first main property of drop closed

[helm.git] / matita / matita / lib / lambda-delta / substitution / lift_main.ma

diff --git a/matita/matita/lib/lambda-delta/substitution/lift_main.ma b/matita/matita/lib/lambda-delta/substitution/lift_main.ma
index ba74cf7b2507e8bd8d182ff19772354688c288d7..a41e49c5b86eea11ab3d1d0929b7445de2f31678 100644 (file)
--- a/matita/matita/lib/lambda-delta/substitution/lift_main.ma
+++ b/matita/matita/lib/lambda-delta/substitution/lift_main.ma
@@ -18,10 +18,10 @@ include "lambda-delta/substitution/lift_defs.ma".
 
 (* the main properies *******************************************************)
 
-theorem lift_div_le: ∀d1,e1,T1,T. ↑[d1, e1] T1 ≡ T →
-                     ∀d2,e2,T2. ↑[d2 + e1, e2] T2 ≡ T →
-                     d1 ≤ d2 →
-                     ∃∃T0. ↑[d1, e1] T0 ≡ T2 & ↑[d2, e2] T0 ≡ T1.
+lemma lift_div_le: ∀d1,e1,T1,T. ↑[d1, e1] T1 ≡ T →
+                   ∀d2,e2,T2. ↑[d2 + e1, e2] T2 ≡ T →
+                   d1 ≤ d2 →
+                   ∃∃T0. ↑[d1, e1] T0 ≡ T2 & ↑[d2, e2] T0 ≡ T1.
 #d1 #e1 #T1 #T #H elim H -H d1 e1 T1 T
 [ #k #d1 #e1 #d2 #e2 #T2 #Hk #Hd12
   lapply (lift_inv_sort2 … Hk) -Hk #Hk destruct -T2 /3/
@@ -48,9 +48,9 @@ theorem lift_div_le: ∀d1,e1,T1,T. ↑[d1, e1] T1 ≡ T →
 ]
 qed.
 
-theorem lift_free: ∀d1,e2,T1,T2. ↑[d1, e2] T1 ≡ T2 → ∀d2,e1.
-                                 d1 ≤ d2 → d2 ≤ d1 + e1 → e1 ≤ e2 →
-                                 ∃∃T. ↑[d1, e1] T1 ≡ T & ↑[d2, e2 - e1] T ≡ T2.
+lemma lift_free: ∀d1,e2,T1,T2. ↑[d1, e2] T1 ≡ T2 → ∀d2,e1.
+                               d1 ≤ d2 → d2 ≤ d1 + e1 → e1 ≤ e2 →
+                               ∃∃T. ↑[d1, e1] T1 ≡ T & ↑[d2, e2 - e1] T ≡ T2.
 #d1 #e2 #T1 #T2 #H elim H -H d1 e2 T1 T2
 [ /3/
 | #i #d1 #e2 #Hid1 #d2 #e1 #Hd12 #_ #_
@@ -67,10 +67,10 @@ theorem lift_free: ∀d1,e2,T1,T2. ↑[d1, e2] T1 ≡ T2 → ∀d2,e1.
 ]
 qed.
 
-theorem lift_trans_be: ∀d1,e1,T1,T. ↑[d1, e1] T1 ≡ T →
-                       ∀d2,e2,T2. ↑[d2, e2] T ≡ T2 →
-                       d1 ≤ d2 → d2 ≤ d1 + e1 → ↑[d1, e1 + e2] T1 ≡ T2.
-#d1 #e1 #T1 #T #H elim H -d1 e1 T1 T
+lemma lift_trans_be: ∀d1,e1,T1,T. ↑[d1, e1] T1 ≡ T →
+                     ∀d2,e2,T2. ↑[d2, e2] T ≡ T2 →
+                     d1 ≤ d2 → d2 ≤ d1 + e1 → ↑[d1, e1 + e2] T1 ≡ T2.
+#d1 #e1 #T1 #T #H elim H -H d1 e1 T1 T
 [ #k #d1 #e1 #d2 #e2 #T2 #HT2 #_ #_
   >(lift_inv_sort1 … HT2) -HT2 //
 | #i #d1 #e1 #Hid1 #d2 #e2 #T2 #HT2 #Hd12 #_
@@ -92,10 +92,52 @@ theorem lift_trans_be: ∀d1,e1,T1,T. ↑[d1, e1] T1 ≡ T →
 ]
 qed.
 
