X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Freduction%2Fcnx.ma;h=2402ccf0bd5f0740bbf5aebeca1922d610559daa;hb=52e675f555f559c047d5449db7fc89a51b977d35;hp=d423f119ea1c07d887bb6e69bd8f8e2f91bfade5;hpb=0733a61e7b3a0f6173b403e3bfc2257b725b44f2;p=helm.git

diff --git a/matita/matita/contribs/lambdadelta/basic_2/reduction/cnx.ma b/matita/matita/contribs/lambdadelta/basic_2/reduction/cnx.ma
index d423f119e..2402ccf0b 100644
--- a/matita/matita/contribs/lambdadelta/basic_2/reduction/cnx.ma
+++ b/matita/matita/contribs/lambdadelta/basic_2/reduction/cnx.ma
@@ -12,52 +12,52 @@
 (*                                                                        *)
 (**************************************************************************)
 
-include "basic_2/notation/relations/normal_5.ma".
+include "basic_2/notation/relations/prednormal_5.ma".
 include "basic_2/reduction/cnr.ma".
 include "basic_2/reduction/cpx.ma".
 
-(* CONTEXT-SENSITIVE EXTENDED NORMAL TERMS **********************************)
+(* NORMAL TERMS FOR CONTEXT-SENSITIVE EXTENDED REDUCTION ********************)
 
 definition cnx: ∀h. sd h → relation3 genv lenv term ≝
                 λh,g,G,L. NF … (cpx h g G L) (eq …).
 
 interpretation
-   "context-sensitive extended normality (term)"
-   'Normal h g L T = (cnx h g L T).
+   "normality for context-sensitive extended reduction (term)"
+   'PRedNormal h g L T = (cnx h g L T).
 
 (* Basic inversion lemmas ***************************************************)
 
-lemma cnx_inv_sort: ∀h,g,G,L,k. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃⋆k⦄ → deg h g k 0.
+lemma cnx_inv_sort: ∀h,g,G,L,k. ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃⋆k⦄ → deg h g k 0.
 #h #g #G #L #k #H elim (deg_total h g k)
 #l @(nat_ind_plus … l) -l // #l #_ #Hkl
-lapply (H (⋆(next h k)) ?) -H /2 width=2 by cpx_sort/ -L -l #H destruct -H -e0 (**) (* destruct does not remove some premises *)
+lapply (H (⋆(next h k)) ?) -H /2 width=2 by cpx_st/ -L -l #H destruct -H -e0 (**) (* destruct does not remove some premises *)
 lapply (next_lt h k) >e1 -e1 #H elim (lt_refl_false … H)
 qed-.
 
-lemma cnx_inv_delta: ∀h,g,I,G,L,K,V,i. ⇩[i] L ≡ K.ⓑ{I}V → ⦃G, L⦄ ⊢ 𝐍[h, g]⦃#i⦄ → ⊥.
+lemma cnx_inv_delta: ∀h,g,I,G,L,K,V,i. ⇩[i] L ≡ K.ⓑ{I}V → ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃#i⦄ → ⊥.
 #h #g #I #G #L #K #V #i #HLK #H
 elim (lift_total V 0 (i+1)) #W #HVW
 lapply (H W ?) -H [ /3 width=7 by cpx_delta/ ] -HLK #H destruct
 elim (lift_inv_lref2_be … HVW) -HVW //
 qed-.
 
-lemma cnx_inv_abst: ∀h,g,a,G,L,V,T. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃ⓛ{a}V.T⦄ →
-                    ⦃G, L⦄ ⊢ 𝐍[h, g]⦃V⦄ ∧ ⦃G, L.ⓛV⦄ ⊢ 𝐍[h, g]⦃T⦄.
+lemma cnx_inv_abst: ∀h,g,a,G,L,V,T. ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃ⓛ{a}V.T⦄ →
+                    ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃V⦄ ∧ ⦃G, L.ⓛV⦄ ⊢ ➡[h, g] 𝐍⦃T⦄.
 #h #g #a #G #L #V1 #T1 #HVT1 @conj
 [ #V2 #HV2 lapply (HVT1 (ⓛ{a}V2.T1) ?) -HVT1 /2 width=2 by cpx_pair_sn/ -HV2 #H destruct //
 | #T2 #HT2 lapply (HVT1 (ⓛ{a}V1.T2) ?) -HVT1 /2 width=2 by cpx_bind/ -HT2 #H destruct //
 ]
 qed-.
 
