substUnfolding _ NoUnfolding = NoUnfolding
substUnfolding _ (OtherCon cons) = OtherCon cons
substUnfolding env (CompulsoryUnfolding rhs) = CompulsoryUnfolding (substExpr env rhs)
substUnfolding _ NoUnfolding = NoUnfolding
substUnfolding _ (OtherCon cons) = OtherCon cons
substUnfolding env (CompulsoryUnfolding rhs) = CompulsoryUnfolding (substExpr env rhs)