(************************************************************************)
(*         *   The Coq Proof Assistant / The Coq Development Team       *)
(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2018       *)
(* <O___,, *       (see CREDITS file for the list of authors)           *)
(*   \VV/  **************************************************************)
(*    //   *    This file is distributed under the terms of the         *)
(*         *     GNU Lesser General Public License Version 2.1          *)
(*         *     (see LICENSE file for the text of the license)         *)
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(* Extraction to Ocaml : special handling of ascii and strings *)

Require Coq.extraction.Extraction.

Require Import Ascii String.

Extract Inductive ascii => char
[
"(* If this appears, you're using Ascii internals. Please don't *)
 (fun (b0,b1,b2,b3,b4,b5,b6,b7) ->
  let f b i = if b then 1 lsl i else 0 in
  Char.chr (f b0 0 + f b1 1 + f b2 2 + f b3 3 + f b4 4 + f b5 5 + f b6 6 + f b7 7))"
]
"(* If this appears, you're using Ascii internals. Please don't *)
 (fun f c ->
  let n = Char.code c in
  let h i = (n land (1 lsl i)) <> 0 in
  f (h 0) (h 1) (h 2) (h 3) (h 4) (h 5) (h 6) (h 7))".

Extract Constant zero => "'\000'".
Extract Constant one => "'\001'".
Extract Constant shift =>
 "fun b c -> Char.chr (((Char.code c) lsl 1) land 255 + if b then 1 else 0)".

Extract Inlined Constant ascii_dec => "(=)".

Extract Inductive string => "char list" [ "[]" "(::)" ].

(*
Definition test := "ceci est un test"%string.
Recursive Extraction test Ascii.zero Ascii.one.
*)