return waitFor(asyncClosingCallable, AsyncClosingCallable.class);
    }

    @SuppressWarnings("unchecked") // proxy for a generic class
    <T, U> ClosingFunction<T, U> waitFor(ClosingFunction<T, U> closingFunction) {
      return waitFor(closingFunction, ClosingFunction.class);
    }

    @SuppressWarnings("unchecked") // proxy for a generic class

 * {@link #transform(ClosingFunction, Executor)} or {@link #transformAsync(AsyncClosingFunction,
 * Executor)} on the input step.
 *
 * <h4>Catching</h4>
 *
 * To derive the next step from a failed input step, call {@link #catching(Class, ClosingFunction,
 * Executor)} or {@link #catchingAsync(Class, AsyncClosingFunction, Executor)} on the input step.
 *

 * {@link #transform(ClosingFunction, Executor)} or {@link #transformAsync(AsyncClosingFunction,
 * Executor)} on the input step.
 *
 * <h4>Catching</h4>
 *
 * To derive the next step from a failed input step, call {@link #catching(Class, ClosingFunction,
 * Executor)} or {@link #catchingAsync(Class, AsyncClosingFunction, Executor)} on the input step.
 *