[sledge] Add Vector.unzip

Reviewed By: jvillard

Differential Revision: D16905895

fbshipit-source-id: 98891d4b0

sledge/src/import/vector.ml

@@ -81,5 +81,10 @@ let of_list x = v (Array.of_list x)
 let of_list_rev x = v (Array.of_list_rev x)
 let of_option x = v (Option.to_array x)
 let reduce_exn x ~f = Array.reduce_exn (a x) ~f
+
+let unzip x =
+  let y, z = Array.unzip (a x) in
+  (v y, v z)
+
 let to_list x = Array.to_list (a x)
 let to_array = a

sledge/src/import/vector.mli

@@ -175,7 +175,9 @@ val reduce_exn : 'a t -> f:('a -> 'a -> 'a) -> 'a
 (* val random_element_exn : ?random_state:Base.Random.State.t -> 'a t -> 'a *)
 (* val zip : 'a t -> 'b t -> ('a * 'b) t option *)
 (* val zip_exn : 'a t -> 'b t -> ('a * 'b) t *)
-(* val unzip : ('a * 'b) t -> 'a t * 'b t *)
+
+val unzip : ('a * 'b) t -> 'a t * 'b t
+
 (* val sorted_copy : 'a t -> compare:('a -> 'a -> int) -> 'a t *)
 (* val last : 'a t -> 'a *)