Context.Statetype 'a t = 'a Heterogeneous_dict.keyval make : unit -> 'a Heterogeneous_dict.Type.Id.tval find : context -> 'a Heterogeneous_dict.key -> 'a optionval get : context -> 'a Heterogeneous_dict.key -> 'aval set : context -> 'a Heterogeneous_dict.Type.Id.t -> 'a option -> unit