feat: add CCVector.clear_and_reset

src/core/CCVector.ml

@@ -131,6 +131,10 @@ let clear v =
   OUnit.assert_bool "empty_after_clear" (Iter.is_empty (to_seq v));
 *)
 
+let clear_and_reset v =
+  v.size <- 0;
+  v.vec <- [||]
+
 let is_empty v = v.size = 0
 
 let push_unsafe_ v x =

src/core/CCVector.mli

@@ -53,6 +53,11 @@ val init : int -> (int -> 'a) -> ('a, 'mut) t
 val clear : ('a, rw) t -> unit
 (** Clear the content of the vector. *)
 
+val clear_and_reset : ('a, rw) t -> unit
+(** Clear the content of the vector, and deallocate the underlying array,
+    removing references to all the elements.
+    @since NEXT_RELEASE *)
+
 val ensure_with : init:'a -> ('a, rw) t -> int -> unit
 (** Hint to the vector that it should have at least the given capacity.
     @param init if [capacity v = 0], used as a filler