* href="http://en.wikipedia.org/wiki/Memoization">memoization</a>
   *
   * <p>The returned supplier is thread-safe. The supplier's serialized form does not contain the
   * cached value, which will be recalculated when {@code get()} is called on the reserialized
   * instance. The actual memoization does not happen when the underlying delegate throws an
   * exception.
   *

   * network that does not allow them will throw an {@link IllegalArgumentException}.
   */
  boolean allowsParallelEdges();

  /**
   * Returns true if this network allows self-loops (edges that connect a node to itself).
   * Attempting to add a self-loop to a network that does not allow them will throw an {@link
   * IllegalArgumentException}.
   */

    @Override
    public boolean add(@ParametricNullness V element) {
      throw new IllegalArgumentException("Key does not satisfy predicate: " + key);
    }

    @Override
    public boolean addAll(Collection<? extends V> collection) {
      checkNotNull(collection);
      throw new IllegalArgumentException("Key does not satisfy predicate: " + key);
    }

    @Override
    protected Set<V> delegate() {

    @Override
    public boolean add(@ParametricNullness V element) {
      throw new IllegalArgumentException("Key does not satisfy predicate: " + key);
    }

    @Override
    public boolean addAll(Collection<? extends V> collection) {
      checkNotNull(collection);
      throw new IllegalArgumentException("Key does not satisfy predicate: " + key);
    }

    @Override
    protected Set<V> delegate() {

   * href="http://en.wikipedia.org/wiki/Memoization">memoization</a>
   *
   * <p>The returned supplier is thread-safe. The supplier's serialized form does not contain the
   * cached value, which will be recalculated when {@code get()} is called on the reserialized
   * instance. The actual memoization does not happen when the underlying delegate throws an
   * exception.
   *

  /**
   * Returns a view of {@code unfiltered} containing all elements that are of the type {@code
   * desiredType}. The returned iterable's iterator does not support {@code remove()}.
   *
   * <p><b>{@code Stream} equivalent:</b> {@code stream.filter(type::isInstance).map(type::cast)}.
   * This does perform a little more work than necessary, so another option is to insert an
   * unchecked cast at some later point:
   *
   * {@snippet :

  }

  /**
   * Returns an {@code UnsignedInteger} holding the value of the specified {@code String}, parsed as
   * an unsigned {@code int} value.
   *
   * @throws NumberFormatException if the string does not contain a parsable unsigned {@code int}
   *     value
   */
  public static UnsignedInteger valueOf(String string) {
    return valueOf(string, 10);
  }

  /**

 *       contains all the right method <i>signatures</i> to implement {@link Iterable}, it does not
 *       actually do so, to avoid implying repeat-iterability.) {@code FluentIterable}, on the other
 *       hand, is multiple-use, and does implement {@link Iterable}.
 *   <li>Streams offer many features not found here, including {@code min/max}, {@code distinct},

 *       contains all the right method <i>signatures</i> to implement {@link Iterable}, it does not
 *       actually do so, to avoid implying repeat-iterability.) {@code FluentIterable}, on the other
 *       hand, is multiple-use, and does implement {@link Iterable}.
 *   <li>Streams offer many features not found here, including {@code min/max}, {@code distinct},

  /**
   * Returns a view of {@code unfiltered} containing all elements that are of the type {@code
   * desiredType}. The returned iterable's iterator does not support {@code remove()}.
   *
   * <p><b>{@code Stream} equivalent:</b> {@code stream.filter(type::isInstance).map(type::cast)}.
   * This does perform a little more work than necessary, so another option is to insert an
   * unchecked cast at some later point:
   *
   * {@snippet :