Node.Map
type key = t
type 'a t
val is_empty : 'a t -> bool
val empty : 'a t
val add : key -> 'a -> 'a t -> 'a t
val mem : key -> 'a t -> bool
val find : key -> 'a t -> 'a
val remove : key -> 'a t -> 'a t
val compare : ( 'a -> 'a -> int ) -> 'a t -> 'a t -> int
val equal : ( 'a -> 'a -> bool ) -> 'a t -> 'a t -> bool
val iter : ( key -> 'a -> unit ) -> 'a t -> unit
val map : ( key -> 'a -> 'b ) -> 'a t -> 'b t
val mapf : ( key -> 'a -> 'b option ) -> 'a t -> 'b t
val mapq : ( key -> 'a -> 'a option ) -> 'a t -> 'a t
val filter : ( key -> 'a -> bool ) -> 'a t -> 'a t
val partition : ( key -> 'a -> bool ) -> 'a t -> 'a t * 'a t
val fold : ( key -> 'a -> 'b -> 'b ) -> 'a t -> 'b -> 'b
val union : ( key -> 'a -> 'a -> 'a ) -> 'a t -> 'a t -> 'a t
val inter : ( key -> 'a -> 'b -> 'c ) -> 'a t -> 'b t -> 'c t
val interf : ( key -> 'a -> 'b -> 'c option ) -> 'a t -> 'b t -> 'c t
val interq : ( key -> 'a -> 'a -> 'a option ) -> 'a t -> 'a t -> 'a t
val diffq : ( key -> 'a -> 'a -> 'a option ) -> 'a t -> 'a t -> 'a t
val merge : ( key -> 'a option -> 'b option -> 'c option ) -> 'a t -> 'b t -> 'c t
val iter2 : ( key -> 'a option -> 'b option -> unit ) -> 'a t -> 'b t -> unit
val subset : ( key -> 'a -> 'b -> bool ) -> 'a t -> 'b t -> bool
val insert : ( key -> 'a -> 'a -> 'a ) -> key -> 'a -> 'a t -> 'a t
insert (fun key v old -> ...) key v map
val change : ( key -> 'b -> 'a option -> 'a option ) -> key -> 'b -> 'a t -> 'a t