package monads

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package monads
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include Core_kernel.Hashtbl_intf.S with type ('a, 'b) hashtbl = ('a, 'b) Core_kernel.Hashtbl.t with type key = t
include Core_kernel.Hashtbl_intf.S_plain with type ('a, 'b) hashtbl = ('a, 'b) Core_kernel.Hashtbl.t with type key = t
type key = t
type ('a, 'b) hashtbl = ('a, 'b) Core_kernel.Hashtbl.t
type 'b t = (key, 'b) hashtbl
val sexp_of_t : ('b -> Ppx_sexp_conv_lib.Sexp.t) -> 'b t -> Ppx_sexp_conv_lib.Sexp.t
type ('a, 'b) t_ = 'b t
type 'a key_ = key
val hashable : key Base.Hashable.t
include Base.Invariant.S1 with type 'b t := 'b t
val invariant : ('a -> unit) -> 'a t -> unit
val create : ('a key_, 'b, unit -> ('a, 'b) t_) Core_kernel.Hashtbl_intf.create_options_without_hashable
val of_alist : ('a key_, 'b, ('a key_ * 'b) list -> [ `Duplicate_key of 'a key_ | `Ok of ('a, 'b) t_ ]) Core_kernel.Hashtbl_intf.create_options_without_hashable
val of_alist_report_all_dups : ('a key_, 'b, ('a key_ * 'b) list -> [ `Duplicate_keys of 'a key_ list | `Ok of ('a, 'b) t_ ]) Core_kernel.Hashtbl_intf.create_options_without_hashable
val of_alist_or_error : ('a key_, 'b, ('a key_ * 'b) list -> ('a, 'b) t_ Base.Or_error.t) Core_kernel.Hashtbl_intf.create_options_without_hashable
val of_alist_exn : ('a key_, 'b, ('a key_ * 'b) list -> ('a, 'b) t_) Core_kernel.Hashtbl_intf.create_options_without_hashable
val of_alist_multi : ('a key_, 'b list, ('a key_ * 'b) list -> ('a, 'b list) t_) Core_kernel.Hashtbl_intf.create_options_without_hashable
val create_mapped : ('a key_, 'b, get_key:('r -> 'a key_) -> get_data:('r -> 'b) -> 'r list -> [ `Duplicate_keys of 'a key_ list | `Ok of ('a, 'b) t_ ]) Core_kernel.Hashtbl_intf.create_options_without_hashable
val create_with_key : ('a key_, 'r, get_key:('r -> 'a key_) -> 'r list -> [ `Duplicate_keys of 'a key_ list | `Ok of ('a, 'r) t_ ]) Core_kernel.Hashtbl_intf.create_options_without_hashable
val create_with_key_or_error : ('a key_, 'r, get_key:('r -> 'a key_) -> 'r list -> ('a, 'r) t_ Base.Or_error.t) Core_kernel.Hashtbl_intf.create_options_without_hashable
val create_with_key_exn : ('a key_, 'r, get_key:('r -> 'a key_) -> 'r list -> ('a, 'r) t_) Core_kernel.Hashtbl_intf.create_options_without_hashable
val group : ('a key_, 'b, get_key:('r -> 'a key_) -> get_data:('r -> 'b) -> combine:('b -> 'b -> 'b) -> 'r list -> ('a, 'b) t_) Core_kernel.Hashtbl_intf.create_options_without_hashable
include Core_kernel.Hashtbl_intf.Accessors with type ('a, 'b) t := ('a, 'b) t_ with type 'a key := 'a key_

Accessors

val sexp_of_key : ('a, _) t_ -> 'a key_ -> Base.Sexp.t
val clear : (_, _) t_ -> unit
val copy : ('a, 'b) t_ -> ('a, 'b) t_
val fold : ('a, 'b) t_ -> init:'c -> f:(key:'a key_ -> data:'b -> 'c -> 'c) -> 'c

Attempting to modify (set, remove, etc.) the hashtable during iteration (fold, iter, iter_keys, iteri) will raise an exception.

val iter_keys : ('a, _) t_ -> f:('a key_ -> unit) -> unit
val iter : (_, 'b) t_ -> f:('b -> unit) -> unit
val iteri : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> unit) -> unit

Iterates over both keys and values.

Example:

      let h = Hashtbl.of_alist_exn (module Int) [(1, 4); (5, 6)] in
      Hashtbl.iteri h ~f:(fun ~key ~data ->
        print_endline (Printf.sprintf "%d-%d" key data));;
      1-4
      5-6
      - : unit = ()
val existsi : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> bool) -> bool
val exists : (_, 'b) t_ -> f:('b -> bool) -> bool
val for_alli : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> bool) -> bool
val for_all : (_, 'b) t_ -> f:('b -> bool) -> bool
val counti : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> bool) -> int
val count : (_, 'b) t_ -> f:('b -> bool) -> int
val length : (_, _) t_ -> int
val is_empty : (_, _) t_ -> bool
val mem : ('a, _) t_ -> 'a key_ -> bool
val remove : ('a, _) t_ -> 'a key_ -> unit
val set : ('a, 'b) t_ -> key:'a key_ -> data:'b -> unit

