1 (**************************************************************************)
4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
10 (* \ / This file is distributed under the terms of the *)
11 (* v GNU General Public License Version 2 *)
13 (**************************************************************************)
15 include "basic_2/relocation/drops_drops.ma".
16 include "basic_2/static/frees.ma".
18 (* CONTEXT-SENSITIVE FREE VARIABLES *****************************************)
20 (* Advanced properties ******************************************************)
22 lemma frees_lref_atom: ∀b,L,i. ⬇*[b, 𝐔❴i❵] L ≡ ⋆ →
23 ∀f. 𝐈⦃f⦄ → L ⊢ 𝐅*⦃#i⦄ ≡ f.
24 #b #L elim L -L /2 width=1 by frees_atom/
26 [ #H lapply (drops_fwd_isid … H ?) -H // #H destruct
27 | /5 width=3 by frees_eq_repl_back, frees_lref, drops_inv_drop1, eq_push_inv_isid/
31 lemma frees_lref_pair: ∀f,K,V. K ⊢ 𝐅*⦃V⦄ ≡ f →
32 ∀i,I,L. ⬇*[i] L ≡ K.ⓑ{I}V → L ⊢ 𝐅*⦃#i⦄ ≡ ↑*[i] ⫯f.
33 #f #K #V #Hf #i elim i -i
34 [ #I #L #H lapply (drops_fwd_isid … H ?) -H /2 width=1 by frees_zero/
35 | #i #IH #I #L #H elim (drops_inv_succ … H) -H /3 width=2 by frees_lref/
39 lemma frees_sort_pushs: ∀f,K,s. K ⊢ 𝐅*⦃⋆s⦄ ≡ f →
40 ∀i,L. ⬇*[i] L ≡ K → L ⊢ 𝐅*⦃⋆s⦄ ≡ ↑*[i] f.
41 #f #K #s #Hf #i elim i -i
42 [ #L #H lapply (drops_fwd_isid … H ?) -H //
43 | #i #IH #L #H elim (drops_inv_succ … H) -H /3 width=1 by frees_sort/
47 lemma frees_lref_pushs: ∀f,K,j. K ⊢ 𝐅*⦃#j⦄ ≡ f →
48 ∀i,L. ⬇*[i] L ≡ K → L ⊢ 𝐅*⦃#(i+j)⦄ ≡ ↑*[i] f.
49 #f #K #j #Hf #i elim i -i
50 [ #L #H lapply (drops_fwd_isid … H ?) -H //
51 | #i #IH #L #H elim (drops_inv_succ … H) -H /3 width=1 by frees_lref/
55 lemma frees_gref_pushs: ∀f,K,l. K ⊢ 𝐅*⦃§l⦄ ≡ f →
56 ∀i,L. ⬇*[i] L ≡ K → L ⊢ 𝐅*⦃§l⦄ ≡ ↑*[i] f.
57 #f #K #l #Hf #i elim i -i
58 [ #L #H lapply (drops_fwd_isid … H ?) -H //
59 | #i #IH #L #H elim (drops_inv_succ … H) -H /3 width=1 by frees_gref/
63 (* Advanced inversion lemmas ************************************************)
65 lemma frees_inv_lref_drops: ∀i,f,L. L ⊢ 𝐅*⦃#i⦄ ≡ f →
66 (⬇*[Ⓕ, 𝐔❴i❵] L ≡ ⋆ ∧ 𝐈⦃f⦄) ∨
67 ∃∃g,I,K,V. K ⊢ 𝐅*⦃V⦄ ≡ g &
68 ⬇*[i] L ≡ K.ⓑ{I}V & f = ↑*[i] ⫯g.
70 [ #f #L #H elim (frees_inv_zero … H) -H *
71 /4 width=7 by ex3_4_intro, or_introl, or_intror, conj, drops_refl/
72 | #i #IH #f #L #H elim (frees_inv_lref … H) -H * /3 width=1 by or_introl, conj/
73 #g #I #K #V #Hg #H1 #H2 destruct
74 elim (IH … Hg) -IH -Hg *
75 [ /4 width=3 by or_introl, conj, isid_push, drops_drop/
76 | /4 width=7 by drops_drop, ex3_4_intro, or_intror/
81 (* Properties with generic slicing for local environments *******************)
83 lemma frees_lifts: ∀b,f1,K,T. K ⊢ 𝐅*⦃T⦄ ≡ f1 →
84 ∀f,L. ⬇*[b, f] L ≡ K → ∀U. ⬆*[f] T ≡ U →
85 ∀f2. f ~⊚ f1 ≡ f2 → L ⊢ 𝐅*⦃U⦄ ≡ f2.
