X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Frt_transition%2Fcpr.ma;h=978c42b7cb91d2920a50002bb23b9941f32a75a6;hb=bd53c4e895203eb049e75434f638f26b5a161a2b;hp=d5374513aa6a6d8aff14b368ba9fe7cd1e9c17a2;hpb=e9f96fa56226dfd74de214c89d827de0c5018ac7;p=helm.git

diff --git a/matita/matita/contribs/lambdadelta/basic_2/rt_transition/cpr.ma b/matita/matita/contribs/lambdadelta/basic_2/rt_transition/cpr.ma
index d5374513a..978c42b7c 100644
--- a/matita/matita/contribs/lambdadelta/basic_2/rt_transition/cpr.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/rt_transition/cpr.ma
@@ -12,297 +12,135 @@
 (*                                                                        *)
 (**************************************************************************)
 
-include "basic_2/notation/relations/pred_4.ma".
-include "basic_2/static/lsubr.ma".
-include "basic_2/unfold/lstas.ma".
+include "ground_2/xoa/ex_6_6.ma".
+include "ground_2/xoa/ex_7_7.ma".
+include "ground_2/xoa/or_4.ma".
+include "ground_2/insert_eq/insert_eq_0.ma".
+include "basic_2/rt_transition/cpm.ma".
 
-(* CONTEXT-SENSITIVE PARALLEL REDUCTION FOR TERMS ***************************)
-
-(* activate genv *)
-(* Basic_1: includes: pr0_delta1 pr2_delta1 pr2_thin_dx *)
-(* Note: cpr_flat: does not hold in basic_1 *)
-inductive cpr: relation4 genv lenv term term ≝
-| cpr_atom : ∀I,G,L. cpr G L (⓪{I}) (⓪{I})
-| cpr_delta: ∀G,L,K,V,V2,W2,i.
-             ⬇[i] L ≡ K. ⓓV → cpr G K V V2 →
-             ⬆[0, i + 1] V2 ≡ W2 → cpr G L (#i) W2
-| cpr_bind : ∀a,I,G,L,V1,V2,T1,T2.
-             cpr G L V1 V2 → cpr G (L.ⓑ{I}V1) T1 T2 →
-             cpr G L (ⓑ{a,I}V1.T1) (ⓑ{a,I}V2.T2)
-| cpr_flat : ∀I,G,L,V1,V2,T1,T2.
-             cpr G L V1 V2 → cpr G L T1 T2 →
-             cpr G L (ⓕ{I}V1.T1) (ⓕ{I}V2.T2)
-| cpr_zeta : ∀G,L,V,T1,T,T2. cpr G (L.ⓓV) T1 T →
-             ⬆[0, 1] T2 ≡ T → cpr G L (+ⓓV.T1) T2
-| cpr_eps  : ∀G,L,V,T1,T2. cpr G L T1 T2 → cpr G L (ⓝV.T1) T2
-| cpr_beta : ∀a,G,L,V1,V2,W1,W2,T1,T2.
-             cpr G L V1 V2 → cpr G L W1 W2 → cpr G (L.ⓛW1) T1 T2 →
-             cpr G L (ⓐV1.ⓛ{a}W1.T1) (ⓓ{a}ⓝW2.V2.T2)
-| cpr_theta: ∀a,G,L,V1,V,V2,W1,W2,T1,T2.
-             cpr G L V1 V → ⬆[0, 1] V ≡ V2 → cpr G L W1 W2 → cpr G (L.ⓓW1) T1 T2 →
-             cpr G L (ⓐV1.ⓓ{a}W1.T1) (ⓓ{a}W2.ⓐV2.T2)
-.
-
-interpretation "context-sensitive parallel reduction (term)"
-   'PRed G L T1 T2 = (cpr G L T1 T2).
+(* CONTEXT-SENSITIVE PARALLEL R-TRANSITION FOR TERMS ************************)
 
 (* Basic properties *********************************************************)
 
