mirror of
https://github.com/c-cube/ocaml-containers.git
synced 2025-12-09 04:35:29 -05:00
133 lines
3.5 KiB
OCaml
133 lines
3.5 KiB
OCaml
|
|
(* This file is free software, part of containers. See file "license" for more details. *)
|
|
|
|
(** {1 Hash combinators} *)
|
|
|
|
(** {2 Definitions} *)
|
|
|
|
type t = int
|
|
(** A hash value is a positive integer *)
|
|
|
|
type state
|
|
(** State required by the hash function.
|
|
@since NEXT_RELEASE the state is abstract, for more flexibility *)
|
|
|
|
type 'a hash_fun = 'a -> state -> state
|
|
(** Hash function for values of type ['a], merging a fingerprint of the
|
|
value into the state of type [t] *)
|
|
|
|
(** {2 Applying Hash} *)
|
|
|
|
val init : state
|
|
(** Initial value *)
|
|
|
|
val finish : state -> int
|
|
(** Extract a usable hash value *)
|
|
|
|
val apply : 'a hash_fun -> 'a -> int
|
|
(** Apply a hash function to a value.
|
|
[apply f x] is the same as [finish (f x init)] *)
|
|
|
|
(** {2 Basic Combinators}
|
|
|
|
Those combinators have been renamed in 0.13, so as to
|
|
remove the trailing "_".
|
|
They are now defined by the application of {!Make}
|
|
|
|
*)
|
|
|
|
val bool_ : bool hash_fun
|
|
(** @deprecated use {!bool} *)
|
|
|
|
val char_ : char hash_fun
|
|
(** @deprecated use {!char} *)
|
|
|
|
val int_ : int hash_fun
|
|
(** @deprecated use {!int} *)
|
|
|
|
val string_ : string hash_fun
|
|
(** @deprecated use {!string} *)
|
|
|
|
val int32_ : int32 hash_fun
|
|
(** @deprecated use {!int32} *)
|
|
|
|
val int64_ : int64 hash_fun
|
|
(** @deprecated use {!int64} *)
|
|
|
|
val nativeint_ : nativeint hash_fun
|
|
(** @deprecated use {!nativeint} *)
|
|
|
|
val list_ : 'a hash_fun -> 'a list hash_fun
|
|
(** Hash a list. Each element is hashed using [f].
|
|
@deprecated use {!list} *)
|
|
|
|
val array_ : 'a hash_fun -> 'a array hash_fun
|
|
(** @deprecated use {!array} *)
|
|
|
|
val opt : 'a hash_fun -> 'a option hash_fun
|
|
val pair : 'a hash_fun -> 'b hash_fun -> ('a * 'b) hash_fun
|
|
val triple : 'a hash_fun -> 'b hash_fun -> 'c hash_fun -> ('a * 'b * 'c) hash_fun
|
|
|
|
val if_ : bool -> 'a hash_fun -> 'a hash_fun -> 'a hash_fun
|
|
(** Decide which hash function to use depending on the boolean *)
|
|
|
|
(** {2 Iterators} *)
|
|
|
|
type 'a sequence = ('a -> unit) -> unit
|
|
type 'a gen = unit -> 'a option
|
|
type 'a klist = unit -> [`Nil | `Cons of 'a * 'a klist]
|
|
|
|
val seq : 'a hash_fun -> 'a sequence hash_fun
|
|
val gen : 'a hash_fun -> 'a gen hash_fun
|
|
val klist : 'a hash_fun -> 'a klist hash_fun
|
|
|
|
(** {2 Generic Hashing}
|
|
|
|
Parametrize over the state, and some primitives to hash basic types.
|
|
This can for instance be used for cryptographic hashing or
|
|
checksums such as MD5.
|
|
|
|
@since 0.13 *)
|
|
|
|
module type HASH = sig
|
|
type state
|
|
|
|
val int : int -> state -> state
|
|
val bool : bool -> state -> state
|
|
val char : char -> state -> state
|
|
val int32 : int32 -> state -> state
|
|
val int64 : int64 -> state -> state
|
|
val nativeint : nativeint -> state -> state
|
|
val slice : string -> int -> int -> state -> state
|
|
(** [slice s i len state] hashes the slice [i, ... i+len-1] of [s]
|
|
into [state] *)
|
|
end
|
|
|
|
module type S = sig
|
|
include HASH
|
|
|
|
type 'a hash_fun = 'a -> state -> state
|
|
|
|
val string : string hash_fun
|
|
|
|
val list : 'a hash_fun -> 'a list hash_fun
|
|
|
|
val array : 'a hash_fun -> 'a array hash_fun
|
|
|
|
val opt : 'a hash_fun -> 'a option hash_fun
|
|
val pair : 'a hash_fun -> 'b hash_fun -> ('a * 'b) hash_fun
|
|
val triple : 'a hash_fun -> 'b hash_fun -> 'c hash_fun -> ('a * 'b * 'c) hash_fun
|
|
|
|
val if_ : bool -> 'a hash_fun -> 'a hash_fun -> 'a hash_fun
|
|
(** Decide which hash function to use depending on the boolean *)
|
|
|
|
(** {2 Iterators} *)
|
|
|
|
val seq : 'a hash_fun -> 'a sequence hash_fun
|
|
val gen : 'a hash_fun -> 'a gen hash_fun
|
|
val klist : 'a hash_fun -> 'a klist hash_fun
|
|
end
|
|
|
|
module Make(H : HASH) : S with type state = H.state
|
|
|
|
include S with type state := state and type 'a hash_fun := 'a hash_fun
|