Fix exit function for transient states.

Author: Nathan-Michaels-Bose

Semantics/Operation.hs

@@ -75,7 +75,8 @@ allHandlers g = fromList $
 finalStates :: Gr EnterExitState Happening -> [Node]
 finalStates g = nodes g \\
     do  (n, EnterExitState {st=st@(State _)}) <- states
-        (Event _, Just (st', ev')) <- toList $ Map.map (! st) ahs
+        (e, Just (st', ev')) <- toList $ Map.map (! st) ahs
+        guard $ canTransition e
         (m, EnterExitState {st=st''}) <- states
         guard $ st' == st''
         (_, _, Happening {flags}) <- out g m
@@ -84,3 +85,6 @@ finalStates g = nodes g \\
     where
         ahs = allHandlers g
         states = labNodes g
+        canTransition EventEnter = True
+        canTransition (Event _) = True
+        canTransition _ = False

examples/showoff.smudge

@@ -8,6 +8,7 @@
     [
         _ -(SM3."External")-> B
     ],
+    D --> A,
     B (@enterB)
     [
         "Whee" --> C,
@@ -17,7 +18,8 @@
   * C
     [
         Beedoo --> A,
-        GoB -(@gob)-> B
+        GoB -(@gob)-> B,
+        something --> D
     ]
 }