proposition: Lemma strle_to_sumbool (s1 s2 : String) (f : String -> nat) (H' : f s1 < f s2 \/ s1 =s s2) : {f s1 < f s2} + {s1 =s s2}.
proof: Proof. unfold beq in *. case_eq (s1 =s s2). { intro H''; right; reflexivity. } { intro H''; left. destruct H' as [H' | H']; trivial. hnf in *. abstract congruence. } Defined.
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