-lemma lsubr_cpr_trans: ∀G. lsub_trans … (cpr G) lsubr.
-#G #L1 #T1 #T2 #H elim H -G -L1 -T1 -T2
-[ //
-| #G #L1 #K1 #V1 #V2 #W2 #i #HLK1 #_ #HVW2 #IHV12 #L2 #HL12
-  elim (lsubr_fwd_drop2_abbr … HL12 … HLK1) -L1 *
-  /3 width=6 by cpr_delta/
-|3,7: /4 width=1 by lsubr_pair, cpr_bind, cpr_beta/
-|4,6: /3 width=1 by cpr_flat, cpr_eps/
-|5,8: /4 width=3 by lsubr_pair, cpr_zeta, cpr_theta/
-]
-qed-.
-
-(* Basic_1: was by definition: pr2_free *)
-lemma tpr_cpr: ∀G,T1,T2. ⦃G, ⋆⦄ ⊢ T1 ➡ T2 → ∀L. ⦃G, L⦄ ⊢ T1 ➡ T2.
-#G #T1 #T2 #HT12 #L
-lapply (lsubr_cpr_trans … HT12 L ?) //
-qed.
-
-(* Basic_1: includes by definition: pr0_refl *)
-lemma cpr_refl: ∀G,T,L. ⦃G, L⦄ ⊢ T ➡ T.
-#G #T elim T -T // * /2 width=1 by cpr_bind, cpr_flat/
+(* Note: cpr_flat: does not hold in basic_1 *)
+(* Basic_1: includes: pr2_thin_dx *)
+lemma cpr_flat: ∀h,I,G,L,V1,V2,T1,T2.
+                ❪G,L❫ ⊢ V1 ➡[h] V2 → ❪G,L❫ ⊢ T1 ➡[h] T2 →
+                ❪G,L❫ ⊢ ⓕ[I]V1.T1 ➡[h] ⓕ[I]V2.T2.
+#h * /2 width=1 by cpm_cast, cpm_appl/
 qed.
 
 (* Basic_1: was: pr2_head_1 *)
-lemma cpr_pair_sn: ∀I,G,L,V1,V2. ⦃G, L⦄ ⊢ V1 ➡ V2 →
-                   ∀T. ⦃G, L⦄ ⊢ ②{I}V1.T ➡ ②{I}V2.T.
-* /2 width=1 by cpr_bind, cpr_flat/ qed.
-
-lemma cpr_delift: ∀G,K,V,T1,L,l. ⬇[l] L ≡ (K.ⓓV) →
-                  ∃∃T2,T. ⦃G, L⦄ ⊢ T1 ➡ T2 & ⬆[l, 1] T ≡ T2.
-#G #K #V #T1 elim T1 -T1
-[ * /2 width=4 by cpr_atom, lift_sort, lift_gref, ex2_2_intro/
-  #i #L #l #HLK elim (lt_or_eq_or_gt i l)
-  #Hil [1,3: /4 width=4 by lift_lref_ge_minus, lift_lref_lt, ylt_inj, yle_inj, ex2_2_intro/ ]
-  destruct
-  elim (lift_total V 0 (i+1)) #W #HVW
-  elim (lift_split … HVW i i) /3 width=6 by cpr_delta, ex2_2_intro/
-| * [ #a ] #I #W1 #U1 #IHW1 #IHU1 #L #l #HLK
-  elim (IHW1 … HLK) -IHW1 #W2 #W #HW12 #HW2
-  [ elim (IHU1 (L. ⓑ{I}W1) (l+1)) -IHU1 /3 width=9 by drop_drop, cpr_bind, lift_bind, ex2_2_intro/
-  | elim (IHU1 … HLK) -IHU1 -HLK /3 width=8 by cpr_flat, lift_flat, ex2_2_intro/
-  ]
-]
-qed-.
-
-fact lstas_cpr_aux: ∀h,G,L,T1,T2,d. ⦃G, L⦄ ⊢ T1 •*[h, d] T2 →
-                    d = 0 → ⦃G, L⦄ ⊢ T1 ➡ T2.
-#h #G #L #T1 #T2 #d #H elim H -G -L -T1 -T2 -d
-/3 width=1 by cpr_eps, cpr_flat, cpr_bind/
-[ #G #L #K #V1 #V2 #W2 #i #d #HLK #_ #HVW2 #IHV12 #H destruct
-  /3 width=6 by cpr_delta/
-| #G #L #K #V1 #V2 #W2 #i #d #_ #_ #_ #_ <plus_n_Sm #H destruct
-]
-qed-.
-
-lemma lstas_cpr: ∀h,G,L,T1,T2. ⦃G, L⦄ ⊢ T1 •*[h, 0] T2 → ⦃G, L⦄ ⊢ T1 ➡ T2.
-/2 width=4 by lstas_cpr_aux/ qed.
-
-(* Basic inversion lemmas ***************************************************)
+lemma cpr_pair_sn: ∀h,I,G,L,V1,V2. ❪G,L❫ ⊢ V1 ➡[h] V2 →
+                   ∀T. ❪G,L❫ ⊢ ②[I]V1.T ➡[h] ②[I]V2.T.
+#h * /2 width=1 by cpm_bind, cpr_flat/
+qed.
 
