// WalkOptions provides filtering, marker and other Walk() specific options.
type WalkOptions struct {
	Filter       func(info FileInfo) bool // return WalkFilter returns 'true/false'
	Marker       string                   // set to skip until this object
	LatestOnly   bool                     // returns only latest versions for all matching objects
	AskDisks     string                   // dictates how many disks are being listed

  /**
   * Returns {@code true} if there are no differences between the two maps; that is, if the maps are
   * equal.
   */
  boolean areEqual();

  /**
   * Returns an unmodifiable map containing the entries from the left map whose keys are not present
   * in the right map.
   */
  Map<K, V> entriesOnlyOnLeft();

  /**

  //
  // Graph-level accessors
  //

  /** Returns all nodes in this graph, in the order specified by {@link #nodeOrder()}. */
  @Override
  Set<N> nodes();

  /** Returns all edges in this graph. */
  @Override
  Set<EndpointPair<N>> edges();

  //
  // Graph properties
  //

  /**
   * Returns true if the edges in this graph are directed. Directed edges connect a {@link

  //
  // Graph-level accessors
  //

  /** Returns all nodes in this graph, in the order specified by {@link #nodeOrder()}. */
  @Override
  Set<N> nodes();

  /** Returns all edges in this graph. */
  @Override
  Set<EndpointPair<N>> edges();

  //
  // Graph properties
  //

  /**
   * Returns true if the edges in this graph are directed. Directed edges connect a {@link

     * @return True if there are errors, false otherwise.
     */
    public boolean hasError() {
        return hasError;
    }

    /**
     * Returns the list of errors.
     * @return The list of errors.
     */
    public List<Throwable> getErrors() {
        return errors;
    }

    /**
     * Returns the time taken for the operation.
     * @return The time taken in milliseconds.

   * Returns a view of the supplied {@code iterator} that removes each element from the supplied
   * {@code iterator} as it is returned.
   *
   * <p>The provided iterator must support {@link Iterator#remove()} or else the returned iterator
   * will fail on the first call to {@code next}. The returned {@link Iterator} is also not
   * thread-safe.
   *
   * @param iterator the iterator to remove and return elements from

   * implementing your own stats collector.
   */
  public long requestCount() {
    return saturatedAdd(hitCount, missCount);
  }

  /** Returns the number of times {@link Cache} lookup methods have returned a cached value. */
  public long hitCount() {
    return hitCount;
  }

  /**
   * Returns the ratio of cache requests which were hits. This is defined as {@code hitCount /

   * implementing your own stats collector.
   */
  public long requestCount() {
    return saturatedAdd(hitCount, missCount);
  }

  /** Returns the number of times {@link Cache} lookup methods have returned a cached value. */
  public long hitCount() {
    return hitCount;
  }

  /**
   * Returns the ratio of cache requests which were hits. This is defined as {@code hitCount /

   */
  public static <E> ImmutableList<E> of(E e1) {
    return new SingletonImmutableList<>(e1);
  }

  /**
   * Returns an immutable list containing the given elements, in order.
   *
   * @throws NullPointerException if any element is null
   */
  public static <E> ImmutableList<E> of(E e1, E e2) {
    return construct(e1, e2);
  }

  /**
   * Returns an immutable list containing the given elements, in order.

    val c1 = factory.newConnection(pool, routeA1, 50L)

    // Running at time 50, the pool returns that nothing can be evicted until time 150.
    assertThat(pool.closeConnections(50L)).isEqualTo(100L)
    assertThat(pool.connectionCount()).isEqualTo(1)
    assertThat(c1.socket().isClosed).isFalse()

    // Running at time 60, the pool returns that nothing can be evicted until time 150.
    assertThat(pool.closeConnections(60L)).isEqualTo(90L)