mkock

type speaker interface {
	speak() string
}

type cat struct{}

func (c *cat) speak() string { return "Miau!" }

type dog struct{}

mkock

type myError struct{}

func (m *myError) Error() string {
	return "failure"
}

func doSomething() (string, error) {
	return "", nil
}

mkock

type myError struct{}

func (m *myError) Error() string {
	return "failure"
}

func doSomething() (string, *myError) {
	return "", nil
}

mkock

func doToast(t toaster) {
	t.toast()
}

mkock

type toaster interface {
	toast()
}

type acmeToaster struct {}

func (a *acmeToaster) toast() { fmt.Println("Commencing toasting of bread...") }

mkock

type monster struct {
	damage int
}

func (m *monster) attack() int {
	return m.damage
}

type attacker interface {
	attack() int

mkock

type empty interface {}

mkock

// Verify that acmeToaster satisfies interface toaster.
var _ toaster = &acmeToaster{}

mkock

type toaster interface {
	toast()
}

type acmeToaster struct {}

func (a *acmeToaster) toast() { fmt.Println("Commencing toasting of bread...") }

func doToast(t toaster) {
	t.toast()

mkock

type Vehicle interface {
	Start()
	Stop()
}

type Car struct {}

func (c *Car) Start() {
	fmt.Println("starting engine...")
}