-fact cpr_inv_atom1_aux: ∀G,L,T1,T2. ⦃G, L⦄ ⊢ T1 ➡ T2 → ∀I. T1 = ⓪{I} →
-                        T2 = ⓪{I} ∨
-                        ∃∃K,V,V2,i. ⬇[i] L ≡ K. ⓓV & ⦃G, K⦄ ⊢ V ➡ V2 &
-                                    ⬆[O, i + 1] V2 ≡ T2 & I = LRef i.
-#G #L #T1 #T2 * -G -L -T1 -T2
-[ #I #G #L #J #H destruct /2 width=1 by or_introl/
-| #L #G #K #V #V2 #T2 #i #HLK #HV2 #HVT2 #J #H destruct /3 width=8 by ex4_4_intro, or_intror/
-| #a #I #G #L #V1 #V2 #T1 #T2 #_ #_ #J #H destruct
-| #I #G #L #V1 #V2 #T1 #T2 #_ #_ #J #H destruct
-| #G #L #V #T1 #T #T2 #_ #_ #J #H destruct
-| #G #L #V #T1 #T2 #_ #J #H destruct
-| #a #G #L #V1 #V2 #W1 #W2 #T1 #T2 #_ #_ #_ #J #H destruct
-| #a #G #L #V1 #V #V2 #W1 #W2 #T1 #T2 #_ #_ #_ #_ #J #H destruct
+(* Basic inversion properties ***********************************************)
+
+lemma cpr_inv_atom1: ∀h,J,G,L,T2. ❪G,L❫ ⊢ ⓪[J] ➡[h] T2 →
+                     ∨∨ T2 = ⓪[J]
+                      | ∃∃K,V1,V2. ❪G,K❫ ⊢ V1 ➡[h] V2 & ⇧*[1] V2 ≘ T2 &
+                                   L = K.ⓓV1 & J = LRef 0
+                      | ∃∃I,K,T,i. ❪G,K❫ ⊢ #i ➡[h] T & ⇧*[1] T ≘ T2 &
+                                   L = K.ⓘ[I] & J = LRef (↑i).
+#h #J #G #L #T2 #H elim (cpm_inv_atom1 … H) -H *
+[2,4:|*: /3 width=8 by or3_intro0, or3_intro1, or3_intro2, ex4_4_intro, ex4_3_intro/ ]
+[ #n #_ #_ #H destruct
+| #n #K #V1 #V2 #_ #_ #_ #_ #H destruct
 ]
 qed-.
 
-lemma cpr_inv_atom1: ∀I,G,L,T2. ⦃G, L⦄ ⊢ ⓪{I} ➡ T2 →
-                     T2 = ⓪{I} ∨
-                     ∃∃K,V,V2,i. ⬇[i] L ≡ K. ⓓV & ⦃G, K⦄ ⊢ V ➡ V2 &
-                                 ⬆[O, i + 1] V2 ≡ T2 & I = LRef i.
-/2 width=3 by cpr_inv_atom1_aux/ qed-.
-
 (* Basic_1: includes: pr0_gen_sort pr2_gen_sort *)
-lemma cpr_inv_sort1: ∀G,L,T2,s. ⦃G, L⦄ ⊢ ⋆s ➡ T2 → T2 = ⋆s.
-#G #L #T2 #s #H
-elim (cpr_inv_atom1 … H) -H //
-* #K #V #V2 #i #_ #_ #_ #H destruct
+lemma cpr_inv_sort1: ∀h,G,L,T2,s. ❪G,L❫ ⊢ ⋆s ➡[h] T2 → T2 = ⋆s.
+#h #G #L #T2 #s #H elim (cpm_inv_sort1 … H) -H //
 qed-.
 
