*/
    public <V extends @Nullable Object> ClosingFuture<V> callAsync(
        AsyncCombiningCallable<V> combiningCallable, Executor executor) {
      AsyncCallable<V> asyncCallable =
          new AsyncCallable<V>() {
            @Override
            public ListenableFuture<V> call() throws Exception {
              return new Peeker(inputs).callAsync(combiningCallable, closeables);
            }

     * handleAllCompleted(), they will already have been nulled out. But in the case of
     * whenAll*().call*(), this future may be pending until the callback runs -- or even longer in
     * the case of callAsync(), which waits for the callback's returned future to complete.
     */
    releaseResources(ALL_INPUT_FUTURES_PROCESSED);
  }

  /**

     *     href="https://errorprone.info/bugpattern/FutureReturnValueIgnored">https://errorprone.info/bugpattern/FutureReturnValueIgnored</a>.
     */
    public <C extends @Nullable Object> ListenableFuture<C> callAsync(
        AsyncCallable<C> combiner, Executor executor) {
      return new CombinedFuture<>(futures, allMustSucceed, executor, combiner);
    }

    /**