type keyand +'a t
val empty : 'a tval is_empty : 'a t -> boolval mem : key -> 'a t -> boolval add : key:key -> data:'a -> 'a t -> 'a tval update : key:key -> f:('a option -> 'a option) -> 'a t -> 'a tval singleton : key -> 'a -> 'a tval remove : key -> 'a t -> 'a tval merge : f:(key -> 'a option -> 'b option -> 'c option) -> 'a t -> 'b t -> 'c tval union : f:(key -> 'a -> 'a -> 'a option) -> 'a t -> 'a t -> 'a tval compare : cmp:('a -> 'a -> int) -> 'a t -> 'a t -> intval equal : cmp:('a -> 'a -> bool) -> 'a t -> 'a t -> boolval iter : f:(key:key -> data:'a -> unit) -> 'a t -> unitval fold : f:(key:key -> data:'a -> 'b -> 'b) -> 'a t -> init:'b -> 'bval for_all : f:(key -> 'a -> bool) -> 'a t -> boolval exists : f:(key -> 'a -> bool) -> 'a t -> boolval filter : f:(key -> 'a -> bool) -> 'a t -> 'a tval partition : f:(key -> 'a -> bool) -> 'a t -> 'a t * 'a tval cardinal : 'a t -> intval bindings : 'a t -> (key * 'a) listval min_binding : 'a t -> key * 'aval min_binding_opt : 'a t -> (key * 'a) optionval max_binding : 'a t -> key * 'aval max_binding_opt : 'a t -> (key * 'a) optionval choose : 'a t -> key * 'aval choose_opt : 'a t -> (key * 'a) optionval split : key -> 'a t -> 'a t * 'a option * 'a tval find : key -> 'a t -> 'aval find_opt : key -> 'a t -> 'a optionval find_first : f:(key -> bool) -> 'a t -> key * 'aval find_first_opt : f:(key -> bool) -> 'a t -> (key * 'a) optionval find_last : f:(key -> bool) -> 'a t -> key * 'aval find_last_opt : f:(key -> bool) -> 'a t -> (key * 'a) optionval map : f:('a -> 'b) -> 'a t -> 'b tval mapi : f:(key -> 'a -> 'b) -> 'a t -> 'b tval to_seq : 'a t -> (key * 'a) Seq.tval to_seq_from : key -> 'a t -> (key * 'a) Seq.tval add_seq : (key * 'a) Seq.t -> 'a t -> 'a tval of_seq : (key * 'a) Seq.t -> 'a t