-(* Basic_1: includes: pr0_gen_lref pr2_gen_lref *)
-lemma cpr_inv_lref1: ∀G,L,T2,i. ⦃G, L⦄ ⊢ #i ➡ T2 →
-                     T2 = #i ∨
-                     ∃∃K,V,V2. ⬇[i] L ≡ K. ⓓV & ⦃G, K⦄ ⊢ V ➡ V2 &
-                               ⬆[O, i + 1] V2 ≡ T2.
-#G #L #T2 #i #H
-elim (cpr_inv_atom1 … H) -H /2 width=1 by or_introl/
-* #K #V #V2 #j #HLK #HV2 #HVT2 #H destruct /3 width=6 by ex3_3_intro, or_intror/
+lemma cpr_inv_zero1: ∀h,G,L,T2. ❪G,L❫ ⊢ #0 ➡[h] T2 →
+                     ∨∨ T2 = #0
+                      | ∃∃K,V1,V2. ❪G,K❫ ⊢ V1 ➡[h] V2 & ⇧*[1] V2 ≘ T2 &
+                                   L = K.ⓓV1.
+#h #G #L #T2 #H elim (cpm_inv_zero1 … H) -H *
+/3 width=6 by ex3_3_intro, or_introl, or_intror/
+#n #K #V1 #V2 #_ #_ #_ #H destruct
 qed-.
 
-lemma cpr_inv_gref1: ∀G,L,T2,p. ⦃G, L⦄ ⊢ §p ➡ T2 → T2 = §p.
-#G #L #T2 #p #H
-elim (cpr_inv_atom1 … H) -H //
-* #K #V #V2 #i #_ #_ #_ #H destruct
+lemma cpr_inv_lref1: ∀h,G,L,T2,i. ❪G,L❫ ⊢ #↑i ➡[h] T2 →
+                     ∨∨ T2 = #(↑i)
+                      | ∃∃I,K,T. ❪G,K❫ ⊢ #i ➡[h] T & ⇧*[1] T ≘ T2 & L = K.ⓘ[I].
+#h #G #L #T2 #i #H elim (cpm_inv_lref1 … H) -H *
+/3 width=6 by ex3_3_intro, or_introl, or_intror/
 qed-.
 
