proposition: Lemma sub_nonterminals_listT_remove_2 {ls ls' ps} (H : sub_nonterminals_listT ls ls') : sub_nonterminals_listT (remove_nonterminal ls ps) ls'.
proof: Proof. etransitivity; eauto using sub_nonterminals_listT_remove. Qed.
imports: Fiat.Common.Coq__8_4__8_5__Compat Coq.Classes.RelationClasses Coq.Setoids.Setoid Coq.ZArith.ZArith Fiat.Parsers.ContextFreeGrammar.Core Fiat.Parsers.BaseTypes