From ba7e0d9e1e305ca93cd783d942baccaa859eaa64 Mon Sep 17 00:00:00 2001
From: Dirk Ziegelmeier <dirk@ziegelmeier.net>
Date: Fri, 23 Aug 2024 06:59:51 +0200
Subject: [PATCH] Eliminate "unhandled" special state

---
 include/cpp_event_framework/Statemachine.hxx | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/include/cpp_event_framework/Statemachine.hxx b/include/cpp_event_framework/Statemachine.hxx
index 2dbbce6..810261d 100644
--- a/include/cpp_event_framework/Statemachine.hxx
+++ b/include/cpp_event_framework/Statemachine.hxx
@@ -191,6 +191,12 @@ public:
             }
         }
 
+        /**
+         * @brief Construct a new Statemachine Transition object
+         * Use Statemachine::UnhandledEvent() instead
+         *
+         */
+        constexpr Transition() noexcept = default;
         /**
          * @brief Construct a new Statemachine Transition object
          * Use Statemachine::TransitionTo() instead
@@ -508,9 +514,9 @@ public:
             }
 
             s = s->parent_;
-        } while ((transition.target_ == &kUnhandled) && (s != nullptr));
+        } while ((transition.target_ == nullptr) && (s != nullptr));
 
-        if ((transition.target_ != &kUnhandled))
+        if ((transition.target_ != nullptr))
         {
             if (transition.target_ != &kNone)
             {
@@ -592,7 +598,7 @@ public:
      */
     static inline Transition UnhandledEvent()
     {
-        return Transition(kUnhandled);
+        return Transition();
     }
 
     /**
@@ -674,10 +680,6 @@ public:
      * @brief No transition
      */
     static const State kNone;
-    /**
-     * @brief Unhandled transition
-     */
-    static const State kUnhandled;
     /**
      * @brief Event deferral request
      */
@@ -832,9 +834,6 @@ template <typename Impl, typename Event, PolymorphicAllocatorProvider Allocator>
 const typename Statemachine<Impl, Event, Allocator>::State Statemachine<Impl, Event, Allocator>::kNone =
     typename Statemachine<Impl, Event, Allocator>::State("None", nullptr);
 template <typename Impl, typename Event, PolymorphicAllocatorProvider Allocator>
-const typename Statemachine<Impl, Event, Allocator>::State Statemachine<Impl, Event, Allocator>::kUnhandled =
-    typename Statemachine<Impl, Event, Allocator>::State("Unhandled", nullptr);
-template <typename Impl, typename Event, PolymorphicAllocatorProvider Allocator>
 const typename Statemachine<Impl, Event, Allocator>::State Statemachine<Impl, Event, Allocator>::kInTransition =
     typename Statemachine<Impl, Event, Allocator>::State("InTransition", nullptr);
 template <typename Impl, typename Event, PolymorphicAllocatorProvider Allocator>