-fact cpr_inv_bind1_aux: ∀G,L,U1,U2. ⦃G, L⦄ ⊢ U1 ➡ U2 →
-                        ∀a,I,V1,T1. U1 = ⓑ{a,I}V1. T1 → (
-                        ∃∃V2,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L.ⓑ{I}V1⦄ ⊢ T1 ➡ T2 &
-                                 U2 = ⓑ{a,I}V2.T2
-                        ) ∨
-                        ∃∃T. ⦃G, L.ⓓV1⦄ ⊢ T1 ➡ T & ⬆[0, 1] U2 ≡ T &
-                             a = true & I = Abbr.
-#G #L #U1 #U2 * -L -U1 -U2
-[ #I #G #L #b #J #W1 #U1 #H destruct
-| #L #G #K #V #V2 #W2 #i #_ #_ #_ #b #J #W #U1 #H destruct
-| #a #I #G #L #V1 #V2 #T1 #T2 #HV12 #HT12 #b #J #W #U1 #H destruct /3 width=5 by ex3_2_intro, or_introl/
-| #I #G #L #V1 #V2 #T1 #T2 #_ #_ #b #J #W #U1 #H destruct
-| #G #L #V #T1 #T #T2 #HT1 #HT2 #b #J #W #U1 #H destruct /3 width=3 by ex4_intro, or_intror/
-| #G #L #V #T1 #T2 #_ #b #J #W #U1 #H destruct
-| #a #G #L #V1 #V2 #W1 #W2 #T1 #T2 #_ #_ #_ #b #J #W #U1 #H destruct
-| #a #G #L #V1 #V #V2 #W1 #W2 #T1 #T2 #_ #_ #_ #_ #b #J #W #U1 #H destruct
-]
-qed-.
-
-lemma cpr_inv_bind1: ∀a,I,G,L,V1,T1,U2. ⦃G, L⦄ ⊢ ⓑ{a,I}V1.T1 ➡ U2 → (
-                     ∃∃V2,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L.ⓑ{I}V1⦄ ⊢ T1 ➡ T2 &
-                              U2 = ⓑ{a,I}V2.T2
-                     ) ∨
-                     ∃∃T. ⦃G, L.ⓓV1⦄ ⊢ T1 ➡ T & ⬆[0, 1] U2 ≡ T &
-                          a = true & I = Abbr.
-/2 width=3 by cpr_inv_bind1_aux/ qed-.
-
-(* Basic_1: includes: pr0_gen_abbr pr2_gen_abbr *)
-lemma cpr_inv_abbr1: ∀a,G,L,V1,T1,U2. ⦃G, L⦄ ⊢ ⓓ{a}V1.T1 ➡ U2 → (
-                     ∃∃V2,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L. ⓓV1⦄ ⊢ T1 ➡ T2 &
-                              U2 = ⓓ{a}V2.T2
-                     ) ∨
-                     ∃∃T. ⦃G, L.ⓓV1⦄ ⊢ T1 ➡ T & ⬆[0, 1] U2 ≡ T & a = true.
-#a #G #L #V1 #T1 #U2 #H
-elim (cpr_inv_bind1 … H) -H *
-/3 width=5 by ex3_2_intro, ex3_intro, or_introl, or_intror/
-qed-.
-
-(* Basic_1: includes: pr0_gen_abst pr2_gen_abst *)
-lemma cpr_inv_abst1: ∀a,G,L,V1,T1,U2. ⦃G, L⦄ ⊢ ⓛ{a}V1.T1 ➡ U2 →
-                     ∃∃V2,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L.ⓛV1⦄ ⊢ T1 ➡ T2 &
-                              U2 = ⓛ{a}V2.T2.
-#a #G #L #V1 #T1 #U2 #H
-elim (cpr_inv_bind1 … H) -H *
-[ /3 width=5 by ex3_2_intro/
-| #T #_ #_ #_ #H destruct
-]
-qed-.
-
-fact cpr_inv_flat1_aux: ∀G,L,U,U2. ⦃G, L⦄ ⊢ U ➡ U2 →
-                        ∀I,V1,U1. U = ⓕ{I}V1.U1 →
-                        ∨∨ ∃∃V2,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L⦄ ⊢ U1 ➡ T2 &
-                                    U2 = ⓕ{I} V2. T2
-                         | (⦃G, L⦄ ⊢ U1 ➡ U2 ∧ I = Cast)
-                         | ∃∃a,V2,W1,W2,T1,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L⦄ ⊢ W1 ➡ W2 &
-                                               ⦃G, L.ⓛW1⦄ ⊢ T1 ➡ T2 & U1 = ⓛ{a}W1.T1 &
-                                               U2 = ⓓ{a}ⓝW2.V2.T2 & I = Appl
-                         | ∃∃a,V,V2,W1,W2,T1,T2. ⦃G, L⦄ ⊢ V1 ➡ V & ⬆[0,1] V ≡ V2 &
-                                                 ⦃G, L⦄ ⊢ W1 ➡ W2 & ⦃G, L.ⓓW1⦄ ⊢ T1 ➡ T2 &
-                                                 U1 = ⓓ{a}W1.T1 &
-                                                 U2 = ⓓ{a}W2.ⓐV2.T2 & I = Appl.
-#G #L #U #U2 * -L -U -U2
-[ #I #G #L #J #W1 #U1 #H destruct
-| #G #L #K #V #V2 #W2 #i #_ #_ #_ #J #W #U1 #H destruct
-| #a #I #G #L #V1 #V2 #T1 #T2 #_ #_ #J #W #U1 #H destruct
-| #I #G #L #V1 #V2 #T1 #T2 #HV12 #HT12 #J #W #U1 #H destruct /3 width=5 by or4_intro0, ex3_2_intro/
-| #G #L #V #T1 #T #T2 #_ #_ #J #W #U1 #H destruct
-| #G #L #V #T1 #T2 #HT12 #J #W #U1 #H destruct /3 width=1 by or4_intro1, conj/
-| #a #G #L #V1 #V2 #W1 #W2 #T1 #T2 #HV12 #HW12 #HT12 #J #W #U1 #H destruct /3 width=11 by or4_intro2, ex6_6_intro/
-| #a #G #L #V1 #V #V2 #W1 #W2 #T1 #T2 #HV1 #HV2 #HW12 #HT12 #J #W #U1 #H destruct /3 width=13 by or4_intro3, ex7_7_intro/
-]
+lemma cpr_inv_gref1: ∀h,G,L,T2,l. ❪G,L❫ ⊢ §l ➡[h] T2 → T2 = §l.
+#h #G #L #T2 #l #H elim (cpm_inv_gref1 … H) -H //
 qed-.
 
