`sig type t val min : Uchar.t val max : Uchar.t val succ : Uchar.t -> Uchar.t val pred : Uchar.t -> Uchar.t val is_valid : int -> bool val of_int : int -> Uchar.t val unsafe_of_int : int -> Uchar.t val to_int : Uchar.t -> int val is_char : Uchar.t -> bool val of_char : char -> Uchar.t val to_char : Uchar.t -> char val unsafe_to_char : Uchar.t -> char val equal : Uchar.t -> Uchar.t -> bool val compare : Uchar.t -> Uchar.t -> int val hash : Uchar.t -> int val dump : Format.formatter -> Uchar.t -> unit end`