-manifestlyWHNF (Var _) = True
-manifestlyWHNF (Lit _) = True
-manifestlyWHNF (Con _ _ _) = True -- ToDo: anything for Prim?
-manifestlyWHNF (Lam _ _) = True
-manifestlyWHNF (CoTyLam _ e) = manifestlyWHNF e
-manifestlyWHNF (SCC _ e) = manifestlyWHNF e
-manifestlyWHNF (Let _ e) = False
-manifestlyWHNF (Case _ _) = False