/** Prefer {@link Flux#using(Callable, Function)} over more verbose alternatives. */
static final class FluxUsing<R extends AutoCloseable, T> {
  @BeforeTemplate
  Flux<T> before(
      Callable<? extends R> resourceSupplier,
      Function<? super R, ? extends Publisher<? extends T>> sourceSupplier) {
    return Flux.using(resourceSupplier, sourceSupplier, R::close);
  }

  @AfterTemplate
  Flux<T> after(
      Callable<? extends R> resourceSupplier,
      Function<? super R, ? extends Publisher<? extends T>> sourceSupplier) {
    return Flux.using(resourceSupplier, sourceSupplier);
  }
}