address[b++] = value.toByte()
  }

  // Check for too few groups. We wanted exactly four.
  return b == addressOffset + 4
}

/** Encodes an IPv6 address in canonical form according to RFC 5952. */
internal fun inet6AddressToAscii(address: ByteArray): String {
  // Go through the address looking for the longest run of 0s. Each group is 2-bytes.
  // A run must be longer than one group (section 4.2.2).

              | (1L << (37 - 2))
              | (1L << (41 - 2))
              | (1L << (43 - 2))
              | (1L << (47 - 2))
              | (1L << (53 - 2))
              | (1L << (59 - 2))
              | (1L << (61 - 2));
      // Look up n within the mask.
      return ((mask >> ((int) n - 2)) & 1) != 0;
    }

    if ((SIEVE_30 & (1 << (n % 30))) != 0) {
      return false;