}
	for _, r := range v {
		if !httpguts.IsTokenRune(r) {
			return false
		}
		if 'A' <= r && r <= 'Z' {
			return false
		}
	}
	return true
}

func http2httpCodeString(code int) string {
	switch code {
	case 200:
		return "200"
	case 404:
		return "404"
	}
	return strconv.Itoa(code)
}

// from pkg io
type http2stringWriter interface {