/** Creates a new, empty {@link ExecutionList}. */
  public ExecutionList() {}

  /**
   * Adds the {@code Runnable} and accompanying {@code Executor} to the list of listeners to
   * execute. If execution has already begun, the listener is executed immediately.
   *
   * <p>When selecting an executor, note that {@code directExecutor} is dangerous in some cases. See

   *
   * <p>If a task is {@linkplain Thread#interrupt interrupted} while a task is running:
   *
   * <ol>
   *   <li>execution will not stop until the task queue is empty.
   *   <li>tasks will begin execution with the thread marked as not interrupted - any interruption
   *       applies only to the task that was running at the point of interruption.