Helper function for simple method benchmarking

ScalaBenchmark.scala

// Source: https://stackoverflow.com/questions/9160001/how-to-profile-methods-in-scala
def benchmark[R](runs: Int, block: => R) = {
    def print_result(s: String, ns: Long) = {
      val formatter = java.text.NumberFormat.getIntegerInstance
      println("%-16s".format(s) + formatter.format(ns) + " ns")
    }

    var t0 = System.nanoTime()
    var result = block    // call-by-name
    var t1 = System.nanoTime()

    print_result("First Run", (t1 - t0))

    var lst = for (i <- 1 to runs) yield {
      t0 = System.nanoTime()
      result = block    // call-by-name
      t1 = System.nanoTime()
      (t1 - t0).toLong
    }

    print_result("Max", lst.max)
    print_result("Min", lst.min)
    print_result("Avg", (lst.sum / lst.length))
}