type t = ..
type t += Invalid_pin of int | Incorrect_length | Incorrect_length_for_ins | Incompatible_file_structure | Security_status_unsatisfied | Hid_required | Conditions_of_use_not_satisfied | Incorrect_data | File_not_found | Parse_error | Incorrect_params | Incorrect_class | Ins_not_supported | Memory_error | Referenced_data_not_found | Technical_problem of int | Ok | Unknown of int
val register_string_f : (t -> string option) -> unitval to_string : t -> stringval show : t -> stringval pp : Stdlib.Format.formatter -> t -> unit