Definition compute_funspecs_norepeat (l : list (ident*funspec)) :=
  compute_list_norepet (fst (split l)).

Lemma not_in_funspecs_by_id_i {A B} i (l : list (A * B)) l0 l1 : split l = (l0,l1) -> ~In i l0 -> ~In i (map fst l).