* 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]?";

}

// Allowed cast types
const (
	castBool      = "BOOL"
	castInt       = "INT"
	castInteger   = "INTEGER"
	castString    = "STRING"
	castFloat     = "FLOAT"
	castDecimal   = "DECIMAL"
	castNumeric   = "NUMERIC"
	castTimestamp = "TIMESTAMP"
)

func (e *Expression) castTo(r Record, castType string, tableAlias string) (res *Value, err error) {
	v, err := e.evalNode(r, tableAlias)

	// . followed by 1 or more digits
	if c == '.' {
		isFloat = true
		d.scratch.add(c)

		// first char following must be digit
		if c = d.next(); c < '0' || c > '9' {
			return 0, d.mkError(ErrSyntax, "after decimal point in numeric literal")
		}
		d.scratch.add(c)

		for {
			if d.remaining() == 0 {
				return 0, d.mkError(ErrUnexpectedEOF)
			}
			if c = d.next(); c < '0' || c > '9' {
				break
			}

<p>
A floating-point literal is a decimal or hexadecimal representation of a
<a href="#Constants">floating-point constant</a>.
</p>

<p>
A decimal floating-point literal consists of an integer part (decimal digits),
a decimal point, a fractional part (decimal digits), and an exponent part
(<code>e</code> or <code>E</code> followed by an optional sign and decimal digits).

        fileBuilder.append(".tmp")
        dirtyFiles += directory / fileBuilder.toString()
        fileBuilder.setLength(truncateTo)
      }
    }

    /** Set lengths using decimal numbers like "10123". */
    @Throws(IOException::class)
    internal fun setLengths(strings: List<String>) {
      if (strings.size != valueCount) {
        invalidLengths(strings)
      }

      try {

      return Arrays.copyOfRange(array, start, end);
    }

    @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 0;
  }

  /**
   * Parses the specified string as a signed decimal integer value. The ASCII character {@code '-'}
   * (<code>'&#92;u002D'</code>) is recognized as the minus sign.
   *
   * <p>Unlike {@link Integer#parseInt(String)}, this method returns {@code null} instead of

				if !field.PrimaryKey &&
					(len(matches2) == 1 && matches2[0][1] != fmt.Sprint(length) && ok) {
					alterColumn = true
				}
			}
		}
	}

	// check precision
	if realDataType == "decimal" || realDataType == "numeric" &&
		regexp.MustCompile(realDataType+`\(.*\)`).FindString(fullDataType) != "" { // if realDataType has no precision,ignore
		precision, scale, ok := columnType.DecimalSize()
		if ok {

      }
      asciiDigits = result;
    }

    static int digit(char c) {
      return (c < 128) ? asciiDigits[c] : -1;
    }
  }

  /**
   * Parses the specified string as a signed decimal long value. The ASCII character {@code '-'} (
   * <code>'&#92;u002D'</code>) is recognized as the minus sign.
   *
   * <p>Unlike {@link Long#parseLong(String)}, this method returns {@code null} instead of throwing

func (p *Parser) address(operand []lex.Token) obj.Addr {
	p.start(operand)
	addr := obj.Addr{}
	p.operand(&addr)
	return addr
}

// parseScale converts a decimal string into a valid scale factor.
func (p *Parser) parseScale(s string) int8 {
	switch s {
	case "1", "2", "4", "8":
		return int8(s[0] - '0')
	}
	p.errorf("bad scale: %s", s)
	return 0
}

// Amazon's requirements (i.e. DNS naming conventions). It must be 3-63
// characters long, and it must be a sequence of one or more labels
// separated by periods. Each label can contain lowercase ascii
// letters, decimal digits and hyphens, but must not begin or end with
// a hyphen. See:
// http://docs.aws.amazon.com/AmazonS3/latest/dev/BucketRestrictions.html
func IsValidBucketName(bucket string) bool {