update in basic_2

[helm.git] / matita / matita / contribs / lambdadelta / basic_2 / dynamic / nta_ind.ma

diff --git a/matita/matita/contribs/lambdadelta/basic_2/dynamic/nta_ind.ma b/matita/matita/contribs/lambdadelta/basic_2/dynamic/nta_ind.ma
new file mode 100644 (file)
index 0000000..2e65504
--- /dev/null
+++ b/matita/matita/contribs/lambdadelta/basic_2/dynamic/nta_ind.ma
@@ -0,0 +1,79 @@
+(**************************************************************************)
+(*       ___                                                              *)
+(*      ||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/dynamic/nta_drops.ma".
+include "basic_2/dynamic/nta_cpms.ma".
+include "basic_2/dynamic/nta_cpcs.ma".
+include "basic_2/dynamic/nta_preserve.ma".
+
+(* NATIVE TYPE ASSIGNMENT FOR TERMS *****************************************)
+
+(* Advanced eliminators *****************************************************)
+
+lemma nta_ind_rest_cnv (h) (Q:relation4 …):
+      (∀G,L,s. Q G L (⋆s) (⋆(next h s))) →
+      (∀G,K,V,W,U.
+        ⦃G,K⦄ ⊢ V :[h] W → ⬆*[1] W ≘ U →
+        Q G K V W → Q G (K.ⓓV) (#0) U
+      ) →
+      (∀G,K,W,U. ⦃G,K⦄ ⊢ W ![h] → ⬆*[1] W ≘ U → Q G (K.ⓛW) (#0) U) →
+      (∀I,G,K,W,U,i.
+        ⦃G,K⦄ ⊢ #i :[h] W → ⬆*[1] W ≘ U →
+        Q G K (#i) W → Q G (K.ⓘ{I}) (#↑i) U
+      ) →
+      (∀p,I,G,K,V,T,U.
+        ⦃G,K⦄ ⊢ V ![h] → ⦃G,K.ⓑ{I}V⦄ ⊢ T :[h] U →
+        Q G (K.ⓑ{I}V) T U → Q G K (ⓑ{p,I}V.T) (ⓑ{p,I}V.U)
+      ) →
+      (∀p,G,L,V,W,T,U.
+        ⦃G,L⦄ ⊢ V :[h] W → ⦃G,L⦄ ⊢ T :[h] ⓛ{p}W.U →
+        Q G L V W → Q G L T (ⓛ{p}W.U) → Q G L (ⓐV.T) (ⓐV.ⓛ{p}W.U)
+      ) →
+      (∀G,L,T,U. ⦃G,L⦄ ⊢ T :[h] U → Q G L T U → Q G L (ⓝU.T) U
+      ) →
+      (∀G,L,T,U1,U2.
+        ⦃G,L⦄ ⊢ T :[h] U1 → ⦃G,L⦄ ⊢ U1 ⬌*[h] U2 → ⦃G,L⦄ ⊢ U2 ![h] →
+        Q G L T U1 → Q G L T U2
+      ) →
+      ∀G,L,T,U. ⦃G,L⦄ ⊢ T :[h] U → Q G L T U.
+#h #Q #IH1 #IH2 #IH3 #IH4 #IH5 #IH6 #IH7 #IH8 #G #L #T
+@(fqup_wf_ind_eq (Ⓣ) … G L T) -G -L -T #G0 #L0 #T0 #IH #G #L * * [|||| * ]
+[ #s #HG #HL #HT #X #H destruct -IH
+  elim (nta_inv_sort_sn … H) -H #HUX #HX
+  /2 width=4 by/
+| * [| #i ] #HG #HL #HT #X #H destruct
+  [ elim (nta_inv_lref_sn_drops_cnv … H) -H *
+    [ #K #V #W #U #H #HVW #HWU #HUX #HX
+      lapply (drops_fwd_isid … H ?) -H [ // ] #H destruct
+      /5 width=7 by nta_ldef, fqu_fqup, fqu_lref_O/
+    | #K #W #U #H #HW #HWU #HUX #HX
+      lapply (drops_fwd_isid … H ?) -H [ // ] #H destruct
+      /3 width=4 by nta_ldec_cnv/
+    ]
+  | elim (nta_inv_lref_sn … H) -H #I #K #T #U #HT #HTU #HUX #HX #H destruct
+    /5 width=7 by nta_lref, fqu_fqup/
+  ]
+| #l #HG #HL #HT #U #H destruct -IH
+  elim (nta_inv_gref_sn … H)
+| #p #I #V #T #HG #HL #HT #X #H destruct
+  elim (nta_inv_bind_sn_cnv … H) -H #U #HV #HTU #HUX #HX
+  /4 width=5 by nta_bind_cnv/
+| #V #T #HG #HL #HT #X #H destruct
+  elim (nta_inv_appl_sn … H) -H #p #W #U #HVW #HTU #HUX #HX
+  /4 width=9 by nta_appl/
+| #U #T #HG #HL #HT #X #H destruct
+  elim (nta_inv_cast_sn … H) -H #HTU #HUX #HX
+  /4 width=4 by nta_cast/
+]
+qed-.