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/computation/fpbs.ma".
16 include "basic_2/computation/csx_lpx.ma".
18 (* CONTEXT-SENSITIVE EXTENDED STRONGLY NORMALIZING TERMS ********************)
20 (* Advanced properties ******************************************************)
22 lemma csx_fpb_conf: ∀h,g,G1,L1,T1. ⦃G1, L1⦄ ⊢ ⬊*[h, g] T1 →
23 ∀G2,L2,T2. ⦃G1, L1, T1⦄ ≽[h, g] ⦃G2, L2, T2⦄ → ⦃G2, L2⦄ ⊢ ⬊*[h, g] T2.
24 #h #g #G1 #L1 #T1 #HT1 #G2 #L2 #T2 *
25 /2 width=5 by csx_cpx_trans, csx_fquq_conf, csx_lpx_conf/
28 lemma csx_fpbs_conf: ∀h,g,G1,L1,T1. ⦃G1, L1⦄ ⊢ ⬊*[h, g] T1 →
29 ∀G2,L2,T2. ⦃G1, L1, T1⦄ ≥[h, g] ⦃G2, L2, T2⦄ → ⦃G2, L2⦄ ⊢ ⬊*[h, g] T2.
30 #h #g #G1 #L1 #T1 #HT1 #G2 #L2 #T2 #H @(fpbs_ind … H) -G2 -L2 -T2
31 /2 width=5 by csx_fpb_conf/
34 lemma csx_lpxs_conf: ∀h,g,G,L1. ∀T:term. ⦃G, L1⦄ ⊢ ⬊*[h, g] T →
35 ∀L2. ⦃G, L1⦄ ⊢ ➡*[h, g] L2 → ⦃G, L2⦄ ⊢ ⬊*[h, g] T.
36 /3 width=5 by csx_fpbs_conf, lpxs_fpbs/