- "big tree" theorem is now proved up to some conjectures involving

[helm.git] / matita / matita / contribs / lambdadelta / basic_2 / etc / fpbg / fpbg.etc

diff --git a/matita/matita/contribs/lambdadelta/basic_2/etc/fpbg/fpbg.etc b/matita/matita/contribs/lambdadelta/basic_2/etc/fpbg/fpbg.etc
new file mode 100644 (file)
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+++ b/matita/matita/contribs/lambdadelta/basic_2/etc/fpbg/fpbg.etc
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+(**************************************************************************)
+(*       ___                                                              *)
+(*      ||M||                                                             *)
+(*      ||A||       A project by Andrea Asperti                           *)
+(*      ||T||                                                             *)
+(*      ||I||       Developers:                                           *)
+(*      ||T||         The HELM team.                                      *)
+(*      ||A||         http://helm.cs.unibo.it                             *)
+(*      \   /                                                             *)
+(*       \ /        This file is distributed under the terms of the       *)
+(*        v         GNU General Public License Version 2                  *)
+(*                                                                        *)
+(**************************************************************************)
+
+include "basic_2/notation/relations/btpredstarproper_8.ma".
+include "basic_2/computation/fpbc.ma".
+
+(* GENEARAL "BIG TREE" PROPER PARALLEL COMPUTATION FOR CLOSURES *************)
+
+(* Note: this is not transitive *)
+inductive fpbg (h) (g) (G1) (L1) (T1): relation3 genv lenv term ≝
+| fpbg_cpxs: ∀L2,T2. ⦃G1, L1⦄ ⊢ T1 ➡*[h, g] T2 → (T1 = T2 → ⊥) → ⦃G1, L1⦄ ⊢ ➡*[h, g] L2 →
+             fpbg h g G1 L1 T1 G1 L2 T2
+| fpbg_fqup: ∀G2,L,L2,T,T2. ⦃G1, L1⦄ ⊢ T1 ➡*[h, g] T → ⦃G1, L1, T⦄ ⊃+ ⦃G2, L, T2⦄ → ⦃G2, L⦄ ⊢ ➡*[h, g] L2 →
+             fpbg h g G1 L1 T1 G2 L2 T2
+| fpbg_lpxs: ∀G2,L,L0,L2,T,T2. ⦃G1, L1⦄ ⊢ T1 ➡*[h, g] T → ⦃G1, L1, T⦄ ⊃* ⦃G2, L, T2⦄ → ⦃G2, L⦄ ⊢ ➡*[h, g] L0 →
+             (L ⋕[0, T2] L0 → ⊥) → ⦃G2, L0⦄ ⊢ ➡*[h, g] L2 → L0 ⋕[0, T2] L2 →
+             fpbg h g G1 L1 T1 G2 L2 T2
+.
+
+interpretation "'big tree' proper parallel computation (closure)"
+   'BTPRedStarProper h g G1 L1 T1 G2 L2 T2 = (fpbg h g G1 L1 T1 G2 L2 T2).
+
+(* Basic properties *********************************************************)
+
+lemma fpbc_fpbg: ∀h,g,G1,G2,L1,L2,T1,T2. ⦃G1, L1, T1⦄ ≻[h, g] ⦃G2, L2, T2⦄ →
+                 ⦃G1, L1, T1⦄ >[h, g] ⦃G2, L2, T2⦄.
+#h #g #G1 #G2 #L1 #L2 #T1 #T2 * -G2 -L2 -T2
+/3 width=9 by fpbg_fqup, fpbg_cpxs, fpbg_lpxs/
+qed.