...

mcc/mcc_finite_state_machine.h

@@ -317,6 +317,7 @@ protected:
     std::vector<std::function<void(const MccFiniteStateMachine*)>> _destroyFunc{};
 
     std::string_view _currentStateID;
+    std::string_view _previousStateID;
     std::vector<std::string_view> _stateID{};
     std::vector<std::string_view> _eventID{};
 
@@ -367,7 +368,7 @@ protected:
 
 public:
     template <traits::fsm_state_c InitStateT>
-    constexpr MccFiniteStateMachine(InitStateT) : _currentStateID(InitStateT::ID)
+    constexpr MccFiniteStateMachine(InitStateT) : _currentStateID(InitStateT::ID), _previousStateID(InitStateT::ID)
     {
         using states_t = deduce_states_t<InitStateT>;
         auto states = std::make_shared<states_t>();
@@ -417,6 +418,7 @@ public:
                                       p_event->onTransit();
                                   }
 
+                                  _previousStateID = curr_state_t::ID;
                                   *currentState = &std::get<to_state_t>(*states);
                                   _currentStateID = to_state_t::ID;
 
@@ -525,6 +527,11 @@ public:
         return _currentStateID;
     }
 
+    std::string_view previousStateID() const
+    {
+        return _previousStateID;
+    }
+
 
     // returns IDs of all deduced unique states