proposition: Lemma beq_to_string {s s'} : to_string s = to_string s' <-> s =s s'.
proof: Proof. split. { intro H; apply bool_eq_from_get; intro n. rewrite <- !nth_to_string, H; reflexivity. } { intro; setoid_subst_rel beq. reflexivity. } Qed.
imports: Fiat.Common.Coq__8_4__8_5__Compat Coq.ZArith.ZArith Fiat.Common Fiat.Common.List.Operations Fiat.Common.List.ListFacts Fiat.Common.Le Fiat.Common.Tactics.SetoidSubst Fiat.Common.Tactics.IsClosed Fiat.Parsers.StringLike.Core Fiat.Common.UIP