Module Base.Hashtbl

val hash : 'a ‑> int
val hash_param : int ‑> int ‑> 'a ‑> int
type ('a, 'b) t

We use [@@deriving_inline sexp_of][@@@end] but not [@@deriving sexp] because we want people to be explicit about the hash and comparison functions used when creating hashtables. One can use Hashtbl.Poly.t, which does have [@@deriving_inline sexp][@@@end], to use polymorphic comparison and hashing.

include sig ... end
val sexp_of_t : ('a ‑> Base__.Sexplib.Sexp.t) ‑> ('b ‑> Base__.Sexplib.Sexp.t) ‑> ('a, 'b) t ‑> Base__.Sexplib.Sexp.t
include Invariant.S2 with type (a, b) t := (a, b) t
type ('a, 'b) t
include Hashtbl_intf.Creators with type (a, b) t := (a, b) t with type 'a key = 'a with type (a, b, z) create_options := (a, b, z) Hashtbl_intf.create_options_with_first_class_module
type ('a, 'b) t
type 'a key = 'a
type ('key, 'data, 'z) create_options
val create : ('a key, 'b, unit ‑> ('a, 'b) t) create_options
val of_alist : ('a key, 'b, ('a key * 'b) list ‑> [ `Ok of ('a, 'b) t | `Duplicate_key of 'a key ]) create_options
val of_alist_report_all_dups : ('a key, 'b, ('a key * 'b) list ‑> [ `Ok of ('a, 'b) t | `Duplicate_keys of 'a key list ]) create_options
val of_alist_or_error : ('a key, 'b, ('a key * 'b) list ‑> ('a, 'b) t Or_error.t) create_options
val of_alist_exn : ('a key, 'b, ('a key * 'b) list ‑> ('a, 'b) t) create_options
val of_alist_multi : ('a key, 'b list, ('a key * 'b) list ‑> ('a, 'b list) t) create_options
val create_mapped : ('a key, 'b, get_key:('r ‑> 'a key) ‑> get_data:('r ‑> 'b) ‑> 'r list ‑> [ `Ok of ('a, 'b) t | `Duplicate_keys of 'a key list ]) create_options
 create_mapped get_key get_data [x1,...,xn]
         = of_alist [get_key x1, get_data x1; ...; get_key xn, get_data xn]
val create_with_key : ('a key, 'r, get_key:('r ‑> 'a key) ‑> 'r list ‑> [ `Ok of ('a, 'r) t | `Duplicate_keys of 'a key list ]) create_options
 create_with_key ~get_key [x1,...,xn]
         = of_alist [get_key x1, x1; ...; get_key xn, xn]
val create_with_key_or_error : ('a key, 'r, get_key:('r ‑> 'a key) ‑> 'r list ‑> ('a, 'r) t Or_error.t) create_options
val create_with_key_exn : ('a key, 'r, get_key:('r ‑> 'a key) ‑> 'r list ‑> ('a, 'r) t) create_options
val group : ('a key, 'b, get_key:('r ‑> 'a key) ‑> get_data:('r ‑> 'b) ‑> combine:('b ‑> 'b ‑> 'b) ‑> 'r list ‑> ('a, 'b) t) create_options
include Hashtbl_intf.Accessors with type (a, b) t := (a, b) t with type a key := a key
type ('a, 'b) t
type 'a key
val sexp_of_key : ('a, _) t ‑> 'a key ‑> 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
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
val iter_vals : (_, 'b) t ‑> f:('b ‑> unit) ‑> 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 replace : ('a, 'b) t ‑> key:'a key ‑> data:'b ‑> unit
val set : ('a, 'b) t ‑> key:'a key ‑> data:'b ‑> unit
val add : ('a, 'b) t ‑> key:'a key ‑> data:'b ‑> [ `Ok | `Duplicate ]
val add_or_error : ('a, 'b) t ‑> key:'a key ‑> data:'b ‑> unit Or_error.t
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 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 map : ('a, 'b) t ‑> f:('b ‑> 'c) ‑> ('a, 'c) t

map t f returns new table with bound values replaced by f applied to the bound values

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

like map, but function takes both key and data as arguments

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

returns new map with bound values filtered by f applied to the bound values

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

like filter_map, but function 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 maps 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 function takes both key and data as arguments

val partition_tf : ('a, 'b) t ‑> f:('b ‑> bool) ‑> ('a, 'b) t * ('a, 'b) t
val partitioni_tf : ('a, 'b) t ‑> f:(key:'a key ‑> data:'b ‑> bool) ‑> ('a, 'b) t * ('a, 'b) t
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, otherwise it lets d = default() and adds it to the table.

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 Not_found 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 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

Merge 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 is to d1, and h2 does not map k;
  • f ~key:k None (Some d2) if k in h2 is to d2, and h1 does not map k;
  • f ~key:k (Some d1) (Some d2) otherwise, where k in h1 is to d1 and k in h2 is to d2.

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

type 'a merge_into_action =
| Remove
| 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 replace_all : (_, 'b) t ‑> f:('b ‑> 'b) ‑> unit
val replace_alli : ('a, 'b) t ‑> f:(key:'a key ‑> data:'b ‑> 'b) ‑> unit
val filter_replace_all : (_, 'b) t ‑> f:('b ‑> 'b option) ‑> unit
val filter_replace_alli : ('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 Validate.check ‑> ('a, 'b) t 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
val hashable : ('key, _) t ‑> 'key Hashable.t
module Using_hashable : Hashtbl_intf.S_using_hashable with type ('a, 'b) t = ('a, 'b) t with type a key := a key with type 'a merge_into_action = 'a merge_into_action
module Creators : functor (Key : sig ... end) -> sig ... end
module Poly : Hashtbl_intf.S_poly with type ('a, 'b) t = ('a, 'b) t
module M : functor (K : T.T) -> sig ... end

M is meant to be used in combination with OCaml applicative functor types:

module type Sexp_of_m : sig ... end
module type M_of_sexp : sig ... end
val sexp_of_m__t : (module Sexp_of_m with type t = 'k) ‑> ('v ‑> Sexp.t) ‑> ('k, 'v) t ‑> Sexp.t
val m__t_of_sexp : (module M_of_sexp with type t = 'k) ‑> (Sexp.t ‑> 'v) ‑> Sexp.t ‑> ('k, 'v) t