-lemma cpr_inv_flat1: ∀I,G,L,V1,U1,U2. ⦃G, L⦄ ⊢ ⓕ{I}V1.U1 ➡ U2 →
-                     ∨∨ ∃∃V2,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L⦄ ⊢ U1 ➡ T2 &
-                                 U2 = ⓕ{I}V2.T2
-                      | (⦃G, L⦄ ⊢ U1 ➡ U2 ∧ I = Cast)
-                      | ∃∃a,V2,W1,W2,T1,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L⦄ ⊢ W1 ➡ W2 &
-                                            ⦃G, L.ⓛW1⦄ ⊢ T1 ➡ T2 & U1 = ⓛ{a}W1.T1 &
-                                            U2 = ⓓ{a}ⓝW2.V2.T2 & I = Appl
-                      | ∃∃a,V,V2,W1,W2,T1,T2. ⦃G, L⦄ ⊢ V1 ➡ V & ⬆[0,1] V ≡ V2 &
-                                              ⦃G, L⦄ ⊢ W1 ➡ W2 & ⦃G, L.ⓓW1⦄ ⊢ T1 ➡ T2 &
-                                              U1 = ⓓ{a}W1.T1 &
-                                              U2 = ⓓ{a}W2.ⓐV2.T2 & I = Appl.
-/2 width=3 by cpr_inv_flat1_aux/ qed-.
-
-(* Basic_1: includes: pr0_gen_appl pr2_gen_appl *)
-lemma cpr_inv_appl1: ∀G,L,V1,U1,U2. ⦃G, L⦄ ⊢ ⓐV1.U1 ➡ U2 →
-                     ∨∨ ∃∃V2,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L⦄ ⊢ U1 ➡ T2 &
-                                 U2 = ⓐV2.T2
-                      | ∃∃a,V2,W1,W2,T1,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L⦄ ⊢ W1 ➡ W2 &
-                                            ⦃G, L.ⓛW1⦄ ⊢ T1 ➡ T2 &
-                                            U1 = ⓛ{a}W1.T1 & U2 = ⓓ{a}ⓝW2.V2.T2
-                      | ∃∃a,V,V2,W1,W2,T1,T2. ⦃G, L⦄ ⊢ V1 ➡ V & ⬆[0,1] V ≡ V2 &
-                                              ⦃G, L⦄ ⊢ W1 ➡ W2 & ⦃G, L.ⓓW1⦄ ⊢ T1 ➡ T2 &
-                                              U1 = ⓓ{a}W1.T1 & U2 = ⓓ{a}W2.ⓐV2.T2.
-#G #L #V1 #U1 #U2 #H elim (cpr_inv_flat1 … H) -H *
-[ /3 width=5 by or3_intro0, ex3_2_intro/
-| #_ #H destruct
-| /3 width=11 by or3_intro1, ex5_6_intro/
-| /3 width=13 by or3_intro2, ex6_7_intro/
-]
-qed-.
-
-(* Note: the main property of simple terms *)
-lemma cpr_inv_appl1_simple: ∀G,L,V1,T1,U. ⦃G, L⦄ ⊢ ⓐV1. T1 ➡ U → 𝐒⦃T1⦄ →
-                            ∃∃V2,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L⦄ ⊢ T1 ➡ T2 &
-                                     U = ⓐV2. T2.
-#G #L #V1 #T1 #U #H #HT1
-elim (cpr_inv_appl1 … H) -H *
-[ /2 width=5 by ex3_2_intro/
-| #a #V2 #W1 #W2 #U1 #U2 #_ #_ #_ #H #_ destruct
-  elim (simple_inv_bind … HT1)
-| #a #V #V2 #W1 #W2 #U1 #U2 #_ #_ #_ #_ #H #_ destruct
-  elim (simple_inv_bind … HT1)
-]
+(* Basic_1: includes: pr0_gen_cast pr2_gen_cast *)
+lemma cpr_inv_cast1: ∀h,G,L,V1,U1,U2. ❪G,L❫ ⊢ ⓝ V1.U1 ➡[h] U2 →
+                     ∨∨ ∃∃V2,T2. ❪G,L❫ ⊢ V1 ➡[h] V2 & ❪G,L❫ ⊢ U1 ➡[h] T2 &
+                                 U2 = ⓝV2.T2
+                      | ❪G,L❫ ⊢ U1 ➡[h] U2.
+#h #G #L #V1 #U1 #U2 #H elim (cpm_inv_cast1 … H) -H
+/2 width=1 by or_introl, or_intror/ * #n #_ #H destruct
 qed-.
 
