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 "ground_2/relocation/rtmap_pushs.ma".
16 include "ground_2/relocation/rtmap_coafter.ma".
17 include "basic_2/relocation/drops_drops.ma".
18 include "basic_2/static/frees.ma".
20 (* CONTEXT-SENSITIVE FREE VARIABLES *****************************************)
22 (* Advanced properties ******************************************************)
24 lemma frees_lref_atom: ∀b,L,i. ⬇*[b, 𝐔❴i❵] L ≡ ⋆ →
25 ∀f. 𝐈⦃f⦄ → L ⊢ 𝐅*⦃#i⦄ ≡ f.
26 #b #L elim L -L /2 width=1 by frees_atom/
28 [ #H lapply (drops_fwd_isid … H ?) -H // #H destruct
29 | /5 width=3 by frees_eq_repl_back, frees_lref, drops_inv_drop1, eq_push_inv_isid/
33 lemma frees_lref_pair: ∀f,K,V. K ⊢ 𝐅*⦃V⦄ ≡ f →
34 ∀i,I,L. ⬇*[i] L ≡ K.ⓑ{I}V → L ⊢ 𝐅*⦃#i⦄ ≡ ↑*[i] ⫯f.
35 #f #K #V #Hf #i elim i -i
36 [ #I #L #H lapply (drops_fwd_isid … H ?) -H /2 width=1 by frees_zero/
37 | #i #IH #I #L #H elim (drops_inv_succ … H) -H /3 width=2 by frees_lref/
41 (* Advanced inversion lemmas ************************************************)
43 lemma frees_inv_lref_drops: ∀i,f,L. L ⊢ 𝐅*⦃#i⦄ ≡ f →
44 (⬇*[Ⓕ, 𝐔❴i❵] L ≡ ⋆ ∧ 𝐈⦃f⦄) ∨
45 ∃∃g,I,K,V. K ⊢ 𝐅*⦃V⦄ ≡ g &
46 ⬇*[i] L ≡ K.ⓑ{I}V & f = ↑*[i] ⫯g.
48 [ #f #L #H elim (frees_inv_zero … H) -H *
49 /4 width=7 by ex3_4_intro, or_introl, or_intror, conj, drops_refl/
50 | #i #IH #f #L #H elim (frees_inv_lref … H) -H * /3 width=1 by or_introl, conj/
51 #g #I #K #V #Hg #H1 #H2 destruct
52 elim (IH … Hg) -IH -Hg *
53 [ /4 width=3 by or_introl, conj, isid_push, drops_drop/
54 | /4 width=7 by drops_drop, ex3_4_intro, or_intror/
59 (* Properties with generic slicing for local environments *******************)
61 axiom coafter_inv_xpx: ∀g2,f1,g. g2 ~⊚ ↑f1 ≡ g → ∀n. @⦃0, g2⦄ ≡ n →
62 ∃∃f2,f. f2 ~⊚ f1 ≡ f & ⫱*[n]g2 = ↑f2 & ⫱*[n]g = ↑f.
64 #g2 #g1 #g #Hg #n #Hg2
65 lapply (coafter_tls … Hg2 … Hg) -Hg #Hg
66 lapply (at_pxx_tls … Hg2) -Hg2 #H
67 elim (at_inv_pxp … H) -H [ |*: // ] #f2 #H2
68 elim (coafter_inv_pxx … Hg … H2) -Hg * #f1 #f #Hf #H1 #H0 destruct
69 <tls_rew_S <tls_rew_S <H2 <H0 -g2 -g -n //
73 lemma coafter_tls_succ: ∀g2,g1,g. g2 ~⊚ g1 ≡ g →
74 ∀n. @⦃0, g2⦄ ≡ n → ⫱*[⫯n]g2 ~⊚ ⫱g1 ≡ ⫱*[⫯n]g.
