| `N n -> string_of_int n
| `I _ as t -> "(" ^ string_of_term_no_pars_app l (t :> nf) ^ ")"
| `Lam _ as t -> "(" ^ string_of_term_no_pars_lam l t ^ ")"
| `Match(t,(v,ar),bs_lift,bs,args) ->
| `N n -> string_of_int n
| `I _ as t -> "(" ^ string_of_term_no_pars_app l (t :> nf) ^ ")"
| `Lam _ as t -> "(" ^ string_of_term_no_pars_lam l t ^ ")"
| `Match(t,(v,ar),bs_lift,bs,args) ->