proposition: Lemma exists_nonterminal_iff (P : default_nonterminal_carrierT -> Prop) : (exists k, P k) <-> (exists k, P (positive_to_nonterminal k)).
proof: Proof. nonterminal_iff_t. Qed.
imports: Coq.PArith.BinPos Coq.PArith.Pnat Coq.Arith.Arith Coq.FSets.FMapInterface Coq.FSets.FMapPositive Fiat.Parsers.ContextFreeGrammar.Carriers Fiat.Common.List.ListFacts Fiat.Common.List.ListMorphisms Fiat.Common.Prod