func ExampleErrorf() {
	const name, id = "bueller", 17
	err := fmt.Errorf("user %q (id %d) not found", name, id)
	fmt.Println(err.Error())

	// Output: user "bueller" (id 17) not found
}

func ExampleFscanf() {
	var (
		i int
		b bool
		s string
	)
	r := strings.NewReader("5 true gophers")
	n, err := fmt.Fscanf(r, "%d %t %s", &i, &b, &s)
	if err != nil {
		fmt.Fprintf(os.Stderr, "Fscanf: %v\n", err)
	}