add CCArray.rev

src/core/CCArray.ml

@@ -350,6 +350,21 @@ let reverse_in_place a =
     a = [| 6;5;4;3;2;1 |]
 *)
 
+let rev a =
+  let b = Array.copy a in
+  reverse_in_place b;
+  b
+
+(*$Q
+  Q.(array small_int) (fun a -> rev (rev a) = a)
+*)
+
+(*$T
+  rev [| 1; 2; 3 |] = [| 3; 2; 1 |]
+  rev [| 1; 2; |] = [| 2; 1 |]
+  rev [| |] = [| |]
+  *)
+
 let find f a =
   _find (fun _ -> f ) a 0 (Array.length a)
 

src/core/CCArray.mli

@@ -143,6 +143,10 @@ include S with type 'a t := 'a t
 
 val map : ('a -> 'b) -> 'a t -> 'b t
 
+val rev : 'a t -> 'a t
+(** Copy + reverse in place
+    @since NEXT_RELEASE *)
+
 val filter : ('a -> bool) -> 'a t -> 'a t
 (** Filter elements out of the array. Only the elements satisfying
     the given predicate will be kept. *)