public static void Main(string[] args)
{
var consoleOutput = new ConsoleOutput();
var light = new DiningRoomLight();
var powerUpLight = new Func <object>(() => PowerUpLight(light));
var powerDownLight = new Func <object>(() => PowerDownLight(light));
var machine = new LightSwitchStateMachine(LightSwitchState.SwitchedOff, 0, powerUpLight, powerDownLight);
machine = DispatchSignalTo(machine,
whenSwitchedOn: SwitchedOnSignal.DoesNothing,
whenSwitchedOff: SwitchedOnSignal.PowersDownTheLight
);
machine = DispatchSignalTo(machine,
SwitchedOffSignal.PowersDownTheLight,
SwitchedOffSignal.DoesNothing
);
machine = DispatchSignalTo(machine,
whenSwitchedOn: SwitchedOffSignal.PowersDownTheLight,
whenSwitchedOff: SwitchedOffSignal.DoesNothing
);
var whatever = ShowOutput(consoleOutput, machine.NumSwitches);
}
public static LightSwitchStateMachine PowersDownTheLight(LightSwitchStateMachine arg)
{
var result = arg.PowerUpLight(); //impure
return(new LightSwitchStateMachine(LightSwitchState.SwitchedOn,
arg.NumSwitches + 1,
arg.PowerUpLight,
arg.PowerDownLight));
}
public static LightSwitchStateMachine DispatchSignalTo(
LightSwitchStateMachine machine,
Func <LightSwitchStateMachine, LightSwitchStateMachine> whenSwitchedOn,
Func <LightSwitchStateMachine, LightSwitchStateMachine> whenSwitchedOff)
{
switch (machine.CurrentState)
{
case LightSwitchState.SwitchedOn:
return(whenSwitchedOn(machine));
case LightSwitchState.SwitchedOff:
return(whenSwitchedOff(machine));
default:
throw new ArgumentOutOfRangeException();
}
}
public static LightSwitchStateMachine DoesNothing(LightSwitchStateMachine arg)
{
return(arg);
}