75 #g2 #g1 #g #Hg #n #Hg2
76 lapply (coafter_tls … Hg2 … Hg) -Hg #Hg
77 lapply (at_pxx_tls … Hg2) -Hg2 #H
78 elim (at_inv_pxp … H) -H [ |*: // ] #f2 #H2
79 elim (coafter_inv_pxx … Hg … H2) -Hg * #f1 #f #Hf #H1 #H0 destruct
80 <tls_rew_S <tls_rew_S <H2 <H0 -g2 -g -n //
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 lapply (at_total 0 f) #H
100 elim (drops_split_trans … H1) -H1
101 [5: @(after_uni_dx … H) /2 width=1 by after_isid_dx/ |2,3: skip
102 |4: // ] #X #HLX #HXK
103 lapply (drops_inv_tls_at … H … HXK) -HXK #HXK
104 elim (drops_inv_skip2 … HXK) -HXK
105 #Y #W #HYK #HVW #H0 destruct
108 elim (coafter_inv_xpx … H3 ??) -H3 [ |*: // ] #g2 #g #Hg #H2 #H0
109 lapply (IH … Hg) -IH -Hg
115 lapply (coafter_tls_succ … H3 ??) -H3 [3: |*: // ] #H3
116 lapply (IH … HYK … H3) -IH -H3 -HYK
118 #H lapply (frees_sort … H)
123 elim (coafter_inv_xxp … H3) -H3 [1,3: * |*: // ]
124 [ #g #g1 #Hf2 #H #H0 destruct
125 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
126 | #g #Hf2 #H destruct
127 lapply (drops_inv_drop1 … H1) -H1
128 ] /3 width=4 by frees_sort/
133 | #f1V #f1T #f1 #p #I #K #V #T #_ #_ #H1f1 #IHV #IHT #H2f1 #f #L #H1 #Y #H2 #f2 #H3
134 elim (sor_inv_isfin3 … H1f1) // #Hf1V #H
135 lapply (isfin_inv_tl … H) -H
136 elim (lifts_inv_bind1 … H2) -H2 #W #U #HVW #HTU #H destruct
137 elim (coafter_sor … H3 … H1f1) /2 width=5 by coafter_isfin2_fwd/ -H3 -H1f1 #f2V #f2T #Hf2V #H
138 elim (coafter_inv_tl1 … H) -H /4 width=5 by frees_bind, drops_skip/
139 | #f1V #f1T #f1 #I #K #V #T #_ #_ #H1f1 #IHV #IHT #H2f1 #f #L #H1 #Y #H2 #f2 #H3
140 elim (sor_inv_isfin3 … H1f1) //
141 elim (lifts_inv_flat1 … H2) -H2 #W #U #HVW #HTU #H destruct
142 elim (coafter_sor … H3 … H1f1)
143 /3 width=5 by coafter_isfin2_fwd, frees_flat/
146 (* Inversion lemmas with generic slicing for local environments *************)
148 lemma frees_inv_lifts: ∀b,f2,L,U. L ⊢ 𝐅*⦃U⦄ ≡ f2 →
149 ∀f,K. ⬇*[b, f] L ≡ K → ∀T. ⬆*[f] T ≡ U →
150 ∀f1. f ~⊚ f1 ≡ f2 → K ⊢ 𝐅*⦃T⦄ ≡ f1.
151 #b #f2 #L #U #H lapply (frees_fwd_isfin … H) elim H -f2 -L -U
152 [ #f2 #I #Hf2 #_ #f #K #H1 #T #H2 #f1 #H3
153 lapply (coafter_fwd_isid2 … H3 … Hf2) -H3 // -Hf2 #Hf1
154 elim (drops_inv_atom1 … H1) -H1 #H #_ destruct
155 elim (lifts_inv_atom2 … H2) -H2 * /2 width=3 by frees_atom/
156 | #f2 #I #L #W #s #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
157 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
158 lapply (lifts_inv_sort2 … H2) -H2 #H destruct
159 elim (coafter_inv_xxp … H3) -H3 [1,3: * |*: // ]
160 [ #g #g1 #Hf2 #H #H0 destruct
161 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
162 | #g #Hf2 #H destruct
163 lapply (drops_inv_drop1 … H1) -H1
164 ] /3 width=4 by frees_sort/
165 | #f2 #I #L #W #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
166 lapply (isfin_inv_next … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
167 elim (lifts_inv_lref2 … H2) -H2 #i #H2 #H destruct
168 lapply (at_inv_xxp … H2 ?) -H2 // * #g #H #H0 destruct
169 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #HVW #H destruct
170 elim (coafter_inv_pxn … H3) -H3 [ |*: // ] #g1 #Hf2 #H destruct
171 /3 width=4 by frees_zero/
172 | #f2 #I #L #W #j #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
173 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
174 elim (lifts_inv_lref2 … H2) -H2 #x #H2 #H destruct
175 elim (coafter_inv_xxp … H3) -H3 [1,3: * |*: // ]
176 [ #g #g1 #Hf2 #H #H0 destruct
177 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #HVW #H destruct
178 elim (at_inv_xpn … H2) -H2 [ |*: // ] #j #Hg #H destruct
179 | #g #Hf2 #H destruct
180 lapply (drops_inv_drop1 … H1) -H1
181 lapply (at_inv_xnn … H2 ????) -H2 [5: |*: // ]
182 ] /4 width=4 by lifts_lref, frees_lref/
183 | #f2 #I #L #W #l #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
184 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
185 lapply (lifts_inv_gref2 … H2) -H2 #H destruct
186 elim (coafter_inv_xxp … H3) -H3 [1,3: * |*: // ]
187 [ #g #g1 #Hf2 #H #H0 destruct
188 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
189 | #g #Hf2 #H destruct
190 lapply (drops_inv_drop1 … H1) -H1
191 ] /3 width=4 by frees_gref/
192 | #f2W #f2U #f2 #p #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #X #H2 #f1 #H3
193 elim (sor_inv_isfin3 … H1f2) // #H1f2W #H
194 lapply (isfin_inv_tl … H) -H
195 elim (lifts_inv_bind2 … H2) -H2 #V #T #HVW #HTU #H destruct
196 elim (coafter_inv_sor … H3 … H1f2) -H3 -H1f2 // #f1W #f1U #H2f2W #H
197 elim (coafter_inv_tl0 … H) -H /4 width=5 by frees_bind, drops_skip/
198 | #f2W #f2U #f2 #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #X #H2 #f1 #H3
199 elim (sor_inv_isfin3 … H1f2) //
200 elim (lifts_inv_flat2 … H2) -H2 #V #T #HVW #HTU #H destruct
201 elim (coafter_inv_sor … H3 … H1f2) -H3 -H1f2 /3 width=5 by frees_flat/
205 lemma frees_inv_drops: ∀f2,L,U. L ⊢ 𝐅*⦃U⦄ ≡ f2 →
206 ∀f,K. ⬇*[Ⓣ, f] L ≡ K → ∀f1. f ~⊚ f1 ≡ f2 →
207 ∃∃T. K ⊢ 𝐅*⦃T⦄ ≡ f1 & ⬆*[f] T ≡ U.
