if !ok {
			break
		}
		s.buf.writeByte(b)
	}
	if len(s.buf) == 0 {
		s.errorString("no hex data for %x string")
		return ""
	}
	return string(s.buf)
}

const (
	floatVerbs = "beEfFgGv"

	hugeWid = 1 << 30

	intBits     = 32 << (^uint(0) >> 63)
	uintptrBits = 32 << (^uintptr(0) >> 63)
)

// scanPercent scans a literal percent character.
func (s *ss) scanPercent() {