Proof beta_delta_whnf srt_ecc.

(* Specifications: *)
Lemma bd_conv_hnf :
forall (e : env_ecc) (x y : trm_ecc),
ecc_sn e x ->
ecc_sn e y -> decide (conv_hn_inv _ (beta_delta_rule _) e x y).
Lemma bd_conv_hnf :
forall (e : env) (x y : term),
sn e x ->
sn e y -> decide (conv_hn_inv _ (beta_delta_rule _) e x y).