sig
  type invalid_package_type =
      Parameterized_types
    | Constrained_types
    | Private_types
    | Not_with_type
    | Neither_identifier_nor_with_type
  type error =
      Unclosed of Location.t * string * Location.t * string
    | Expecting of Location.t * string
    | Not_expecting of Location.t * string
    | Applicative_path of Location.t
    | Variable_in_scope of Location.t * string
    | Other of Location.t
    | Ill_formed_ast of Location.t * string
    | Invalid_package_type of Location.t * Syntaxerr.invalid_package_type
    | Removed_string_set of Location.t
  exception Error of Syntaxerr.error
  exception Escape_error
  val location_of_error : Syntaxerr.error -> Location.t
  val ill_formed_ast : Location.t -> string -> 'a
end