# Module type Core_map_intf.Accessors2

    module type Accessors2 = sig .. end

    type ('a, 'b) t

    type ('a, 'b) tree

    val invariants : ('a, 'b) t -> bool

    val is_empty : ('a, 'b) t -> bool

    val length : ('a, 'b) t -> int

    val add : ('a, 'b) t ->
           key:'a -> data:'b -> ('a, 'b) t

    val add_multi : ('a, 'b list) t ->
           key:'a -> data:'b -> ('a, 'b list) t

    val change : ('a, 'b) t ->
           'a -> ('b option -> 'b option) -> ('a, 'b) t

    val find : ('a, 'b) t -> 'a -> 'b option

    val find_exn : ('a, 'b) t -> 'a -> 'b

    val remove : ('a, 'b) t ->
           'a -> ('a, 'b) t

    val mem : ('a, 'b) t -> 'a -> bool

    val iter : ('a, 'b) t -> f:(key:'a -> data:'b -> unit) -> unit

    val iter2 : ('a, 'b) t ->
           ('a, 'c) t ->
           f:(key:'a -> data:[ `Both of 'b * 'c | `Left of 'b | `Right of 'c ] -> unit) ->
           unit

    val map : ('a, 'b) t ->
           f:('b -> 'c) -> ('a, 'c) t

    val mapi : ('a, 'b) t ->
           f:(key:'a -> data:'b -> 'c) -> ('a, 'c) t

    val fold : ('a, 'b) t ->
           init:'c -> f:(key:'a -> data:'b -> 'c -> 'c) -> 'c

    val fold_right : ('a, 'b) t ->
           init:'c -> f:(key:'a -> data:'b -> 'c -> 'c) -> 'c

    val filter : ('a, 'b) t ->
           f:(key:'a -> data:'b -> bool) -> ('a, 'b) t

    val filter_map : ('a, 'b) t ->
           f:('b -> 'c option) -> ('a, 'c) t

    val filter_mapi : ('a, 'b) t ->
           f:(key:'a -> data:'b -> 'c option) -> ('a, 'c) t

    val compare_direct : ('b -> 'b -> int) ->
           ('a, 'b) t ->
           ('a, 'b) t -> int

    val equal : ('b -> 'b -> bool) ->
           ('a, 'b) t ->
           ('a, 'b) t -> bool

    val keys : ('a, 'b) t -> 'a list

    val data : ('a, 'b) t -> 'b list

    val to_alist : ('a, 'b) t -> ('a * 'b) list

    val validate : name:('a -> string) ->
           'b Validate.check -> ('a, 'b) t Validate.check

    val merge : ('a, 'b) t ->
           ('a, 'c) t ->
           f:(key:'a -> [ `Both of 'b * 'c | `Left of 'b | `Right of 'c ] -> 'd option) ->
           ('a, 'd) t

    val symmetric_diff : ('a, 'b) t ->
           ('a, 'b) t ->
           data_equal:('b -> 'b -> bool) ->
           ('a * [ `Left of 'b | `Right of 'b | `Unequal of 'b * 'b ]) Sequence.t

    val min_elt : ('a, 'b) t -> ('a * 'b) option

    val min_elt_exn : ('a, 'b) t -> 'a * 'b

    val max_elt : ('a, 'b) t -> ('a * 'b) option

    val max_elt_exn : ('a, 'b) t -> 'a * 'b

    val for_all : ('a, 'b) t -> f:('b -> bool) -> bool

    val exists : ('a, 'b) t -> f:('b -> bool) -> bool

    val split : ('a, 'b) t ->
           'a ->
           ('a, 'b) t * ('a * 'b) option *
           ('a, 'b) t

    val fold_range_inclusive : ('a, 'b) t ->
           min:'a -> max:'a -> init:'c -> f:(key:'a -> data:'b -> 'c -> 'c) -> 'c

    val range_to_alist : ('a, 'b) t -> min:'a -> max:'a -> ('a * 'b) list

    val closest_key : ('a, 'b) t ->
           [ `Greater_or_equal_to | `Greater_than | `Less_or_equal_to | `Less_than ] ->
           'a -> ('a * 'b) option

    val nth : ('a, 'b) t -> int -> ('a * 'b) option

    val rank : ('a, 'b) t -> 'a -> int option

    val to_tree : ('a, 'b) t -> ('a, 'b) tree

    val to_sequence : ?order:[ `Decreasing_key | `Increasing_key ] ->
           ?keys_greater_or_equal_to:'a ->
           ?keys_less_or_equal_to:'a ->
           ('a, 'b) t -> ('a * 'b) Sequence.t