Add FLS.remove

lib/picos/bootstrap/picos_bootstrap.ml

@@ -499,6 +499,10 @@ module Fiber = struct
         r.fls <- fls;
         Array.unsafe_set fls key
           (Sys.opaque_identity (Obj.magic value : non_float))
+
+    let remove (type a) (Fiber r : fiber) (key : a t) =
+      let fls = r.fls in
+      if key < Array.length fls then Array.unsafe_set fls key unique
   end
 end
 

lib/picos/picos.mli

@@ -994,6 +994,13 @@ module Fiber : sig
 
         ⚠️ It is only safe to call [set] from the fiber itself or when the fiber
         is known not to be running. *)
+
+    val remove : fiber -> 'a t -> unit
+    (** [remove fiber key] removes the value, if any, associated with the [key]
+        from the storage associated with the [fiber].
+
+        ⚠️ It is only safe to call [remove] from the fiber itself or when the
+        fiber is known not to be running. *)
   end
 
   (** {2 Interface for spawning} *)

test/test_picos.ml

@@ -29,6 +29,8 @@ let test_fls_basics =
       Fiber.FLS.set fiber float_key 4.2;
       Fiber.FLS.set fiber counter_key (Atomic.fetch_and_add counter 1);
       assert (Fiber.FLS.get_exn fiber float_key = 4.2);
+      Fiber.FLS.remove fiber float_key;
+      assert (Fiber.FLS.get fiber float_key ~default:1.01 = 1.01);
       assert (Fiber.FLS.get_exn fiber counter_key = 0)
     end;
     begin