sig
  type t =
      Illegal_character of char
    | Illegal_escape of string
    | Unterminated_comment
    | Unterminated_string
    | Unterminated_quotation
    | Unterminated_antiquot
    | Unterminated_string_in_comment
    | Comment_start
    | Comment_not_end
    | Literal_overflow of string
  exception E of Camlp4.Struct.Lexer.Make.Error.t
  val print : Format.formatter -> Camlp4.Struct.Lexer.Make.Error.t -> unit
  val to_string : Camlp4.Struct.Lexer.Make.Error.t -> string
end