-axiom lift_trans_le: ∀d1,e1,T1,T. ↑[d1, e1] T1 ≡ T →
+lemma lift_trans_le: ∀d1,e1,T1,T. ↑[d1, e1] T1 ≡ T →
                      ∀d2,e2,T2. ↑[d2, e2] T ≡ T2 → d2 ≤ d1 →
                      ∃∃T0. ↑[d2, e2] T1 ≡ T0 & ↑[d1 + e2, e1] T0 ≡ T2.
+#d1 #e1 #T1 #T #H elim H -H d1 e1 T1 T
+[ #k #d1 #e1 #d2 #e2 #X #HX #_
+  >(lift_inv_sort1 … HX) -HX /2/
+| #i #d1 #e1 #Hid1 #d2 #e2 #X #HX #_
+  lapply (lt_to_le_to_lt … (d1+e2) Hid1 ?) // #Hie2
+  elim (lift_inv_lref1 … HX) -HX * #Hid2 #HX destruct -X /4/
+| #i #d1 #e1 #Hid1 #d2 #e2 #X #HX #Hd21
+  lapply (transitive_le … Hd21 Hid1) -Hd21 #Hid2
+  lapply (lift_inv_lref1_ge … HX ?) -HX /2/ #HX destruct -X;
+  >plus_plus_comm_23 /4/
+| #I #V1 #V2 #T1 #T2 #d1 #e1 #_ #_ #IHV12 #IHT12 #d2 #e2 #X #HX #Hd21
+  elim (lift_inv_bind1 … HX) -HX #V0 #T0 #HV20 #HT20 #HX destruct -X;
+  elim (IHV12 … HV20 ?) -IHV12 HV20 //
+  elim (IHT12 … HT20 ?) -IHT12 HT20 /3 width=5/
+| #I #V1 #V2 #T1 #T2 #d1 #e1 #_ #_ #IHV12 #IHT12 #d2 #e2 #X #HX #Hd21
+  elim (lift_inv_flat1 … HX) -HX #V0 #T0 #HV20 #HT20 #HX destruct -X;
+  elim (IHV12 … HV20 ?) -IHV12 HV20 //
+  elim (IHT12 … HT20 ?) -IHT12 HT20 /3 width=5/
+]
+qed.
 
-axiom lift_trans_ge: ∀d1,e1,T1,T. ↑[d1, e1] T1 ≡ T →
+lemma lift_trans_ge: ∀d1,e1,T1,T. ↑[d1, e1] T1 ≡ T →
                      ∀d2,e2,T2. ↑[d2, e2] T ≡ T2 → d1 + e1 ≤ d2 →
                      ∃∃T0. ↑[d2 - e1, e2] T1 ≡ T0 & ↑[d1, e1] T0 ≡ T2.
+#d1 #e1 #T1 #T #H elim H -H d1 e1 T1 T
+[ #k #d1 #e1 #d2 #e2 #X #HX #_
+  >(lift_inv_sort1 … HX) -HX /2/
+| #i #d1 #e1 #Hid1 #d2 #e2 #X #HX #Hded
+  lapply (lt_to_le_to_lt … (d1+e1) Hid1 ?) // #Hid1e
+  lapply (lt_to_le_to_lt … (d2-e1) Hid1 ?) /2/ #Hid2e
+  lapply (lt_to_le_to_lt … Hid1e Hded) -Hid1e Hded #Hid2
+  lapply (lift_inv_lref1_lt … HX ?) -HX // #HX destruct -X /3/
+| #i #d1 #e1 #Hid1 #d2 #e2 #X #HX #_
+  elim (lift_inv_lref1 … HX) -HX * #Hied #HX destruct -X;
+  [2: >plus_plus_comm_23] /4/
+| #I #V1 #V2 #T1 #T2 #d1 #e1 #_ #_ #IHV12 #IHT12 #d2 #e2 #X #HX #Hded
+  elim (lift_inv_bind1 … HX) -HX #V0 #T0 #HV20 #HT20 #HX destruct -X;
+  elim (IHV12 … HV20 ?) -IHV12 HV20 //
+  elim (IHT12 … HT20 ?) -IHT12 HT20 /2/ #T
+  <plus_minus /3 width=5/
+| #I #V1 #V2 #T1 #T2 #d1 #e1 #_ #_ #IHV12 #IHT12 #d2 #e2 #X #HX #Hded
+  elim (lift_inv_flat1 … HX) -HX #V0 #T0 #HV20 #HT20 #HX destruct -X;
+  elim (IHV12 … HV20 ?) -IHV12 HV20 //
+  elim (IHT12 … HT20 ?) -IHT12 HT20 /3 width=5/
+]
+qed.