If you are satisfied with a dummy method on an interface, you can continue by adding more types to that interface. Color is not a great example, so: type V

If you are satisfied with a dummy method on an interface, you can continue by adding more types to that interface. Color is not a great example, so: type Vehicle interface { isVehicle() } type Car struct {} func (c Car) isVehicle() {} type Van struct {} func (v Van) isVehicle() {} func VehicleType(vehicle Vehicle) { switch v := vehicle.(type) { case Car: fmt.Println("car") case Van: fmt.Println("van") default: fmt.Println("unknown vehicle") } This covers most, but not all, of the bases, in that you don't get exhaustiveness checking at compile time, unless you adjoin a linter to your compile process: https://github.com/BurntSushi/go-sumtype https://github.com/BurntSushi/go-sumtype