTreeMap[Map[K, V]] =
    new ToTreeMap[Map[K, V]] {
      type Result = TreeMap[K, V]

      def treeMap(x: Map[K, V]): Result = TreeMap(x.toArray: _*)
    }
}

object ToTreeMap extends LowerPriorityToTreeMap {
  implicit def nestedMap[K, V](implicit inner: ToTreeMap[V], ord: Ordering[K]): ToTreeMap[Map[K, V]] = {
    new ToTreeMap[Map[K, V]] {
      type Result = TreeMap[K, inner.Result]

      def treeMap(x: Map[K, V]): Result = TreeMap(x.mapValues(v => inner.treeMap(v)).toArray: _*)
    }
  }

  implicit class MapOps[K, V](map: Map[K, V]) {
    def asTreeMap(implicit as: ToTreeMap[Map[K, V]]) = as.treeMap(map)
  }
}

object test extends App {

  import pellucid.data.util.ToTreeMap._

  val map: Map[Int, Map[Int, Map[Int, String]]] = Map(1000 -> Map(100 -> Map(10 -> "aa", 1 -> "bb")))
  val tm: TreeMap[Int, TreeMap[Int, TreeMap[Int, String]]] = map.asTreeMap

}