proposition: Lemma try_add_arc_many_to_many_dec : eq_dec A -> forall l l', incl l' l -> is_restricted R l -> rel_dec R -> rel_dec (try_add_arc_many_to_many l' l).
proof: Proof. induction l'; simpl; intros. hyp. pose (incl_cons_l_incl H). apply try_add_arc_one_to_many_dec with l. hyp. apply H. simpl. tauto. refl. apply restricted_try_add_arc_many_to_many; hyp. tauto. Qed.
imports: Coq(Sumbool Arith) CoLoR(RelDec RelUtil ListUtil RelSub Path LogicUtil)