Function0

A function of 0 parameters.

In the following example, the definition of javaVersion is a shorthand for the anonymous class definition anonfun0:

object Main extends App {
  val javaVersion = () => sys.props("java.version")

  val anonfun0 = new Function0[String] {
    def apply(): String = sys.props("java.version")
  }
  assert(javaVersion() == anonfun0())
}