+
+-- In which phase should the specialise-constructor rules be active?
+-- Originally I made them always-active, but Manuel found that
+-- this defeated some clever user-written rules. So Plan B
+-- is to make them active only in Phase 0; after all, currently,
+-- the specConstr transformation is only run after the simplifier
+-- has reached Phase 0. In general one would want it to be
+-- flag-controllable, but for now I'm leaving it baked in
+-- [SLPJ Oct 01]
+specConstrActivation :: Activation
+specConstrActivation = ActiveAfter 0 -- Baked in; see comments above