-(* Basic_1: includes: pr0_gen_cast pr2_gen_cast *)
-lemma cpr_inv_cast1: ∀G,L,V1,U1,U2. ⦃G, L⦄ ⊢ ⓝ V1. U1 ➡ U2 → (
-                     ∃∃V2,T2. ⦃G, L⦄ ⊢ V1 ➡ V2 & ⦃G, L⦄ ⊢ U1 ➡ T2 &
-                              U2 = ⓝ V2. T2
-                     ) ∨ ⦃G, L⦄ ⊢ U1 ➡ U2.
-#G #L #V1 #U1 #U2 #H elim (cpr_inv_flat1 … H) -H *
-[ /3 width=5 by ex3_2_intro, or_introl/
-| /2 width=1 by or_intror/
-| #a #V2 #W1 #W2 #T1 #T2 #_ #_ #_ #_ #_ #H destruct
-| #a #V #V2 #W1 #W2 #T1 #T2 #_ #_ #_ #_ #_ #_ #H destruct
+lemma cpr_inv_flat1: ∀h,I,G,L,V1,U1,U2. ❪G,L❫ ⊢ ⓕ[I]V1.U1 ➡[h] U2 →
+                     ∨∨ ∃∃V2,T2. ❪G,L❫ ⊢ V1 ➡[h] V2 & ❪G,L❫ ⊢ U1 ➡[h] T2 &
+                                 U2 = ⓕ[I]V2.T2
+                      | (❪G,L❫ ⊢ U1 ➡[h] U2 ∧ I = Cast)
+                      | ∃∃p,V2,W1,W2,T1,T2. ❪G,L❫ ⊢ V1 ➡[h] V2 & ❪G,L❫ ⊢ W1 ➡[h] W2 &
+                                            ❪G,L.ⓛW1❫ ⊢ T1 ➡[h] T2 & U1 = ⓛ[p]W1.T1 &
+                                            U2 = ⓓ[p]ⓝW2.V2.T2 & I = Appl
+                      | ∃∃p,V,V2,W1,W2,T1,T2. ❪G,L❫ ⊢ V1 ➡[h] V & ⇧*[1] V ≘ V2 &
+                                              ❪G,L❫ ⊢ W1 ➡[h] W2 & ❪G,L.ⓓW1❫ ⊢ T1 ➡[h] T2 &
+                                              U1 = ⓓ[p]W1.T1 &
+                                              U2 = ⓓ[p]W2.ⓐV2.T2 & I = Appl.
+#h * #G #L #V1 #U1 #U2 #H
+[ elim (cpm_inv_appl1 … H) -H *
+  /3 width=13 by or4_intro0, or4_intro2, or4_intro3, ex7_7_intro, ex6_6_intro, ex3_2_intro/
+| elim (cpr_inv_cast1 … H) -H [ * ]
+  /3 width=5 by or4_intro0, or4_intro1, ex3_2_intro, conj/
 ]
 qed-.
 
