`sig
type bus = OBus_string.t
val validate_bus : OBus_string.validator
val is_unique : OBus_name.bus -> bool
type interface = OBus_string.t
val validate_interface : OBus_string.validator
type member = OBus_string.t
val validate_member : OBus_string.validator
type error = OBus_string.t
val validate_error : OBus_string.validator
val split : string -> string list
val ocaml_lid : string -> string
val ocaml_uid : string -> string
val haskell_lid : string -> string
val haskell_uid : string -> string
end`