(*
Copyright (c) 2013, Simon Cruanes
All rights reserved.

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modification, are permitted provided that the following conditions are met:

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*)

(** {1 Small set structure} *)

(** This set structure is polymorphic, using a user-provided comparison
    function. It is implemented as a sorted list, so most operations
    are in linear time. *)

type 'a t
  (** Set of elements of type 'a *)

val empty : cmp:('a -> 'a -> int) -> 'a t
  (** Create an empty set *)

val is_empty : _ t -> bool
  (** Is the set empty? *)

val mem : 'a t -> 'a -> bool
  (** Is the element member of the set? *)

val add : 'a t -> 'a -> 'a t
  (** add an element *)

val remove : 'a t -> 'a -> 'a t
  (** Remove element *)

val choose : 'a t -> 'a
  (** Some element of the set, of Not_found *)

val fold : ('a -> 'b -> 'a) -> 'a -> 'b t -> 'a
  (** Fold on elements *)

val iter : ('a -> unit) -> 'a t -> unit
  (** Iterate on elements *)

val size : _ t -> int
  (** Number of elements *)

val to_seq : 'a t -> 'a Sequence.t

val of_seq : 'a t -> 'a Sequence.t -> 'a t

val to_list : 'a t -> 'a list

val of_list : 'a t -> 'a list -> 'a t