86 #b #f1 #K #T #H lapply (frees_fwd_isfin … H) elim H -f1 -K -T
87 [ #f1 #I #Hf1 #_ #f #L #H1 #U #H2 #f2 #H3
88 lapply (coafter_isid_inv_dx … H3 … Hf1) -f1 #Hf2
89 elim (lifts_inv_atom1 … H2) -H2 *
90 /2 width=1 by frees_sort_gen, frees_gref_gen/
91 #i #j #Hij #H #H0 destruct
92 elim (drops_inv_atom2 … H1) -H1 #n #g #H1 #Hf
93 elim (after_at_fwd … Hij … Hf) -f #x #_ #Hj -g -i
94 lapply (at_inv_uni … Hj) -Hj #H destruct
95 /3 width=8 by frees_lref_atom, drops_trans/
96 | #f1 #I #K #V #s #_ #IH #Hf1 #f #L #H1 #U #H2 #f2 #H3
97 lapply (isfin_fwd_push … Hf1 ??) -Hf1 [3: |*: // ] #Hf1
98 lapply (lifts_inv_sort1 … H2) -H2 #H destruct
99 elim (drops_split_trans_pair2 … H1) -H1 [ |*: // ] #Y #W #HLY #HYK #_
100 elim (coafter_fwd_xpx_pushs … H3) [ |*: // ] #g2 #H2 destruct
101 lapply (coafter_tls_succ … H3 ??) -H3 [3: |*: // ] #H3
102 lapply (IH … HYK … H3) -IH -H3 -HYK [1,3: // | skip ]
103 /3 width=5 by drops_isuni_fwd_drop2, frees_sort_pushs/
104 | #f1 #I #K #V #_ #IH #Hf1 #f #L #H1 #U #H2 #f2 #H3
105 lapply (isfin_inv_next … Hf1 ??) -Hf1 [3: |*: // ] #Hf1
106 lapply (lifts_inv_lref1 … H2) -H2 * #j #Hf #H destruct
107 elim (drops_split_trans_pair2 … H1) -H1 [ |*: // ] #Y #W #HLY #HYK #HVW
108 elim (coafter_fwd_xnx_pushs … H3) [ |*: // ] #g2 #H2 destruct
109 lapply (coafter_tls_succ … H3 ??) -H3 [3: |*: // ]
110 <tls_S in ⊢ (???%→?); <tls_pushs <tl_next_rew <tl_next_rew #H3
111 lapply (IH … HYK … HVW … H3) -IH -H3 -HYK -HVW //
112 /2 width=5 by frees_lref_pair/
113 | #f1 #I #K #V #i #_ #IH #Hf1 #f #L #H1 #U #H2 #f2 #H3
114 lapply (isfin_fwd_push … Hf1 ??) -Hf1 [3: |*: // ] #Hf1
115 lapply (lifts_inv_lref1 … H2) -H2 * #x #Hf #H destruct
116 elim (at_inv_nxx … Hf) -Hf [ |*: // ] #j #Hf #H destruct
117 elim (drops_split_trans_pair2 … H1) -H1 [ |*: // ] #Y #W #HLY #HYK #_
118 elim (coafter_fwd_xpx_pushs … H3) [ |*: // ] #g2 #H2 destruct
119 lapply (coafter_tls_succ … H3 ??) -H3 [3: |*: // ] <tls_pushs #H3
120 lapply (drops_isuni_fwd_drop2 … HLY) -HLY // #HLY
121 lapply (IH … HYK … H3) -IH -H3 -HYK [4: |*: /2 width=2 by lifts_lref/ ]
122 >plus_S1 /2 width=3 by frees_lref_pushs/ (**) (* full auto fails *)
123 | #f1 #I #K #V #l #_ #IH #Hf1 #f #L #H1 #U #H2 #f2 #H3
124 lapply (isfin_fwd_push … Hf1 ??) -Hf1 [3: |*: // ] #Hf1
125 lapply (lifts_inv_gref1 … H2) -H2 #H destruct
126 elim (drops_split_trans_pair2 … H1) -H1 [ |*: // ] #Y #W #HLY #HYK #_
127 elim (coafter_fwd_xpx_pushs … H3) [ |*: // ] #g2 #H2 destruct
128 lapply (coafter_tls_succ … H3 ??) -H3 [3: |*: // ] #H3
129 lapply (IH … HYK … H3) -IH -H3 -HYK [1,3: // | skip ]
130 /3 width=5 by drops_isuni_fwd_drop2, frees_gref_pushs/
131 | #f1V #f1T #f1 #p #I #K #V #T #_ #_ #H1f1 #IHV #IHT #H2f1 #f #L #H1 #Y #H2 #f2 #H3
132 elim (sor_inv_isfin3 … H1f1) // #Hf1V #H
133 lapply (isfin_inv_tl … H) -H
134 elim (lifts_inv_bind1 … H2) -H2 #W #U #HVW #HTU #H destruct
135 elim (coafter_sor … H3 … H1f1) /2 width=5 by coafter_isfin2_fwd/ -H3 -H1f1 #f2V #f2T #Hf2V #H
136 elim (coafter_inv_tl1 … H) -H /4 width=5 by frees_bind, drops_skip/
137 | #f1V #f1T #f1 #I #K #V #T #_ #_ #H1f1 #IHV #IHT #H2f1 #f #L #H1 #Y #H2 #f2 #H3
138 elim (sor_inv_isfin3 … H1f1) //
139 elim (lifts_inv_flat1 … H2) -H2 #W #U #HVW #HTU #H destruct
140 elim (coafter_sor … H3 … H1f1)
