func (x *RWS) Seek(offset int64, whence int) (n int64, err error) { return }
func (x *RWS) String() string                                     { return "rws" }

func makeRWS() io.ReadWriteSeeker { return &RWS{} }
func makeStringer() fmt.Stringer  { return &RWS{} }

// Test correct construction of static empty interface values
var efaces = [...]struct {
	x interface{}
	s string
}{
	{nil, "<nil> <nil>"},
	{1, "int 1"},