}
	// The open bracket must be preceeded by a link-adjacent rune (or by nothing).
	if t := plainText(i - 1); t != "" {
		r, _ := utf8.DecodeLastRuneInString(t)
		if !isLinkAdjacentRune(r) {
			return ""
		}
	}
	// The element after the next must be a ']'.
	if plainText(i+2) != "]" {
		return ""
	}
	// The ']' must be followed by a link-adjacent rune (or by nothing).
	if t := plainText(i + 3); t != "" {

			t.Errorf("%s(%q) = %q; want %q", funcName, tc.in, actual, tc.out)
		}
	}
}

func tenRunes(r rune) string {
	runes := make([]rune, 10)
	for i := range runes {
		runes[i] = r
	}
	return string(runes)
}

// User-defined self-inverse mapping function
func rot13(r rune) rune {
	const step = 13
	if r >= 'a' && r <= 'z' {
		return ((r - 'a' + step) % 26) + 'a'
	}

			ss = 0
			continue
		}
		info := f.info(src, i)
		if info.size == 0 {
			if atEOF {
				// include incomplete runes
				return n, true
			}
			return lastSegStart, true
		}
		// This block needs to be before the next, because it is possible to
		// have an overflow for runes that are starters (e.g. with U+FF9E).
		switch ss.next(info) {
		case ssStarter:
			lastSegStart = i
		case ssOverflow:

// A mapFunc takes a context set to the current rune and writes the mapped
// version to the same context. It may advance the context to the next rune. It
// returns whether a checkpoint is possible: whether the pDst bytes written to
// dst so far won't need changing as we see more source bytes.
type mapFunc func(*context) bool

// A spanFunc takes a context set to the current rune and returns whether this

// Scanners may do rune-at-a-time scanning or ask the ScanState
// to discover the next space-delimited token.
type ScanState interface {
	// ReadRune reads the next rune (Unicode code point) from the input.
	// If invoked during Scanln, Fscanln, or Sscanln, ReadRune() will
	// return EOF after returning the first '\n' or when reading beyond
	// the specified width.
	ReadRune() (r rune, size int, err error)

that is, runes. (This differs from C's printf where the
units are always measured in bytes.) Either or both of the flags
may be replaced with the character '*', causing their values to be
obtained from the next operand (preceding the one to format),
which must be of type int.

For most values, width is the minimum number of runes to output,
padding the formatted form with spaces if necessary.

Jonh Wendell <******@****.***> 1715709579 -0400

Jonh Wendell <******@****.***> 1715709579 -0400

			}
			continue // All other multibyte runes are correctly encoded and assumed printable.
		}
		if r == utf8.RuneError {
			return false
		}
		if (r < ' ' && r != '\t') || r == '`' || r == '\u007F' {
			return false
		}
	}
	return true
}

func unhex(b byte) (v rune, ok bool) {
	c := rune(b)
	switch {
	case '0' <= c && c <= '9':
		return c - '0', true

Nicole LiHui <******@****.***> 1717379705 +0800