1 (**************************************************************************)
4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
10 (* \ / This file is distributed under the terms of the *)
11 (* v GNU General Public License Version 2 *)
13 (**************************************************************************)
15 include "basic_2/unfold/ltpss_sn_ltpss_sn.ma".
16 include "basic_2/reducibility/cpr.ma".
17 include "basic_2/reducibility/lfpr.ma".
19 (* FOCALIZED PARALLEL REDUCTION FOR LOCAL ENVIRONMENTS **********************)
21 (* Advanced properties ****************************************************)
23 lemma lfpr_pair_cpr: ∀L1,L2. ⦃L1⦄ ➡ ⦃L2⦄ → ∀V1,V2. L2 ⊢ V1 ➡ V2 →
24 ∀I. ⦃L1. ⓑ{I} V1⦄ ➡ ⦃L2. ⓑ{I} V2⦄.
25 #L1 #L2 * #L #HL1 #HL2 #V1 #V2 *
26 <(ltpss_sn_fwd_length … HL2) #V #HV1 #HV2 #I
27 lapply (ltpss_sn_tpss_trans_eq … HV2 … HL2) -HV2 #V2
28 @(ex2_intro … (L.ⓑ{I}V)) /2 width=1/ (**) (* explicit constructor *)