[fix merging of chos 
John Meacham <john@repetae.net>**20080301043531] hunk ./Ho/Collected.hs 47
-        choCombinators = choCombinators a `mappend` choCombinators b,
+        choCombinators = choCombinators a `mergeChoCombinators` choCombinators b,
hunk ./Ho/Collected.hs 57
-    ae = runIdentity . annotate (choVarMap cho) (\_ -> return) (\_ -> return) (\_ -> return)
+ --   ae = runIdentity . annotate (choVarMap cho) (\_ -> return) (\_ -> return) (\_ -> return)
hunk ./Ho/Collected.hs 74
-    f c1 c2 = combHead_s (merge (combHead c1) (combHead c2)) c1 { combRules = combRules c1 `Data.List.union`  combRules c2 }
+    f c1 c2 = combRules_s  (combRules c1 `Data.List.union`  combRules c2) . combHead_s (merge (combHead c1) (combHead c2)) $ c1