(Program
  (Package
    (Identifier))
  (Function
    (Empty)
    (Identifier)
    ([])
    (
    {+(Assignment
      {+(Identifier)+}
      {+(Identifier)+})+}
      (Assignment
      { (Identifier)
      ->(Identifier) }
      { (Identifier)
      ->([]) })
    {+(Assignment
      {+(Identifier)+}
      {+([])+})+}
    {-(Assignment
      {-(Identifier)-}
      {-([])-})-}
    {-(Assignment
      {-(Identifier)-}
      {-([])-})-})))