Sets the given key to data.

val add : ('a, 'b) t_ -> key:'a key_ -> data:'b -> [ `Ok | `Duplicate ]

add and add_exn leave the table unchanged if the key was already present.

val add_exn : ('a, 'b) t_ -> key:'a key_ -> data:'b -> unit
val change : ('a, 'b) t_ -> 'a key_ -> f:('b option -> 'b option) -> unit

change t key ~f changes t's value for key to be f (find t key).

val update : ('a, 'b) t_ -> 'a key_ -> f:('b option -> 'b) -> unit

update t key ~f is change t key ~f:(fun o -> Some (f o)).

val map : ('a, 'b) t_ -> f:('b -> 'c) -> ('a, 'c) t_

map t f returns a new table with values replaced by the result of applying f to the current values.

Example:

      let h = Hashtbl.of_alist_exn (module Int) [(1, 4); (5, 6)] in
      let h' = Hashtbl.map h ~f:(fun x -> x * 2) in
      Hashtbl.to_alist h';;
      - : (int * int) list = [(5, 12); (1, 8)]
val mapi : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> 'c) -> ('a, 'c) t_

Like map, but the function f takes both key and data as arguments.

val filter_map : ('a, 'b) t_ -> f:('b -> 'c option) -> ('a, 'c) t_

Returns a new table by filtering the given table's values by f: the keys for which f applied to the current value returns Some are kept, and those for which it returns None are discarded.

Example:

      let h = Hashtbl.of_alist_exn (module Int) [(1, 4); (5, 6)] in
      Hashtbl.filter_map h ~f:(fun x -> if x > 5 then Some x else None)
      |> Hashtbl.to_alist;;
      - : (int * int) list = [(5, 6)]
val filter_mapi : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> 'c option) -> ('a, 'c) t_

Like filter_map, but the function f takes both key and data as arguments.

val filter_keys : ('a, 'b) t_ -> f:('a key_ -> bool) -> ('a, 'b) t_
val filter : ('a, 'b) t_ -> f:('b -> bool) -> ('a, 'b) t_
val filteri : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> bool) -> ('a, 'b) t_
val partition_map : ('a, 'b) t_ -> f:('b -> [ `Fst of 'c | `Snd of 'd ]) -> ('a, 'c) t_ * ('a, 'd) t_

Returns new tables with bound values partitioned by f applied to the bound values.

val partition_mapi : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> [ `Fst of 'c | `Snd of 'd ]) -> ('a, 'c) t_ * ('a, 'd) t_

Like partition_map, but the function f takes both key and data as arguments.

val partition_tf : ('a, 'b) t_ -> f:('b -> bool) -> ('a, 'b) t_ * ('a, 'b) t_

Returns a pair of tables (t1, t2), where t1 contains all the elements of the initial table which satisfy the predicate f, and t2 contains the rest.

val partitioni_tf : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> bool) -> ('a, 'b) t_ * ('a, 'b) t_

Like partition_tf, but the function f takes both key and data as arguments.

val find_or_add : ('a, 'b) t_ -> 'a key_ -> default:(unit -> 'b) -> 'b

find_or_add t k ~default returns the data associated with key k if it is in the table t, and otherwise assigns k the value returned by default ().

val findi_or_add : ('a, 'b) t_ -> 'a key_ -> default:('a key_ -> 'b) -> 'b

Like find_or_add but default takes the key as an argument.

val find : ('a, 'b) t_ -> 'a key_ -> 'b option

find t k returns Some (the current binding) of k in t, or None if no such binding exists.

val find_exn : ('a, 'b) t_ -> 'a key_ -> 'b

find_exn t k returns the current binding of k in t, or raises Caml.Not_found or Not_found_s if no such binding exists.

val find_and_call : ('a, 'b) t_ -> 'a key_ -> if_found:('b -> 'c) -> if_not_found:('a key_ -> 'c) -> 'c

find_and_call t k ~if_found ~if_not_found

is equivalent to:

match find t k with Some v -> if_found v | None -> if_not_found k

except that it doesn't allocate the option.

val findi_and_call : ('a, 'b) t_ -> 'a key_ -> if_found:(key:'a key_ -> data:'b -> 'c) -> if_not_found:('a key_ -> 'c) -> 'c
val find_and_remove : ('a, 'b) t_ -> 'a key_ -> 'b option

find_and_remove t k returns Some (the current binding) of k in t and removes it, or None is no such binding exists.

val merge : ('k, 'a) t_ -> ('k, 'b) t_ -> f: (key:'k key_ -> [ `Left of 'a | `Right of 'b | `Both of 'a * 'b ] -> 'c option) -> ('k, 'c) t_

Merges two hashtables.

The result of merge f h1 h2 has as keys the set of all k in the union of the sets of keys of h1 and h2 for which d(k) is not None, where:

d(k) =

  • f ~key:k (Some d1) None if k in h1 maps to d1, and h2 does not have data for k;
  • f ~key:k None (Some d2) if k in h2 maps to d2, and h1 does not have data for k;
  • f ~key:k (Some d1) (Some d2) otherwise, where k in h1 maps to d1 and k in h2 maps to d2.

