You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

48 lines
834 B

(*
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*)
open! Core
module type NormalizedT = sig
include Caml.Hashtbl.HashedType
val normalize : t -> t
end
module type S = sig
type t
val normalize : t -> t
val reset : unit -> unit
end
module Make (T : NormalizedT) = struct
type t = T.t
module H = Caml.Hashtbl.Make (T)
let table : t H.t = H.create 11
let normalize t =
match H.find_opt table t with
| Some t' ->
t'
| None ->
let normalized = T.normalize t in
H.add table normalized normalized ;
normalized
let reset () = H.reset table
end
module StringNormalizer = Make (struct
include String
let normalize = Fn.id
end)