-(* Basic forward lemmas *****************************************************)
-
-lemma cpr_fwd_bind1_minus: ∀I,G,L,V1,T1,T. ⦃G, L⦄ ⊢ -ⓑ{I}V1.T1 ➡ T → ∀b.
-                           ∃∃V2,T2. ⦃G, L⦄ ⊢ ⓑ{b,I}V1.T1 ➡ ⓑ{b,I}V2.T2 &
-                                    T = -ⓑ{I}V2.T2.
-#I #G #L #V1 #T1 #T #H #b
-elim (cpr_inv_bind1 … H) -H *
-[ #V2 #T2 #HV12 #HT12 #H destruct /3 width=4 by cpr_bind, ex2_2_intro/
-| #T2 #_ #_ #H destruct
+(* Basic eliminators ********************************************************)
+
+lemma cpr_ind (h): ∀Q:relation4 genv lenv term term.
+                   (∀I,G,L. Q G L (⓪[I]) (⓪[I])) →
+                   (∀G,K,V1,V2,W2. ❪G,K❫ ⊢ V1 ➡[h] V2 → Q G K V1 V2 →
+                     ⇧*[1] V2 ≘ W2 → Q G (K.ⓓV1) (#0) W2
+                   ) → (∀I,G,K,T,U,i. ❪G,K❫ ⊢ #i ➡[h] T → Q G K (#i) T →
+                     ⇧*[1] T ≘ U → Q G (K.ⓘ[I]) (#↑i) (U)
+                   ) → (∀p,I,G,L,V1,V2,T1,T2. ❪G,L❫ ⊢ V1 ➡[h] V2 → ❪G,L.ⓑ[I]V1❫ ⊢ T1 ➡[h] T2 →
+                     Q G L V1 V2 → Q G (L.ⓑ[I]V1) T1 T2 → Q G L (ⓑ[p,I]V1.T1) (ⓑ[p,I]V2.T2)
+                   ) → (∀I,G,L,V1,V2,T1,T2. ❪G,L❫ ⊢ V1 ➡[h] V2 → ❪G,L❫ ⊢ T1 ➡[h] T2 →
+                     Q G L V1 V2 → Q G L T1 T2 → Q G L (ⓕ[I]V1.T1) (ⓕ[I]V2.T2)
+                   ) → (∀G,L,V,T1,T,T2. ⇧*[1] T ≘ T1 → ❪G,L❫ ⊢ T ➡[h] T2 →
+                     Q G L T T2 → Q G L (+ⓓV.T1) T2
+                   ) → (∀G,L,V,T1,T2. ❪G,L❫ ⊢ T1 ➡[h] T2 → Q G L T1 T2 →
+                     Q G L (ⓝV.T1) T2
+                   ) → (∀p,G,L,V1,V2,W1,W2,T1,T2. ❪G,L❫ ⊢ V1 ➡[h] V2 → ❪G,L❫ ⊢ W1 ➡[h] W2 → ❪G,L.ⓛW1❫ ⊢ T1 ➡[h] T2 →
+                     Q G L V1 V2 → Q G L W1 W2 → Q G (L.ⓛW1) T1 T2 →
+                     Q G L (ⓐV1.ⓛ[p]W1.T1) (ⓓ[p]ⓝW2.V2.T2)
+                   ) → (∀p,G,L,V1,V,V2,W1,W2,T1,T2. ❪G,L❫ ⊢ V1 ➡[h] V → ❪G,L❫ ⊢ W1 ➡[h] W2 → ❪G,L.ⓓW1❫ ⊢ T1 ➡[h] T2 →
+                     Q G L V1 V → Q G L W1 W2 → Q G (L.ⓓW1) T1 T2 →
+                     ⇧*[1] V ≘ V2 → Q G L (ⓐV1.ⓓ[p]W1.T1) (ⓓ[p]W2.ⓐV2.T2)
+                   ) →
+                   ∀G,L,T1,T2. ❪G,L❫ ⊢ T1 ➡[h] T2 → Q G L T1 T2.
+#h #Q #IH1 #IH2 #IH3 #IH4 #IH5 #IH6 #IH7 #IH8 #IH9 #G #L #T1 #T2
+@(insert_eq_0 … 0) #n #H
+@(cpm_ind … H) -G -L -T1 -T2 -n [2,4,11:|*: /3 width=4 by/ ]
+[ #G #L #s #H destruct
+| #n #G #K #V1 #V2 #W2 #_ #_ #_ #H destruct
+| #n #G #L #U1 #U2 #T #_ #_ #H destruct
 ]
 qed-.
 
-(* Basic_1: removed theorems 11:
+(* Basic_1: removed theorems 12:
             pr0_subst0_back pr0_subst0_fwd pr0_subst0
+            pr0_delta1
             pr2_head_2 pr2_cflat clear_pr2_trans
             pr2_gen_csort pr2_gen_cflat pr2_gen_cbind
             pr2_gen_ctail pr2_ctail
 *)
-(* Basic_1: removed local theorems 4:
-            pr0_delta_eps pr0_cong_delta
-            pr2_free_free pr2_free_delta
-*)