// if empty then c.prefixPath is used i.e "/skydns"
func CoreDNSPath(prefix string) EtcdOption {
	return func(args *CoreDNS) {
		args.prefixPath = prefix
	}
}

// NewCoreDNS - initialize a new coreDNS set/unset values.
func NewCoreDNS(cfg clientv3.Config, setters ...EtcdOption) (Store, error) {
	etcdClient, err := clientv3.New(cfg)
	if err != nil {
		return nil, err
	}

	args := &CoreDNS{
		etcdClient: etcdClient,

 * invoke methods, they invoke methods on the {@code ForwardingSortedMap}.
 *
 * <p>Each of the {@code standard} methods, where appropriate, use the comparator of the map to test
 * equality for both keys and values, unlike {@code ForwardingMap}.
 *
 * <p>The {@code standard} methods and the collection views they return are not guaranteed to be
 * thread-safe, even when all of the methods that they depend on are thread-safe.
 *

   */
  public final String to(CaseFormat format, String str) {
    checkNotNull(format);
    checkNotNull(str);
    return (format == this) ? str : convert(format, str);
  }

  /** Enum values can override for performance reasons. */
  String convert(CaseFormat format, String s) {
    // deal with camel conversion
    StringBuilder out = null;
    int i = 0;
    int j = -1;

     * @param value the data to associate with the key, may be {@code null} to remove the mapping
     */
    <T> void set(@Nonnull Key<T> key, @Nullable T value);

    /**
     * Associates the specified session data with the given key if the key is currently mapped to the given value. This
     * method provides an atomic compare-and-update of some key's value.
     *

        String version = metadata.getVersion();
        if (Artifact.LATEST_VERSION.equals(version) || Artifact.RELEASE_VERSION.equals(version)) {
            // meta-versions are not valid <version/> values...don't write them.
            metadata.setVersion(null);
        }

        if (changed || !metadataFile.exists()) {
            metadataFile.getParentFile().mkdirs();

                return lx - rx;
            }
        };

        Map<String, Lifecycle> lifecyclesMap = lookupLifecycles();

        // ensure canonical order of standard lifecycles
        return lifecyclesMap.values().stream()
                .peek(l -> Objects.requireNonNull(l.getId(), "A lifecycle must have an id."))
                .sorted(Comparator.comparing(Lifecycle::getId, comparator))
                .collect(Collectors.toList());

    super(delegate);
  }

  public abstract ImmutableBiMap<V, K> inverse();

  @Override
  public ImmutableSet<V> values() {
    return inverse().keySet();
  }

  @CheckForNull
  public final V forcePut(K key, V value) {
    throw new UnsupportedOperationException();
  }

      }
    }
  }

  /** Read a value as bytes without interpretation of its contents. */
  fun readUnknown(): ByteString {
    return source.readByteString(bytesLeft)
  }

  override fun toString(): String = path.joinToString(separator = " / ")

  companion object {
    /**
     * A synthetic value that indicates there's no more bytes. Values with equivalent data may also

                    value = getPropertyValue(value, tokenizer.nextPropertyName());
                    break;
                default:
                    // could not parse expression
                    return null;
            }
        }

        if (value instanceof Optional) {
            value = ((Optional<?>) value).orElse(null);
        }
        return value;
    }

 *       same function with more clarity.
 * </ul>
 *
 * <h3>Warning about performance</h3>
 *
 * <p>Remember that parameter values for message construction must all be computed eagerly, and
 * autoboxing and varargs array creation may happen as well, even when the verification succeeds and