(* Properties on append for local environments ******************************)
-fact drop_O1_append_sn_le_aux: ∀L1,L2,s,d,e. ⬇[s, d, e] L1 ≡ L2 →
- d = 0 → e ≤ |L1| →
- ∀L. ⬇[s, 0, e] L @@ L1 ≡ L @@ L2.
-#L1 #L2 #s #d #e #H elim H -L1 -L2 -d -e normalize
+fact drop_O1_append_sn_le_aux: ∀L1,L2,s,l,m. ⬇[s, l, m] L1 ≡ L2 →
+ l = 0 → m ≤ |L1| →
+ ∀L. ⬇[s, 0, m] L @@ L1 ≡ L @@ L2.
+#L1 #L2 #s #l #m #H elim H -L1 -L2 -l -m normalize
[2,3,4: /4 width=1 by drop_skip_lt, drop_drop, arith_b1, lt_minus_to_plus_r, monotonic_pred/ ]
-#d #e #_ #_ #H <(le_n_O_to_eq … H) -H //
+#l #m #_ #_ #H <(le_n_O_to_eq … H) -H //
qed-.
-lemma drop_O1_append_sn_le: ∀L1,L2,s,e. ⬇[s, 0, e] L1 ≡ L2 → e ≤ |L1| →
- ∀L. ⬇[s, 0, e] L @@ L1 ≡ L @@ L2.
+lemma drop_O1_append_sn_le: ∀L1,L2,s,m. ⬇[s, 0, m] L1 ≡ L2 → m ≤ |L1| →
+ ∀L. ⬇[s, 0, m] L @@ L1 ≡ L @@ L2.
/2 width=3 by drop_O1_append_sn_le_aux/ qed.
(* Inversion lemmas on append for local environments ************************)
-lemma drop_O1_inv_append1_ge: ∀K,L1,L2,s,e. ⬇[s, 0, e] L1 @@ L2 ≡ K →
- |L2| ≤ e → ⬇[s, 0, e - |L2|] L1 ≡ K.
+lemma drop_O1_inv_append1_ge: ∀K,L1,L2,s,m. ⬇[s, 0, m] L1 @@ L2 ≡ K →
+ |L2| ≤ m → ⬇[s, 0, m - |L2|] L1 ≡ K.
#K #L1 #L2 elim L2 -L2 normalize //
-#L2 #I #V #IHL2 #s #e #H #H1e
-elim (drop_inv_O1_pair1 … H) -H * #H2e #HL12 destruct
-[ lapply (le_n_O_to_eq … H1e) -H1e -IHL2
+#L2 #I #V #IHL2 #s #m #H #H1m
+elim (drop_inv_O1_pair1 … H) -H * #H2m #HL12 destruct
+[ lapply (le_n_O_to_eq … H1m) -H1m -IHL2
>commutative_plus normalize #H destruct
| <minus_plus >minus_minus_comm /3 width=1 by monotonic_pred/
]
qed-.
-lemma drop_O1_inv_append1_le: ∀K,L1,L2,s,e. ⬇[s, 0, e] L1 @@ L2 ≡ K → e ≤ |L2| →
- ∀K2. ⬇[s, 0, e] L2 ≡ K2 → K = L1 @@ K2.
+lemma drop_O1_inv_append1_le: ∀K,L1,L2,s,m. ⬇[s, 0, m] L1 @@ L2 ≡ K → m ≤ |L2| →
+ ∀K2. ⬇[s, 0, m] L2 ≡ K2 → K = L1 @@ K2.
#K #L1 #L2 elim L2 -L2 normalize
-[ #s #e #H1 #H2 #K2 #H3 lapply (le_n_O_to_eq … H2) -H2
+[ #s #m #H1 #H2 #K2 #H3 lapply (le_n_O_to_eq … H2) -H2
#H2 elim (drop_inv_atom1 … H3) -H3 #H3 #_ destruct
>(drop_inv_O2 … H1) -H1 //
-| #L2 #I #V #IHL2 #s #e @(nat_ind_plus … e) -e [ -IHL2 ]
+| #L2 #I #V #IHL2 #s #m @(nat_ind_plus … m) -m [ -IHL2 ]
[ #H1 #_ #K2 #H2
lapply (drop_inv_O2 … H1) -H1 #H1
lapply (drop_inv_O2 … H2) -H2 #H2 destruct //