(Program
  (Module
    (Identifier))
  (Function
    (Empty)
    (Identifier)
    ([])
    (
      (Call
        (Identifier)
        (BiDirectionalChannel
        { (Identifier)
        ->(Identifier) })
        (Empty))
      (Call
        (Identifier)
        (BiDirectionalChannel
        { (Identifier)
        ->(Identifier) })
        (Minus
          (Identifier)
          (Identifier))
        (Empty))
      (Call
        (Identifier)
        (BiDirectionalChannel
        { (Identifier)
        ->(Identifier) })
      { (Integer)
      ->(Integer) }
      { (Integer)
      ->(Integer) }
        (Empty))
      (Call
        (Identifier)
        (Map
        { (Identifier)
        ->(Identifier) }
        { (Identifier)
        ->(Identifier) })
        (Empty)))))