test(ocaml): add test.ml

test/test.ml

@@ -0,0 +1,183 @@
+
+
+let foo_let = function
+  | A -> "a"
+
+
+
+  | B -> "b"
+
+
+
+  | C -> "c"
+
+
+
+  | D -> "d"
+
+
+
+let bar_let c =
+  match c with
+  | '0' -> Stdlib.int_of_char c
+
+
+
+  | 'a' -> Stdlib.int_of_char c
+
+
+
+  | 'A' -> Stdlib.int_of_char c
+
+
+
+  | _ -> -1
+
+
+let parse_int base s i =
+  let len = String.length s in
+  let rec next prev =
+    let j = !i in
+    if j >= len then prev
+    else
+      let c = s.[j] in
+      let k = int_of_char c in
+      if is_number base k then (
+        incr i;
+        next ((prev * base) + k))
+      else prev
+  in
+  let i = !i in
+  if i < len then
+    if is_number base (int_of_char s.[i]) then next 0 else raise (bad_char i s)
+  else raise (need_more s)
+
+module S128 : sig
+  exception Overflow
+
+  type t
+
+  val shift_right : t -> int -> t
+  val shift_left : t -> int -> t
+  val write_octets_exn : ?off:int -> t -> bytes -> unit
+  val succ_exn : t -> t
+  val succ : t -> (t, [> `Msg of string ]) result
+  val pred : t -> (t, [> `Msg of string ]) result
+end = struct
+  exception Overflow
+
+  type t = string
+
+  let mk_zero () = Bytes.make 16 '\x00'
+  let zero = Bytes.unsafe_to_string (mk_zero ())
+  let max_int = String.make 16 '\xff'
+  let compare = String.compare
+  let equal = String.equal
+
+  let iteri_right2 f x y =
+    for i = 15 downto 0 do
+      let y' = Char.code (String.get y i) in
+      f i x' y'
+    done
+
+
+
+
+
+
+
+
+  let add_exn x y =
+    let b = mk_zero () in
+    let carry = ref 0 in
+    iteri_right2
+      (fun i x' y' ->
+        let sum = x' + y' + !carry in
+        if sum >= 256 then (
+          carry := 1;
+          Bytes.set_uint8 b i (sum - 256))
+        else (
+          carry := 0;
+          Bytes.set_uint8 b i sum))
+      x y;
+    if !carry <> 0 then raise Overflow else Bytes.unsafe_to_string b
+
+  let add x y = try Some (add_exn x y) with Overflow -> None
+
+  let pred_exn x =
+    if equal x zero then raise Overflow;
+    let b = Bytes.of_string x in
+    let rec go i =
+      Bytes.set_uint8 b i (Char.code (String.get x i) - 1);
+      if Char.code (String.get x i) = 0 then go (Stdlib.pred i)
+    in
+    go 15;
+    Bytes.unsafe_to_string b
+
+
+
+
+
+  module Byte = struct
+    (* Extract the [n] least significant bits from [i] *)
+    let get_lsbits n i =
+      if n <= 0 || n > 8 then invalid_arg "out of bounds";
+      i land ((1 lsl n) - 1)
+
+    (* Extract the [n] most significant bits from [i] *)
+    let get_msbits n i =
+      if n <= 0 || n > 8 then invalid_arg "out of bounds";
+      (i land (255 lsl (8 - n))) lsr (8 - n)
+
+    (* Set value [x] in [i]'s [n] most significant bits *)
+    let set_msbits n x i =
+      if n < 0 || n > 8 then raise (Invalid_argument "n must be >= 0 && <= 8")
+      else if n = 0 then i
+      else if n = 8 then x
+      else (x lsl (8 - n)) lor i
+
+    (* set bits are represented as true *)
+    let fold_left f a i =
+      let bitmask = ref 0b1000_0000 in
+      let a' = ref a in
+      for _ = 0 to 7 do
+        a' := f !a' (i land !bitmask > 0);
+        bitmask := !bitmask lsr 1
+      done;
+      !a'
+  end
+
+end
+
+let bar n =
+  match Domain_name.count_labels n with
+  | 6 -> (
+      match V4.of_domain_name n with None -> None | Some x -> Some (V4 x))
+  | 34 -> (
+      match V6.of_domain_name n with None -> None | Some x -> Some (V6 x))
+  | _ -> None
+
+let succ = function
+  | V4 addr -> Result.map (fun v -> V4 v) (V4.succ addr)
+  | V6 addr -> Result.map (fun v -> V6 v) (V6.succ addr)
+
+
+module Prefix = struct
+  module Addr = struct
+    let to_v6 = to_v6
+  end
+
+    | None -> None
+
+
+  let foo = function
+    | V1 p -> V1 (V1.foo.of_addr p)
+
+
+
+
+
+    | V6 p -> V6 (V6.foo.of_addr p)
+
+
+end