import java.util.concurrent.ConcurrentSkipListMap;
import org.jspecify.annotations.NullUnmarked;

/**
 * Helper classes for various benchmarks.
 *
 * @author Christopher Swenson
 */
@NullUnmarked
final class BenchmarkHelpers {
  /** So far, this is the best way to test various implementations of {@link Set} subclasses. */
  public interface CollectionsImplEnum {
    <E extends Comparable<E>> Collection<E> create(Collection<E> contents);