Object can be functions in Scala

imafunction.scala

scala> object ImaFunction {
     |   def apply() { println("I am a function") }
     | }
defined module ImaFunction

scala> case class Sois(name: String) {
     |   def apply() { printf("%s is also a function", name) }
     | }
defined class Sois

scala> ImaFunction()
I am a function

scala> val x = Sois("x")
x: Sois = Sois(x)

scala> x()
x is also a function