two line operator, parenthesis, 3

gistfile1.scala

object ScalaHackSession {
  var a = 0                                       //> a  : Int = 0
  if (a < 10) a = a + 1
  println(a)                                      //> 1

  if (a < 10) a = (a
  + 1)
  println(a)                                      //> 2
}