re-frame-fsm.md

You create a fsm via an effect:

(reg-event-fx
  :id
  (fn [_ _])
    {:fsm  {:create {:id   123
                     :initial-state {}
                     :log-fn  (fn [fsm-db db trigger new-state] ...)
                     :start  (fn [XXX]  )
                     :on-complete  (fn [XXX]  )
                     :machine {
                            [:state1  :trigger  :new-state  :action :guard]
                            [:state1  :trigger  :new-state  :action :guard]
                            [:state2  :trigger  :new-state  :action 
                    }
                    :terminal-states  [:state2]
                    :actions {
                        :action (fn [fsm-db trigger]  {:fsm-db)
                    }
                    :guards {
                        :guard-id  (fn [fsm-db])
                    }
                    }
  )

You trigger the FSM in one of two ways:

1. Via an effect
2. or via a dispatch to s special event handler

(dispatch [:fsm  :id  :trigger  :other-args}])

I have to work out how actions can act like event handlers, but be syncronous.

Subscriptions:

(subscribe [:fsm :id :path-within-state])

fsm-db:

{:id   XXX
 :state XXX
 :spec  {}     ;; read-only description of the machine
 :data  {}}    ;; additional state matained by the machine 

Notes:

• Where is fsm state stored? Has to be app-db
• XXX is there a need for on-start. That should be
• XXX how to know when complete
• XXX means installing an effect handler and special event handler so triggers can be
• XXX Will we need the ability to order effects?
• XXX