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Module Bounded_int_table

module Bounded_int_table: sig .. end
A Bounded_int_table is a table whose keys can be mapped to integers in a fixed range, 0 ... num_keys-1, where num_keys is specified at table-creation time. The purpose of Bounded_int_table is to be faster than Hashtbl in situations where one is willing to pay a space cost for the speed.

Bounded_int_table presents a subset of the Hashtbl interface. The key type can be any type, but table creation requires a key_to_int function, which will be used to extract the integer of all keys. If multiple keys map to the same integer, then only one of them can be in the table at a time. Any operation that supplies a key whose corresponding integer is outside the allowed range for the table will cause an exception.

A Bounded_int_table is implemented using two fixed size arrays of size num_keys, which is supplied at table-creation time. The space used does not depend on the length of the table but rather only on num_keys. Operations that deal with a single element (find, mem, add, remove, set) take constant time, and perform one or two array operations. Operations that deal with all of the keys defined in the table (data, fold, iter, iter_vals, keys, to_alist) take time proportional to the length of the table, not num_keys.

type ('key, 'data) t 
type ('a, 'b) table = ('a, 'b) t 
include Equal.S2
val invariant : ('a, 'b) t -> unit
val create : ?sexp_of_key:('key -> Std_internal.Sexp.t) ->
       num_keys:int ->
       key_to_int:('key -> int) -> unit -> ('key, 'data) t
create ~num_keys ~key_to_int returns a table where the keys can map to 0 .. num_keys-1, according to key_to_int. It is an error if num_keys < 0.

sexp_of_key, if supplied, will be used to display keys in error messages.

val keys : ('key, 'a) t -> 'key list
Standard hashtbl functions.
val data : ('a, 'data) t -> 'data list
val find : ('key, 'data) t -> 'key -> 'data option
val find_exn : ('key, 'data) t -> 'key -> 'data
val find_or_add : ('key, 'data) t -> 'key -> default:(unit -> 'data) -> 'data
val fold : ('key, 'data) t ->
       init:'accum -> f:(key:'key -> data:'data -> 'accum -> 'accum) -> 'accum
val iter : ('key, 'data) t ->
       f:(key:'key -> data:'data -> unit) -> unit
val iter_vals : ('a, 'data) t -> f:('data -> unit) -> unit
val filter_mapi : ('key, 'data1) t ->
       f:(key:'key -> data:'data1 -> 'data2 option) ->
       ('key, 'data2) t
val filter_map : ('key, 'data1) t ->
       f:('data1 -> 'data2 option) -> ('key, 'data2) t
val mapi : ('key, 'data1) t ->
       f:(key:'key -> data:'data1 -> 'data2) -> ('key, 'data2) t
val map : ('key, 'data1) t ->
       f:('data1 -> 'data2) -> ('key, 'data2) t
val for_alli : ('key, 'data) t ->
       f:(key:'key -> data:'data -> bool) -> bool
val existsi : ('key, 'data) t ->
       f:(key:'key -> data:'data -> bool) -> bool
val for_all : ('a, 'data) t -> f:('data -> bool) -> bool
val exists : ('a, 'data) t -> f:('data -> bool) -> bool
val length : ('a, 'b) t -> int
val mem : ('key, 'a) t -> 'key -> bool
val remove : ('key, 'a) t -> 'key -> unit
val set : ('a, 'b) t -> key:'a -> data:'b -> unit
val add : ('a, 'b) t ->
       key:'a -> data:'b -> [ `Duplicate of 'b | `Ok ]
val add_exn : ('a, 'b) t -> key:'a -> data:'b -> unit
val to_alist : ('key, 'data) t -> ('key * 'data) list
module With_key: 
functor (Key : sig
type t 



val to_int : t -> int
val t_of_sexp : Sexplib.Sexp.t -> t
val sexp_of_t : t -> Sexplib.Sexp.t
val bin_t : t Bin_prot.Type_class.t
val bin_read_t : t Bin_prot.Read_ml.reader
val bin_read_t_ : t Bin_prot.Unsafe_read_c.reader
val bin_read_t__ : (int -> t) Bin_prot.Unsafe_read_c.reader
val bin_reader_t : t Bin_prot.Type_class.reader
val bin_size_t : t Bin_prot.Size.sizer
val bin_write_t : t Bin_prot.Write_ml.writer
val bin_write_t_ : t Bin_prot.Unsafe_write_c.writer
val bin_writer_t : t Bin_prot.Type_class.writer
end) -> sig .. end
val debug : bool Pervasives.ref
set debug := true to turn on debugging, including potentially slow invariant checking.
val sexp_of_t : ('key -> Sexplib.Sexp.t) ->
       ('data -> Sexplib.Sexp.t) ->
       ('key, 'data) t -> Sexplib.Sexp.t

create ~num_keys ~key_to_int returns a table where the keys can map to 0 .. num_keys-1, according to key_to_int. It is an error if num_keys < 0.

sexp_of_key, if supplied, will be used to display keys in error messages.

Standard hashtbl functions.

Serialization of a bounded int table using bin_io or sexp preserves num_keys, but only takes space proportional to the length of the table.

set debug := true to turn on debugging, including potentially slow invariant checking.