// string.
func (t Tag) TypeForKey(key string) string {
	if _, start, end, _ := t.findTypeForKey(key); end != start {
		s := t.str[start:end]
		if p := strings.IndexByte(s, '-'); p >= 0 {
			s = s[:p]
		}
		return s
	}
	return ""
}

var (
	errPrivateUse       = errors.New("cannot set a key on a private use tag")

			}
			if onlyChanged && !e.Changed {
				continue
			}
			switch runtime.GOOS {
			default:
				fmt.Fprintf(w, "%s=%s\n", e.Name, shellQuote(e.Value))
			case "plan9":
				if strings.IndexByte(e.Value, '\x00') < 0 {
					fmt.Fprintf(w, "%s='%s'\n", e.Name, strings.ReplaceAll(e.Value, "'", "''"))
				} else {
					v := strings.Split(e.Value, "\x00")
					fmt.Fprintf(w, "%s=(", e.Name)

		}
		shouldBuild = ctxt.eval(x, allTags)

	default:
		shouldBuild = true
		p := content
		for len(p) > 0 {
			line := p
			if i := bytes.IndexByte(line, '\n'); i >= 0 {
				line, p = line[:i], p[i+1:]
			} else {
				p = p[len(p):]
			}
			line = bytes.TrimSpace(line)
			if !bytes.HasPrefix(line, slashSlash) || !bytes.Contains(line, plusBuild) {

					rel.Type = uint8(ri.Symnum & (1<<4 - 1))
				default:
					panic("unreachable")
				}
			}
		}
	}

	return nil
}

func cstring(b []byte) string {
	i := bytes.IndexByte(b, 0)
	if i == -1 {
		i = len(b)
	}
	return string(b[0:i])
}

// Segment returns the first Segment with the given name, or nil if no such segment exists.
func (f *File) Segment(name string) *Segment {

	if l.slice != nil {
		return strings.Join(l.slice, ".")
	}
	return l.orig
}

func (l *labelIter) label() string {
	if l.slice != nil {
		return l.slice[l.i]
	}
	p := strings.IndexByte(l.orig[l.curStart:], '.')
	l.curEnd = l.curStart + p
	if p == -1 {
		l.curEnd = len(l.orig)
	}
	return l.orig[l.curStart:l.curEnd]
}

// mustHaveFieldNameColon ensures that, per RFC 7230, the
// field-name is on a single line, so the first line must
// contain a colon.
func mustHaveFieldNameColon(line []byte) error {
	if bytes.IndexByte(line, ':') < 0 {
		return ProtocolError(fmt.Sprintf("malformed MIME header: missing colon: %q", line))
	}
	return nil
}

var nl = []byte("\n")

	return p.list
}

func (ps *parseState) emph(dst, src []Inline) []Inline {
	const chars = "_*~\"'"
	var stack [len(chars)][]*emphPlain
	stackOf := func(c byte) int {
		return strings.IndexByte(chars, c)
	}

	trimStack := func() {
		for i := range stack {
			stk := &stack[i]
			for len(*stk) > 0 && (*stk)[len(*stk)-1].i >= len(dst) {
				*stk = (*stk)[:len(*stk)-1]
			}
		}
	}

// It is tolerant of unrelated problems in the go.mod file.
func ModulePath(mod []byte) string {
	for len(mod) > 0 {
		line := mod
		mod = nil
		if i := bytes.IndexByte(line, '\n'); i >= 0 {
			line, mod = line[:i], line[i+1:]
		}
		if i := bytes.Index(line, slashSlash); i >= 0 {
			line = line[:i]
		}
		line = bytes.TrimSpace(line)
		if !bytes.HasPrefix(line, moduleStr) {

func Object(pkg *types.Package, p Path) (types.Object, error) {
	pathstr := string(p)
	if pathstr == "" {
		return nil, fmt.Errorf("empty path")
	}

	var pkgobj, suffix string
	if dot := strings.IndexByte(pathstr, opType); dot < 0 {
		pkgobj = pathstr
	} else {
		pkgobj = pathstr[:dot]
		suffix = pathstr[dot:] // suffix starts with "."
	}

	obj := pkg.Scope().Lookup(pkgobj)
	if obj == nil {

		line = line[todo:]
	}
}

// writeWithCRLF writes buf to w but replaces all occurrences of \n with \r\n.
func writeWithCRLF(w io.Writer, buf []byte) (n int, err error) {
	for len(buf) > 0 {
		i := bytes.IndexByte(buf, '\n')
		todo := len(buf)
		if i >= 0 {
			todo = i
		}

		var nn int
		nn, err = w.Write(buf[:todo])
		n += nn
		if err != nil {
			return n, err
		}
		buf = buf[todo:]