case stdFracSecond0:
			// stdFracSecond0 requires the exact number of digits as specified in
			// the layout.
			ndigit := 1 + digitsLen(std)
			if len(value) < ndigit {
				err = errBad
				break
			}
			nsec, rangeErrString, err = parseNanoseconds(value, ndigit)
			value = value[ndigit:]

		case stdFracSecond9:

    return Digit.INSTANCE;
  }

  /**
   * Determines whether a character is a BMP digit according to {@linkplain Character#isDigit(char)
   * Java's definition}. If you only care to match ASCII digits, you can use {@code inRange('0',
   * '9')}.
   *
   * @deprecated Many digits are supplementary characters; see the class documentation.
   * @since 19.0 (since 1.0 as constant {@code JAVA_DIGIT})
   */
  @Deprecated

    return Digit.INSTANCE;
  }

  /**
   * Determines whether a character is a BMP digit according to {@linkplain Character#isDigit(char)
   * Java's definition}. If you only care to match ASCII digits, you can use {@code inRange('0',
   * '9')}.
   *
   * @deprecated Many digits are supplementary characters; see the class documentation.
   * @since 19.0 (since 1.0 as constant {@code JAVA_DIGIT})
   */
  @Deprecated

            """
        ),
    ] = _Unset,
    max_digits: Annotated[
        Union[int, None],
        Doc(
            """
            Maximum number of allow digits for strings.
            """
        ),
    ] = _Unset,
    decimal_places: Annotated[
        Union[int, None],
        Doc(
            """

		if t == "" {
			break
		}
		if c, t, err = nextRune(t); err != nil {
			return 0, "", err
		}
		if c == '{' {
			// Any number of digits in braces.
			// Perl accepts any text at all; it ignores all text
			// after the first non-hex digit. We require only hex digits,
			// and at least one.
			nhex := 0
			r = 0
			for {
				if t == "" {
					break Switch
				}

			name: "chan recv",
			f:    blockChanRecv,
			stk: []string{
				"runtime.chanrecv1",
				"runtime/pprof.blockChanRecv",
				"runtime/pprof.TestBlockProfile",
			},
			re: `
[0-9]+ [0-9]+ @( 0x[[:xdigit:]]+)+
#	0x[0-9a-f]+	runtime\.chanrecv1\+0x[0-9a-f]+	.*runtime/chan.go:[0-9]+
#	0x[0-9a-f]+	runtime/pprof\.blockChanRecv\+0x[0-9a-f]+	.*runtime/pprof/pprof_test.go:[0-9]+

	if hex.DecodedLen(len(val)) > maxLen {
		Exitf("-B option too long (max %d digits): %s", maxLen, ov)
	}

	b, err := hex.DecodeString(val)
	if err != nil {
		if err == hex.ErrLength {
			Exitf("-B argument must have even number of digits: %s", ov)
		}
		if inv, ok := err.(hex.InvalidByteError); ok {
			Exitf("-B argument contains invalid hex digit %c: %s", byte(inv), ov)
		}
		Exitf("-B argument contains invalid hex: %s", ov)

	// Omit trailing zeros up to and including decimal point.
	w := len(buf)
	print := false
	for i := 0; i < prec; i++ {
		digit := v % 10
		print = print || digit != 0
		if print {
			w--
			buf[w] = byte(digit) + '0'
		}
		v /= 10
	}
	if print {
		w--
		buf[w] = '.'
	}
	return w, v
}

// fmtInt formats v into the tail of buf.

		endpointPort,
	)

	// The part of name before the "__" can be up to 205 characters (as with
	// servicePortChainNameBase above). An IPv6 address can be up to 39 characters, and
	// a port can be up to 5 digits, plus 3 punctuation characters gives a max total
	// length of 252, well over chainNameBaseLengthMax (240), so truncation is
	// theoretically possible (though incredibly unlikely).
	return hashAndTruncate(name)
}

	if strings.HasPrefix(name, "_R") {
		return rustToString(name, options)
	}

	// Check for an old-style Rust mangled name.
	// It starts with _ZN and ends with "17h" followed by 16 hex digits
	// followed by "E" followed by an optional suffix starting with "."
	// (which we ignore).
	if strings.HasPrefix(name, "_ZN") {
		rname := name
		if pos := strings.LastIndex(rname, "E."); pos > 0 {