Trait aper::StateProgram[−][src]

pub trait StateProgram: StateMachine<Transition = TransitionEvent<Self::T>> {
    type T: Transition;
    fn new(init_value: &str) -> Self;

    fn suspended_event(&self) -> Option<TransitionEvent<Self::T>> { ... }
}
Expand description

This trait can be added to a StateMachine which takes a TransitionEvent as its transition. Only state machines with this trait can be used directly with the aper client/server infrastructure.

Associated Types

Required methods

Provided methods

A state machine may “suspend” an event which occurs at a specific time in the future. This is useful for ensuring that the state is updated at a future time regardless of a user-initiated state change before then. State machines that only change state as a result of user-initiated events can ignore this method, as the default implementation is to never suspend an event.

This method is called by the server once after every call to process_event. If it returns None, no event is suspended, and any previously suspended event is canceled. If it returns Some, the provided event becomes the “suspended” event, replacing the prior suspended event if there was one.

Only one event can be suspended at a time. If a state machine wants to be triggered for multiple events in the future, it is up to that state machine to return the (chronologically) next event each time this method is called.

Currently, only the state machine running on the server ever has this method called.

Since they are not associated with a particular player, suspended events trigger process_event with a None as the player in the TransitionEvent.

Implementors