// An IP address can be represented in different formats, to guarantee the uniqueness of the IP,
// the name of the object is the IP address in canonical format, four decimal digits separated
// by dots suppressing leading zeros for IPv4 and the representation defined by RFC 5952 for IPv6.
// Valid: 192.168.1.5 or 2001:db8::1 or 2001:db8:aaaa:bbbb:cccc:dddd:eeee:1

// CastFunc represents CAST sql function
type CastFunc struct {
	Expr     *Expression `parser:" \"CAST\" \"(\" @@ "`
	CastType string      `parser:" \"AS\" @(\"BOOL\" | \"INT\" | \"INTEGER\" | \"STRING\" | \"FLOAT\" | \"DECIMAL\" | \"NUMERIC\" | \"TIMESTAMP\") \")\" "`
}

// SubstringFunc represents SUBSTRING sql function
type SubstringFunc struct {
	Expr *PrimaryTerm `parser:" \"SUBSTRING\" \"(\" @@ "`

   *
   * <p>If the argument is nonnegative, the returned result will be equal to {@code bits},
   * otherwise, the result will be equal to {@code 2^32 + bits}.
   *
   * <p>To represent unsigned decimal constants, consider {@link #valueOf(long)} instead.
   *
   * @since 14.0
   */
  public static UnsignedInteger fromIntBits(int bits) {
    return new UnsignedInteger(bits);
  }

  /**

   *
   * <p>If the argument is nonnegative, the returned result will be equal to {@code bits},
   * otherwise, the result will be equal to {@code 2^64 + bits}.
   *
   * <p>To represent decimal constants less than {@code 2^63}, consider {@link #valueOf(long)}
   * instead.
   *
   * @since 14.0
   */
  public static UnsignedLong fromLongBits(long bits) {

	)

	validCases := []string{
		"count(*)",
		"sum(2 + s.id)",
		"sum(t)",
		"avg(s.id[1])",
		"coalesce(s.id[1], 2, 2 + 3)",

		"cast(s as string)",
		"cast(s AS INT)",
		"cast(s as DECIMAL)",
		"extract(YEAR from '2018-01-09')",
		"extract(month from '2018-01-09')",

		"extract(hour from '2018-01-09')",
		"extract(day from '2018-01-09')",
		"substring('abcd' from 2 for 2)",

     * java.util.regex (where we want them in order to avoid catastrophic backtracking).
     */
    String decimal = "(?:\\d+#(?:\\.\\d*#)?|\\.\\d+#)";
    String completeDec = decimal + "(?:[eE][+-]?\\d+#)?[fFdD]?";
    String hex = "(?:[0-9a-fA-F]+#(?:\\.[0-9a-fA-F]*#)?|\\.[0-9a-fA-F]+#)";
    String completeHex = "0[xX]" + hex + "[pP][+-]?\\d+#[fFdD]?";

	// The size field ends at the first space.
	nStr, rest, ok := strings.Cut(s, " ")
	if !ok {
		return "", "", s, ErrHeader
	}

	// Parse the first token as a decimal integer.
	n, perr := strconv.ParseInt(nStr, 10, 0) // Intentionally parse as native int
	if perr != nil || n < 5 || n > int64(len(s)) {
		return "", "", s, ErrHeader
	}

    // contain non-decimal characters.
    int length = end - start;
    if (length <= 0 || length > 3) {
      throw new NumberFormatException();
    }
    // Disallow leading zeroes, because no clear standard exists on
    // whether these should be interpreted as decimal or octal.
    if (length > 1 && ipString.charAt(start) == '0') {

		return
	}

	switch {
	case majorVersion <= 6:
		res = ESSUnsupported
	default:
		res = ESSSupported
	}
	return
}

// magic HH-256 key as HH-256 hash of the first 100 decimals of π as utf-8 string with a zero key.
var magicHighwayHash256Key = []byte("\x4b\xe7\x34\xfa\x8e\x23\x8a\xcd\x26\x3e\x83\xe6\xbb\x96\x85\x52\x04\x0f\x93\x5d\xa3\x9f\x44\x14\x97\xe0\x9d\x13\x22\xde\x36\xa0")

//
// Note that the GNU manual says that numeric values should be encoded in octal
// format. However, the GNU tar utility itself outputs these values in decimal.
// As such, this library treats values as being encoded in decimal.
func readGNUSparseMap1x0(r io.Reader) (sparseDatas, error) {
	var (
		cntNewline int64
		buf        bytes.Buffer
		blk        block
	)