Each key k is mapped to a single piece of data x, where d(k) = Some x.

Example:

      let h1 = Hashtbl.of_alist_exn (module Int) [(1, 5); (2, 3232)] in
      let h2 = Hashtbl.of_alist_exn (module Int) [(1, 3)] in
      Hashtbl.merge h1 h2 ~f:(fun ~key:_ -> function
        | `Left x -> Some (`Left x)
        | `Right x -> Some (`Right x)
        | `Both (x, y) -> if x=y then None else Some (`Both (x,y))
      ) |> Hashtbl.to_alist;;
      - : (int * [> `Both of int * int | `Left of int | `Right of int ]) list =
      [(2, `Left 3232); (1, `Both (5, 3))]
type 'a merge_into_action =
  1. | Remove
  2. | Set_to of 'a

Every key in src will be removed or set in dst according to the return value of f.

val merge_into : src:('k, 'a) t_ -> dst:('k, 'b) t_ -> f:(key:'k key_ -> 'a -> 'b option -> 'b merge_into_action) -> unit
val keys : ('a, _) t_ -> 'a key_ list

Returns the list of all keys for given hashtable.

val data : (_, 'b) t_ -> 'b list

Returns the list of all data for given hashtable.

val filter_keys_inplace : ('a, _) t_ -> f:('a key_ -> bool) -> unit

filter_inplace t ~f removes all the elements from t that don't satisfy f.

val filter_inplace : (_, 'b) t_ -> f:('b -> bool) -> unit
val filteri_inplace : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> bool) -> unit
val map_inplace : (_, 'b) t_ -> f:('b -> 'b) -> unit

map_inplace t ~f applies f to all elements in t, transforming them in place.

val mapi_inplace : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> 'b) -> unit
val filter_map_inplace : (_, 'b) t_ -> f:('b -> 'b option) -> unit

filter_map_inplace combines the effects of map_inplace and filter_inplace.

val filter_mapi_inplace : ('a, 'b) t_ -> f:(key:'a key_ -> data:'b -> 'b option) -> unit
val equal : ('a, 'b) t_ -> ('a, 'b) t_ -> ('b -> 'b -> bool) -> bool

equal t1 t2 f and similar t1 t2 f both return true iff t1 and t2 have the same keys and for all keys k, f (find_exn t1 k) (find_exn t2 k). equal and similar only differ in their types.

val similar : ('a, 'b1) t_ -> ('a, 'b2) t_ -> ('b1 -> 'b2 -> bool) -> bool
val to_alist : ('a, 'b) t_ -> ('a key_ * 'b) list

Returns the list of all (key, data) pairs for given hashtable.

val validate : name:('a key_ -> string) -> 'b Base.Validate.check -> ('a, 'b) t_ Base.Validate.check
val incr : ?by:int -> ?remove_if_zero:bool -> ('a, int) t_ -> 'a key_ -> unit

remove_if_zero's default is false.

val decr : ?by:int -> ?remove_if_zero:bool -> ('a, int) t_ -> 'a key_ -> unit
include Core_kernel.Hashtbl_intf.Multi with type ('a, 'b) t := ('a, 'b) t_ with type 'a key := 'a key_
val add_multi : ('a, 'b list) t_ -> key:'a key_ -> data:'b -> unit

add_multi t ~key ~data if key is present in the table then cons data on the list, otherwise add key with a single element list.

val remove_multi : ('a, _ list) t_ -> 'a key_ -> unit

remove_multi t key updates the table, removing the head of the list bound to key. If the list has only one element (or is empty) then the binding is removed.

val find_multi : ('a, 'b list) t_ -> 'a key_ -> 'b list

find_multi t key returns the empty list if key is not present in the table, returns t's values for key otherwise.

module Provide_of_sexp (Key : sig ... end) : sig ... end
module Provide_bin_io (Key : sig ... end) : sig ... end
include sig ... end
val t_of_sexp : (Ppx_sexp_conv_lib.Sexp.t -> 'v_x__002_) -> Ppx_sexp_conv_lib.Sexp.t -> 'v_x__002_ t
include Core_kernel.Hashtbl_intf.Binable.S1 with type 'v t := 'v t
val bin_shape_t : Bin_prot.Shape.t -> Bin_prot.Shape.t
val bin_size_t : ('a, 'a t) Bin_prot.Size.sizer1
val bin_write_t : ('a, 'a t) Bin_prot.Write.writer1
val bin_read_t : ('a, 'a t) Bin_prot.Read.reader1
val __bin_read_t__ : ('a, int -> 'a t) Bin_prot.Read.reader1
val bin_writer_t : ('a, 'a t) Bin_prot.Type_class.S1.writer
val bin_reader_t : ('a, 'a t) Bin_prot.Type_class.S1.reader
val bin_t : ('a, 'a t) Bin_prot.Type_class.S1.t
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