Scalaでソート

List#sort

List(1, 3, 2).sort(_ < _) // List(1, 2, 3)

class List in scala - Scala Library

Sorting.stableSort

import scala.util.Sorting

val ar = Array(1, 3, 2)
Sorting.stableSort(ar)
ar                                                // Array(1, 2, 3)

Sorting.stableSort(ar, (a: Int, b: Int) => a > b)
ar                                                // Array(3, 2, 1)

import scala.collection.mutable
import scala.util.Sorting

val mm = mutable.Map(1 -> 70, 2 -> 50)
val sorted =                              // sorted: Array((2,50), (1,70))
  Sorting.stableSort(mm.toSeq,
    (a:(Int, Int), b:(Int, Int)) => a._2 < b._2)

object Sorting in scala.util - Scala Library
http://gist.github.com/244459