ocaml-containers/core/CCMultiMap.mli

(*
copyright (c) 2013, simon cruanes
all rights reserved.

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*)

(** {1 Multimap} *)

type 'a sequence = ('a -> unit) -> unit

module type S = sig
  type key
  type value
  type t

  val empty : t
    (** Empty multimap *)

  val is_empty : t -> bool
    (** Empty multimap? *)

  val add : t -> key -> value -> t
    (** Add a key/value binding *)

  val remove : t -> key -> value -> t
    (** Remove the binding *)

  val remove_all : t -> key -> t
    (** Remove the key from the map *)

  val mem : t -> key -> bool
    (** Is there a binding for this key? *)

  val find : t -> key -> value list
    (** List of values for this key *)

  val find_iter : t -> key -> (value -> unit) -> unit
    (** Iterate on bindings for this key *)

  val count : t -> key -> int
    (** Number of bindings for this key *)

  val iter : t -> (key -> value -> unit) -> unit
    (** Iterate on all key/value *)

  val fold : t -> 'a -> ('a -> key -> value -> 'a) -> 'a
    (** Fold on all key/value *)

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

  val union : t -> t -> t
    (** Union of multimaps *)

  val inter : t -> t -> t
    (** Intersection of multimaps *)

  val diff : t -> t -> t
    (** Difference of maps, ie bindings of the first that are not
        in the second *)

  val equal : t -> t -> bool
    (** Same multimap *)

  val compare : t -> t -> int
    (** Total order on multimaps *)

  val submap : t -> t -> bool
    (** [submap m1 m2] is true iff all bindings of [m1] are also in [m2] *)

  val to_seq : t -> (key * value) sequence

  val of_seq : ?init:t -> (key * value) sequence -> t

  val keys : t -> key sequence

  val values : t -> value sequence
    (** Some values may occur several times *)
end

module type OrderedType = sig
  type t
  val compare : t -> t -> int
end

module Make(K : OrderedType)(V : OrderedType) : S with type key = K.t and type value = V.t

(** {2 Two-Way Multimap}
Represents n-to-n mappings between two types. Each element from the "left"
is mapped to several right values, and conversely.

@since NEXT_RELEASE *)

module type BIDIR = sig
  type t
  type left
  type right

  val empty : t

  val is_empty : t -> bool

  val add : t -> left -> right -> t
  (** Add a binding (left,right) *)

  val remove : t -> left -> right -> t
  (** Remove a specific binding *)

  val cardinal_left : t -> int
  (** number of distinct left keys *)

  val cardinal_right : t -> int
  (** number of distinct right keys *)

  val remove_left : t -> left -> t
  (** Remove all bindings for the left key *)

  val remove_right : t -> right -> t
  (** Remove all bindings for the right key *)

  val mem_left : t -> left -> bool
  (** Is the left key present in at least one pair? *)

  val mem_right : t -> right -> bool
  (** Is the right key present in at least one pair? *)

  val find_left : t -> left -> right sequence
  (** Find all bindings for this given left-key *)

  val find_right : t -> right -> left sequence
  (** Find all bindings for this given right-key *)

  val find1_left : t -> left -> right option
  (** like {!find_left} but returns at most one value *)

  val find1_right : t -> right -> left option
  (** like {!find_right} but returns at most one value *)

  val fold : ('a -> left -> right -> 'a) -> 'a -> t -> 'a
  (** Fold on pairs *)

  val pairs : t -> (left * right) sequence
  (** Iterate on pairs *)

  val add_pairs : t -> (left * right) sequence -> t
  (** Add pairs *)

  val seq_left : t -> left sequence
  val seq_right : t -> right sequence
end

module MakeBidir(L : OrderedType)(R : OrderedType) : BIDIR
  with type left = L.t and type right = R.t