val of_string : string -> tval to_string : t -> stringval parse : string -> t optionparse s is Some (a:t) if s can be a valid atom according to is_valid otherwise it is None
val print : t -> stringval of_int : int -> tval of_float : float -> tval of_bool : bool -> tval of_int64 : Stdlib.Int64.t -> tval of_digest : Stdune.Digest.t -> tval to_dyn : t -> Stdune.Dyn.t