141 /3 width=5 by coafter_isfin2_fwd, frees_flat/
145 (* Inversion lemmas with generic slicing for local environments *************)
147 lemma frees_inv_lifts: ∀b,f2,L,U. L ⊢ 𝐅*⦃U⦄ ≡ f2 →
148 ∀f,K. ⬇*[b, f] L ≡ K → ∀T. ⬆*[f] T ≡ U →
149 ∀f1. f ~⊚ f1 ≡ f2 → K ⊢ 𝐅*⦃T⦄ ≡ f1.
150 #b #f2 #L #U #H lapply (frees_fwd_isfin … H) elim H -f2 -L -U
151 [ #f2 #I #Hf2 #_ #f #K #H1 #T #H2 #f1 #H3
152 lapply (coafter_fwd_isid2 … H3 … Hf2) -H3 // -Hf2 #Hf1
153 elim (drops_inv_atom1 … H1) -H1 #H #_ destruct
154 elim (lifts_inv_atom2 … H2) -H2 * /2 width=3 by frees_atom/
155 | #f2 #I #L #W #s #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
156 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
157 lapply (lifts_inv_sort2 … H2) -H2 #H destruct
158 elim (coafter_inv_xxp … H3) -H3 [1,3: * |*: // ]
159 [ #g #g1 #Hf2 #H #H0 destruct
160 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
161 | #g #Hf2 #H destruct
162 lapply (drops_inv_drop1 … H1) -H1
163 ] /3 width=4 by frees_sort/
164 | #f2 #I #L #W #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
165 lapply (isfin_inv_next … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
166 elim (lifts_inv_lref2 … H2) -H2 #i #H2 #H destruct
167 lapply (at_inv_xxp … H2 ?) -H2 // * #g #H #H0 destruct
168 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #HVW #H destruct
169 elim (coafter_inv_pxn … H3) -H3 [ |*: // ] #g1 #Hf2 #H destruct
170 /3 width=4 by frees_zero/
171 | #f2 #I #L #W #j #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
172 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
173 elim (lifts_inv_lref2 … H2) -H2 #x #H2 #H destruct
174 elim (coafter_inv_xxp … H3) -H3 [1,3: * |*: // ]
175 [ #g #g1 #Hf2 #H #H0 destruct
176 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #HVW #H destruct
177 elim (at_inv_xpn … H2) -H2 [ |*: // ] #j #Hg #H destruct
178 | #g #Hf2 #H destruct
179 lapply (drops_inv_drop1 … H1) -H1
180 lapply (at_inv_xnn … H2 ????) -H2 [5: |*: // ]
181 ] /4 width=4 by lifts_lref, frees_lref/
182 | #f2 #I #L #W #l #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
183 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
184 lapply (lifts_inv_gref2 … H2) -H2 #H destruct
185 elim (coafter_inv_xxp … H3) -H3 [1,3: * |*: // ]
186 [ #g #g1 #Hf2 #H #H0 destruct
187 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
188 | #g #Hf2 #H destruct
189 lapply (drops_inv_drop1 … H1) -H1
190 ] /3 width=4 by frees_gref/
191 | #f2W #f2U #f2 #p #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #X #H2 #f1 #H3
192 elim (sor_inv_isfin3 … H1f2) // #H1f2W #H
193 lapply (isfin_inv_tl … H) -H
194 elim (lifts_inv_bind2 … H2) -H2 #V #T #HVW #HTU #H destruct
195 elim (coafter_inv_sor … H3 … H1f2) -H3 -H1f2 // #f1W #f1U #H2f2W #H
196 elim (coafter_inv_tl0 … H) -H /4 width=5 by frees_bind, drops_skip/
197 | #f2W #f2U #f2 #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #X #H2 #f1 #H3
198 elim (sor_inv_isfin3 … H1f2) //
199 elim (lifts_inv_flat2 … H2) -H2 #V #T #HVW #HTU #H destruct
200 elim (coafter_inv_sor … H3 … H1f2) -H3 -H1f2 /3 width=5 by frees_flat/
204 lemma frees_inv_drops: ∀f2,L,U. L ⊢ 𝐅*⦃U⦄ ≡ f2 →
205 ∀f,K. ⬇*[Ⓣ, f] L ≡ K → ∀f1. f ~⊚ f1 ≡ f2 →
206 ∃∃T. K ⊢ 𝐅*⦃T⦄ ≡ f1 & ⬆*[f] T ≡ U.
