sig
type elt = elt
type t = elt Parameter_category.t
val none : t
val default : unit -> t
val all : unit -> t
val set_default : t -> unit
val add : string -> State.t list -> elt Parameter_category.accessor -> t
val enable_all : State.t list -> elt Parameter_category.accessor -> t
val enable_all_as : t -> unit
end