//! Looping state machine //! //! An example of a state machine which will loop between State 2 and State 3. //! A picture depicting the state machine can be found in the README. #![deny(missing_docs)] use smlang::statemachine; statemachine! { transitions: { *State1 + Event1 = State2, State2 + Event2 = State3, State3 + Event3 = State2, } } /// Context pub struct Context; impl StateMachineContext for Context {} fn main() { let mut sm = StateMachine::new(Context); assert!(matches!(sm.state(), &States::State1)); let r = sm.process_event(Events::Event1); assert!(matches!(r, Ok(&States::State2))); let r = sm.process_event(Events::Event2); assert!(matches!(r, Ok(&States::State3))); // Go back in the loop a few time let r = sm.process_event(Events::Event3); assert!(matches!(r, Ok(&States::State2))); let r = sm.process_event(Events::Event2); assert!(matches!(r, Ok(&States::State3))); let r = sm.process_event(Events::Event3); assert!(matches!(r, Ok(&States::State2))); // Now we cannot use Event1 again, as it is outside the state machine loop let r = sm.process_event(Events::Event1); assert!(matches!(r, Err(Error::InvalidEvent))); assert!(matches!(sm.state(), &States::State2)); }