(* * Copyright (c) 2009 Robert Dockins and Aquinas Hobor. * *)
(* Coq development: using indirection theory to model types in l-calculus *)
(* lam_ref_mach_lemmas.v: various boring lemmas about the machine *)
(* COERCIONS *)
(* DECIDABILTY *)
(* SUBSTITUTION *)

Lemma subst_env_Update: forall rho e1 e2 e3,
subst_env rho (Update e1 e2 e3) =
Update (subst_env rho e1) (subst_env rho e2) (subst_env rho e3).