(Program
  (Comprehension
  { (Identifier)
  ->(Identifier) }
    (
      (
        (
        { (Identifier)
        ->(Identifier) })
      { (Identifier)
      ->(Identifier) })))
  (Comprehension
  { (Plus
    {-(Identifier)-}
    {-(Integer)-})
  ->(Identifier) }
    (
      (
        (
        { (Identifier)
        ->(Identifier) })
      { (Identifier)
      ->(Identifier) }))))