proposition: Lemma open_exp_wrt_exp_lc_exp : forall e2 e1, lc_exp e2 -> open_exp_wrt_exp e2 e1 = e2.
proof: Proof. unfold open_exp_wrt_exp; default_simp. Qed.
imports: Coq.Logic.FunctionalExtensionality Coq.Program.Equality Metalib.Metatheory Metalib.LibLNgen Stlc