* @param <V> Value parameter type
 */
@ElementTypesAreNonnullByDefault
final class StandardMutableValueGraph<N, V> extends StandardValueGraph<N, V>
    implements MutableValueGraph<N, V> {

  private final ElementOrder<N> incidentEdgeOrder;

  /** Constructs a mutable graph with the properties specified in {@code builder}. */
  StandardMutableValueGraph(AbstractGraphBuilder<? super N> builder) {
    super(builder);