-lemma cnx_inv_abbr: ∀h,g,G,L,V,T. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃-ⓓV.T⦄ →
-                    ⦃G, L⦄ ⊢ 𝐍[h, g]⦃V⦄ ∧ ⦃G, L.ⓓV⦄ ⊢ 𝐍[h, g]⦃T⦄.
+lemma cnx_inv_abbr: ∀h,g,G,L,V,T. ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃-ⓓV.T⦄ →
+                    ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃V⦄ ∧ ⦃G, L.ⓓV⦄ ⊢ ➡[h, g] 𝐍⦃T⦄.
 #h #g #G #L #V1 #T1 #HVT1 @conj
 [ #V2 #HV2 lapply (HVT1 (-ⓓV2.T1) ?) -HVT1 /2 width=2 by cpx_pair_sn/ -HV2 #H destruct //
 | #T2 #HT2 lapply (HVT1 (-ⓓV1.T2) ?) -HVT1 /2 width=2 by cpx_bind/ -HT2 #H destruct //
 ]
 qed-.
 
-lemma cnx_inv_zeta: ∀h,g,G,L,V,T. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃+ⓓV.T⦄ → ⊥.
+lemma cnx_inv_zeta: ∀h,g,G,L,V,T. ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃+ⓓV.T⦄ → ⊥.
 #h #g #G #L #V #T #H elim (is_lift_dec T 0 1)
 [ * #U #HTU
   lapply (H U ?) -H /2 width=3 by cpx_zeta/ #H destruct
@@ -69,56 +69,66 @@ lemma cnx_inv_zeta: ∀h,g,G,L,V,T. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃+ⓓV.T⦄ → 
 ]
 qed-.
 
-lemma cnx_inv_appl: ∀h,g,G,L,V,T. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃ⓐV.T⦄ →
-                    ∧∧ ⦃G, L⦄ ⊢ 𝐍[h, g]⦃V⦄ & ⦃G, L⦄ ⊢ 𝐍[h, g]⦃T⦄ & 𝐒⦃T⦄.
+lemma cnx_inv_appl: ∀h,g,G,L,V,T. ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃ⓐV.T⦄ →
+                    ∧∧ ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃V⦄ & ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃T⦄ & 𝐒⦃T⦄.
 #h #g #G #L #V1 #T1 #HVT1 @and3_intro
-[ #V2 #HV2 lapply (HVT1 (ⓐV2.T1) ?) -HVT1 /2 width=1/ -HV2 #H destruct //
-| #T2 #HT2 lapply (HVT1 (ⓐV1.T2) ?) -HVT1 /2 width=1/ -HT2 #H destruct //
+[ #V2 #HV2 lapply (HVT1 (ⓐV2.T1) ?) -HVT1 /2 width=1 by cpx_pair_sn/ -HV2 #H destruct //
+| #T2 #HT2 lapply (HVT1 (ⓐV1.T2) ?) -HVT1 /2 width=1 by cpx_flat/ -HT2 #H destruct //
 | generalize in match HVT1; -HVT1 elim T1 -T1 * // #a * #W1 #U1 #_ #_ #H
   [ elim (lift_total V1 0 1) #V2 #HV12
-    lapply (H (ⓓ{a}W1.ⓐV2.U1) ?) -H /3 width=3/ -HV12 #H destruct
-  | lapply (H (ⓓ{a}ⓝW1.V1.U1) ?) -H /3 width=1/ #H destruct
+    lapply (H (ⓓ{a}W1.ⓐV2.U1) ?) -H /3 width=3 by cpr_cpx, cpr_theta/ -HV12 #H destruct
+  | lapply (H (ⓓ{a}ⓝW1.V1.U1) ?) -H /3 width=1 by cpr_cpx, cpr_beta/ #H destruct
   ]
 ]
 qed-.
 
-lemma cnx_inv_tau: ∀h,g,G,L,V,T. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃ⓝV.T⦄ → ⊥.
+lemma cnx_inv_eps: ∀h,g,G,L,V,T. ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃ⓝV.T⦄ → ⊥.
 #h #g #G #L #V #T #H lapply (H T ?) -H
-/2 width=4 by cpx_tau, discr_tpair_xy_y/
+/2 width=4 by cpx_eps, discr_tpair_xy_y/
 qed-.
 
