SDDBuilder *builder = [SDDBuilder alloc] initWithLogger:nil epool:[SDDEventsPool sharedPool];

[builder addStateMachineWithContext:nil dsl:SDDOCLanguage(
    // Every statemachine can and must have one topstate
    [TopState
        // Two substates
        [A]
        [B]
    ]

    // Since TopState has two descendants, a $Default transition have to be provided to avoid ambiguity.
    // Another choice is using $Initial transition from outter state [.] such as:
    // [.] -> [A]: $Initial
    [TopState] -> [A]: $Default

    // If [A] is the current state and signal 'E1' occurs, it will transit to state [B]
    [A]->[B]: E1
)];

[[SDDEventsPool sharedPool] scheduleEvent:SDDLiteral(E1)];
// Now we are in state [B]

@interface Charles
@end

@implementation Charles
- (void)wakeup {
    NSLog(@"Good morning.")
}

- (void)sayGoodbye {
    NSLog(@"Bye, see ya.");
}

- (void)goToBed {
    NSLog(@"Good night.")
}

@end

int main() {
    Charles *charles = [[Charles alloc] init];

    SDDBuilder *builder = [SDDBuilder alloc] initWithLogger:nil epool:[SDDEventsPool sharedPool];

    [builder addStateMachineWithContext:charles dsl:SDDOCLanguage(
        [Me
            [Awake  
                e: wakeup     // 'e' is short for entering
                x: sayGoodbye // 'x' is short for exiting
            ]
            [Asleep e: goToBed]
        ]

        [.]      -> [Awake]  : $Initial
        [Awake]  -> [Asleep] : Sunset
        [Asleep] -> [Awake]  : Sunrise
    )];
    // Outputs 'Good morning.' for entering initial state [Awake]

    [[SDDEventsPool sharedPool] scheduleEvent:SDDLiteral(Sunset)];
    // Outputs 'Bye, see ya.' for exiting state [Awake]
    // Outputs 'Good night' for entering state [Asleep]

    [[SDDEventsPool sharedPool] scheduleEvent:SDDLiteral(Sunrise)];
    // Outputs 'Good morning.' for entering state [Awake]

    return 0;
)