+import "StandardLibrary"
+
+Foo ?x :-
+ @enforce 1
+ Execute (?x := (1 :: Integer))
+
+Bar ?x :-
+ @enforce 2
+ Execute (if getRef ?x == 1 then () else fail "Test failed.")
+
+rule DoIt where
+ @from
+ ?x = ref (0 :: Integer)
+
+ @to
+ Bar ?x
+ Foo ?x
+
+main :: ()
+main = transformation OneShotForward where
+--
+()