/**
 * Low-level, high-performance utility methods related to the {@linkplain Charsets#UTF_8 UTF-8}
 * character encoding. UTF-8 is defined in section D92 of <a
 * href="http://www.unicode.org/versions/Unicode6.2.0/ch03.pdf">The Unicode Standard Core
 * Specification, Chapter 3</a>.
 *
 * <p>The variant of UTF-8 implemented by this class is the restricted definition of UTF-8
 * introduced in Unicode 3.1. One implication of this is that it rejects <a

  }

  fun writeObjectIdentifier(s: String) {
    val utf8 = Buffer().writeUtf8(s)
    val v1 = utf8.readDecimalLong()
    require(utf8.readByte() == '.'.code.toByte())
    val v2 = utf8.readDecimalLong()
    writeVariableLengthLong(v1 * 40 + v2)

    while (!utf8.exhausted()) {
      require(utf8.readByte() == '.'.code.toByte())
      val vN = utf8.readDecimalLong()
      writeVariableLengthLong(vN)
    }
  }

	case 0 <= r && r < utf8.RuneSelf:
		return IndexByte(s, byte(r))
	case r == utf8.RuneError:
		for i := 0; i < len(s); {
			r1, n := utf8.DecodeRune(s[i:])
			if r1 == utf8.RuneError {
				return i
			}
			i += n
		}
		return -1
	case !utf8.ValidRune(r):
		return -1
	default:
		// Search for rune r using the last byte of its UTF-8 encoded form.

	if s.fill+1 >= cap(s.data) {
		s.grow()
	}

	s.data[s.fill] = c
	s.fill++
}

// append encoded rune to scratch buffer
func (s *scratch) addRune(r rune) int {
	if s.fill+utf8.UTFMax >= cap(s.data) {
		s.grow()
	}

	n := utf8.EncodeRune(s.data[s.fill:], r)
	s.fill += n
	return n

func (tag Tag) IsEmpty() bool {
	return tag.Key == ""
}

// Validate checks this tag.
func (tag Tag) Validate() error {
	if len(tag.Key) == 0 || utf8.RuneCountInString(tag.Key) > 128 {
		return errInvalidTagKey
	}

	if utf8.RuneCountInString(tag.Value) > 256 {
		return errInvalidTagValue
	}

	return nil

func FieldsSeq(s []byte) iter.Seq[[]byte] {
	return func(yield func([]byte) bool) {
		start := -1
		for i := 0; i < len(s); {
			size := 1
			r := rune(s[i])
			isSpace := asciiSpace[s[i]] != 0
			if r >= utf8.RuneSelf {
				r, size = utf8.DecodeRune(s[i:])
				isSpace = unicode.IsSpace(r)
			}
			if isSpace {
				if start >= 0 {
					if !yield(s[start:i:i]) {
						return
					}
					start = -1
				}

    current_username_bytes = credentials.username.encode("utf8")
    correct_username_bytes = b"stanleyjobson"
    is_correct_username = secrets.compare_digest(
        current_username_bytes, correct_username_bytes
    )
    current_password_bytes = credentials.password.encode("utf8")
    correct_password_bytes = b"swordfish"
    is_correct_password = secrets.compare_digest(

				case "FieldDelimiter":
					if len(s) != 0 {
						args.FieldDelimiter = s
					}
				case "QuoteCharacter":
					if utf8.RuneCountInString(s) > 1 {
						return fmt.Errorf("unsupported QuoteCharacter '%v'", s)
					}
					args.QuoteCharacter = s
				case "QuoteEscapeCharacter":
					switch utf8.RuneCountInString(s) {
					case 0:
						args.QuoteEscapeCharacter = defaultQuoteEscapeCharacter
					case 1:

):
    current_username_bytes = credentials.username.encode("utf8")
    correct_username_bytes = b"stanleyjobson"
    is_correct_username = secrets.compare_digest(
        current_username_bytes, correct_username_bytes
    )
    current_password_bytes = credentials.password.encode("utf8")
    correct_password_bytes = b"swordfish"
    is_correct_password = secrets.compare_digest(

  constructor(name: String, value: String) : this(name.encodeUtf8(), value.encodeUtf8())

  constructor(name: ByteString, value: String) : this(name, value.encodeUtf8())

  override fun toString(): String = "${name.utf8()}: ${value.utf8()}"

  companion object {
    // Special header names defined in HTTP/2 spec.
    @JvmField val PSEUDO_PREFIX: ByteString = ":".encodeUtf8()

    const val RESPONSE_STATUS_UTF8 = ":status"