Anonymous function invocation

Anonymous functions can happen after function and method invocations, as
shown in the following example:

let adder = |x| -> |y| -> x + y
  var value = adder(1)(2)
  println(value)

  let obj = DynamicObject():
    define("adder", |this, x| -> |y| -> x + y)
  value = obj: adder(10)(20)
  println(value)
}