((output
  (((f.ml (1 0) (3 1))
    (2
     (label
      ((root (f.ml (page f.ml) 00000000000000000000000000000000) f.ml)
       (label foo-)))
     (((f.ml (1 3) (1 6)) (word Foo)) ((f.ml (2 0) (2 0)) space))))))
 (warnings
  ( "File \"f.ml\", line 2, characters 0-0:\
   \nBlank line is not allowed in '{2 ...}' (section heading).")))
