Just wanted to play around with insertion sort to use for loops and learning more about Scala for loop conditions. Which is why I ended up implementing the insert with a while loop.

insertionsort.scala

import Ordering.Implicits._

def insertionSort[T:Ordering](a: Array[T]) : Unit = {
  for( i <- 1 until a.length) insert(a, i-1, a(i))
}

def insert[T:Ordering](a: Array[T], rightIndex: Int, x: T) {
  var i = rightIndex
  while (i >= 0 && a(i) > x)  {
      a(i+1) = a(i)
      i -= 1
  }

  a(i + 1) = x

}