207 #f2 #L #U #H lapply (frees_fwd_isfin … H) elim H -f2 -L -U
208 [ #f2 #I #Hf2 #_ #f #K #H1 #f1 #H2
209 lapply (coafter_fwd_isid2 … H2 ??) -H2 // -Hf2 #Hf1
210 elim (drops_inv_atom1 … H1) -H1 #H #Hf destruct
211 /4 width=3 by frees_atom, lifts_refl, ex2_intro/
212 | #f2 #I #L #W #s #_ #IH #Hf2 #f #Y #H1 #f1 #H2
213 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
214 elim (coafter_inv_xxp … H2) -H2 [1,3: * |*: // ]
215 [ #g #g1 #Hf2 #H #H0 destruct
216 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
217 | #g #Hf2 #H destruct
218 lapply (drops_inv_drop1 … H1) -H1 #HLK
220 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
221 lapply (lifts_inv_sort2 … HX) -HX #H destruct
222 /3 width=3 by frees_sort, lifts_sort, ex2_intro/
223 | #f2 #I #L #W #_ #IH #Hf2 #f #Y #H1 #f1 #H2
224 lapply (isfin_inv_next … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
225 elim (coafter_inv_xxn … H2) -H2 [ |*: // ] #g #g1 #Hf2 #H0 #H destruct
226 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #HVW #H destruct
227 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
228 lapply (lifts_inj … HX … HVW) -W #H destruct
229 /3 width=3 by frees_zero, lifts_lref, ex2_intro/
230 | #f2 #I #L #W #j #_ #IH #Hf2 #f #Y #H1 #f1 #H2
231 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
232 elim (coafter_inv_xxp … H2) -H2 [1,3: * |*: // ]
233 [ #g #g1 #Hf2 #H #H0 destruct
234 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
235 | #g #Hf2 #H destruct
236 lapply (drops_inv_drop1 … H1) -H1 #HLK
238 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
239 elim (lifts_inv_lref2 … HX) -HX #i #Hij #H destruct
240 /4 width=7 by frees_lref, lifts_lref, at_S1, at_next, ex2_intro/
241 | #f2 #I #L #W #l #_ #IH #Hf2 #f #Y #H1 #f1 #H2
242 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
243 elim (coafter_inv_xxp … H2) -H2 [1,3: * |*: // ]
244 [ #g #g1 #Hf2 #H #H0 destruct
245 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
246 | #g #Hf2 #H destruct
247 lapply (drops_inv_drop1 … H1) -H1 #HLK
249 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
250 lapply (lifts_inv_gref2 … HX) -HX #H destruct
251 /3 width=3 by frees_gref, lifts_gref, ex2_intro/
252 | #f2W #f2U #f2 #p #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #f1 #H2
253 elim (sor_inv_isfin3 … H1f2) // #H1f2W #H
254 lapply (isfin_inv_tl … H) -H #H1f2U
255 elim (coafter_inv_sor … H2 … H1f2) -H2 -H1f2 // #f1W #f1U #H2f2W #H #Hf1
256 elim (coafter_inv_tl0 … H) -H #g1 #H2f2U #H destruct
257 elim (IHW … H1 … H2f2W) -IHW -H2f2W // -H1f2W #V #Hf1W #HVW
258 elim (IHU … H2f2U) -IHU -H2f2U
259 /3 width=5 by frees_bind, drops_skip, lifts_bind, ex2_intro/
260 | #f2W #f2U #f2 #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #f1 #H2
261 elim (sor_inv_isfin3 … H1f2) // #H1f2W #H1f2U
262 elim (coafter_inv_sor … H2 … H1f2) -H2 -H1f2 // #f1W #f1U #H2f2W #H2f2U #Hf1
263 elim (IHW … H1 … H2f2W) -IHW -H2f2W // -H1f2W
264 elim (IHU … H1 … H2f2U) -L -H2f2U
265 /3 width=5 by frees_flat, lifts_flat, ex2_intro/