val is_empty : ('a, 'b) t -> boolval add : 'a Name.t -> 'b -> ('a, 'b) t -> ('a, 'b) tval remove : 'a Name.t -> ('a, 'b) t -> ('a, 'b) tval find : 'a Name.t -> ('a, 'b) t -> 'bval find_opt : 'a Name.t -> ('a, 'b) t -> 'b optionval iter : ('a Name.t -> 'b -> unit) -> ('a, 'b) t -> unitval mapi : ('a Name.t -> 'b -> 'c) -> ('a, 'b) t -> ('a, 'c) tval fold : ('a Name.t -> 'b -> 'c -> 'c) -> ('a, 'b) t -> 'c -> 'cval bindings : ('a, 'b) t -> ('a Name.t * 'b) listval update_default : 'b -> ('b -> 'b) -> 'a Name.t -> ('a, 'b) t -> ('a, 'b) tval mem : 'a Name.t -> ('a, 'b) t -> bool