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/notation/relations/btpred_6.ma".
16 include "basic_2/relocation/fsup.ma".
17 include "basic_2/reduction/lpr.ma".
18 include "basic_2/dynamic/lsubsv.ma".
20 (* "BIG TREE" PARALLEL REDUCTION FOR CLOSURES *******************************)
22 inductive ypr (h) (g) (L1) (T1): relation2 lenv term ≝
23 | ypr_fsup : ∀L2,T2. ⦃L1, T1⦄ ⊃ ⦃L2, T2⦄ → ypr h g L1 T1 L2 T2
24 | ypr_lpr : ∀L2. L1 ⊢ ➡ L2 → ypr h g L1 T1 L2 T1
25 | ypr_cpr : ∀T2. L1 ⊢ T1 ➡ T2 → ypr h g L1 T1 L1 T2
26 | ypr_ssta : ∀T2,l. ⦃h, L1⦄ ⊢ T1 •[h, g] ⦃l+1, T2⦄ → ypr h g L1 T1 L1 T2
27 | ypr_lsubsv: ∀L2. h ⊢ L2 ¡⊑[h, g] L1 → ypr h g L1 T1 L2 T1
31 "'big tree' parallel reduction (closure)"
32 'BTPRed h g L1 T1 L2 T2 = (ypr h g L1 T1 L2 T2).
34 (* Basic properties *********************************************************)
36 lemma ypr_refl: ∀h,g. bi_reflexive … (ypr h g).