 (* Basic forward lemmas *****************************************************)
 
-lemma cnx_fwd_cnr: ∀h,g,G,L,T. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃T⦄ → ⦃G, L⦄ ⊢ 𝐍⦃T⦄.
+lemma cnx_fwd_cnr: ∀h,g,G,L,T. ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃T⦄ → ⦃G, L⦄ ⊢ ➡ 𝐍⦃T⦄.
 #h #g #G #L #T #H #U #HTU
 @H /2 width=1 by cpr_cpx/ (**) (* auto fails because a δ-expansion gets in the way *)
 qed-.
 
 (* Basic properties *********************************************************)
 
-lemma cnx_sort: ∀h,g,G,L,k. deg h g k 0 → ⦃G, L⦄ ⊢ 𝐍[h, g]⦃⋆k⦄.
+lemma cnx_sort: ∀h,g,G,L,k. deg h g k 0 → ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃⋆k⦄.
 #h #g #G #L #k #Hk #X #H elim (cpx_inv_sort1 … H) -H // * #l #Hkl #_
 lapply (deg_mono … Hkl Hk) -h -L <plus_n_Sm #H destruct
 qed.
 
-lemma cnx_sort_iter: ∀h,g,G,L,k,l. deg h g k l → ⦃G, L⦄ ⊢ 𝐍[h, g]⦃⋆((next h)^l k)⦄.
+lemma cnx_sort_iter: ∀h,g,G,L,k,l. deg h g k l → ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃⋆((next h)^l k)⦄.
 #h #g #G #L #k #l #Hkl
 lapply (deg_iter … l Hkl) -Hkl <minus_n_n /2 width=6 by cnx_sort/
 qed.
 
-lemma cnx_abst: ∀h,g,a,G,L,W,T. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃W⦄ → ⦃G, L.ⓛW⦄ ⊢ 𝐍[h, g]⦃T⦄ →
-                ⦃G, L⦄ ⊢ 𝐍[h, g]⦃ⓛ{a}W.T⦄.
+lemma cnx_lref_free: ∀h,g,G,L,i. |L| ≤ i → ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃#i⦄.
+#h #g #G #L #i #Hi #X #H elim (cpx_inv_lref1 … H) -H // *
+#I #K #V1 #V2 #HLK lapply (drop_fwd_length_lt2 … HLK) -HLK
+#H elim (lt_refl_false i) /2 width=3 by lt_to_le_to_lt/
+qed.
+
+lemma cnx_lref_atom: ∀h,g,G,L,i. ⇩[i] L ≡ ⋆ → ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃#i⦄.
+#h #g #G #L #i #HL @cnx_lref_free >(drop_fwd_length … HL) -HL //
+qed.
+
+lemma cnx_abst: ∀h,g,a,G,L,W,T. ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃W⦄ → ⦃G, L.ⓛW⦄ ⊢ ➡[h, g] 𝐍⦃T⦄ →
+                ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃ⓛ{a}W.T⦄.
 #h #g #a #G #L #W #T #HW #HT #X #H
 elim (cpx_inv_abst1 … H) -H #W0 #T0 #HW0 #HT0 #H destruct
 >(HW … HW0) -W0 >(HT … HT0) -T0 //
 qed.
 
-lemma cnx_appl_simple: ∀h,g,G,L,V,T. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃V⦄ → ⦃G, L⦄ ⊢ 𝐍[h, g]⦃T⦄ → 𝐒⦃T⦄ →
-                       ⦃G, L⦄ ⊢ 𝐍[h, g]⦃ⓐV.T⦄.
+lemma cnx_appl_simple: ∀h,g,G,L,V,T. ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃V⦄ → ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃T⦄ → 𝐒⦃T⦄ →
+                       ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃ⓐV.T⦄.
 #h #g #G #L #V #T #HV #HT #HS #X #H
 elim (cpx_inv_appl1_simple … H) -H // #V0 #T0 #HV0 #HT0 #H destruct
 >(HV … HV0) -V0 >(HT … HT0) -T0 //
 qed.
 
-axiom cnx_dec: ∀h,g,G,L,T1. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃T1⦄ ∨
+axiom cnx_dec: ∀h,g,G,L,T1. ⦃G, L⦄ ⊢ ➡[h, g] 𝐍⦃T1⦄ ∨
                ∃∃T2. ⦃G, L⦄ ⊢ T1 ➡[h, g] T2 & (T1 = T2 → ⊥).