208 #f2 #L #U #H lapply (frees_fwd_isfin … H) elim H -f2 -L -U
209 [ #f2 #I #Hf2 #_ #f #K #H1 #f1 #H2
210 lapply (coafter_fwd_isid2 … H2 ??) -H2 // -Hf2 #Hf1
211 elim (drops_inv_atom1 … H1) -H1 #H #Hf destruct
212 /4 width=3 by frees_atom, lifts_refl, ex2_intro/
213 | #f2 #I #L #W #s #_ #IH #Hf2 #f #Y #H1 #f1 #H2
214 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
215 elim (coafter_inv_xxp … H2) -H2 [1,3: * |*: // ]
216 [ #g #g1 #Hf2 #H #H0 destruct
217 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
218 | #g #Hf2 #H destruct
219 lapply (drops_inv_drop1 … H1) -H1 #HLK
221 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
222 lapply (lifts_inv_sort2 … HX) -HX #H destruct
223 /3 width=3 by frees_sort, lifts_sort, ex2_intro/
224 | #f2 #I #L #W #_ #IH #Hf2 #f #Y #H1 #f1 #H2
225 lapply (isfin_inv_next … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
226 elim (coafter_inv_xxn … H2) -H2 [ |*: // ] #g #g1 #Hf2 #H0 #H destruct
227 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #HVW #H destruct
228 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
229 lapply (lifts_inj … HX … HVW) -W #H destruct
230 /3 width=3 by frees_zero, lifts_lref, ex2_intro/
231 | #f2 #I #L #W #j #_ #IH #Hf2 #f #Y #H1 #f1 #H2
232 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
233 elim (coafter_inv_xxp … H2) -H2 [1,3: * |*: // ]
234 [ #g #g1 #Hf2 #H #H0 destruct
235 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
236 | #g #Hf2 #H destruct
237 lapply (drops_inv_drop1 … H1) -H1 #HLK
239 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
240 elim (lifts_inv_lref2 … HX) -HX #i #Hij #H destruct
241 /4 width=7 by frees_lref, lifts_lref, at_S1, at_next, ex2_intro/
242 | #f2 #I #L #W #l #_ #IH #Hf2 #f #Y #H1 #f1 #H2
243 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
244 elim (coafter_inv_xxp … H2) -H2 [1,3: * |*: // ]
245 [ #g #g1 #Hf2 #H #H0 destruct
246 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
247 | #g #Hf2 #H destruct
248 lapply (drops_inv_drop1 … H1) -H1 #HLK
250 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
251 lapply (lifts_inv_gref2 … HX) -HX #H destruct
252 /3 width=3 by frees_gref, lifts_gref, ex2_intro/
253 | #f2W #f2U #f2 #p #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #f1 #H2
254 elim (sor_inv_isfin3 … H1f2) // #H1f2W #H
255 lapply (isfin_inv_tl … H) -H #H1f2U
256 elim (coafter_inv_sor … H2 … H1f2) -H2 -H1f2 // #f1W #f1U #H2f2W #H #Hf1
257 elim (coafter_inv_tl0 … H) -H #g1 #H2f2U #H destruct
258 elim (IHW … H1 … H2f2W) -IHW -H2f2W // -H1f2W #V #Hf1W #HVW
259 elim (IHU … H2f2U) -IHU -H2f2U
260 /3 width=5 by frees_bind, drops_skip, lifts_bind, ex2_intro/
261 | #f2W #f2U #f2 #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #f1 #H2
262 elim (sor_inv_isfin3 … H1f2) // #H1f2W #H1f2U
263 elim (coafter_inv_sor … H2 … H1f2) -H2 -H1f2 // #f1W #f1U #H2f2W #H2f2U #Hf1
264 elim (IHW … H1 … H2f2W) -IHW -H2f2W // -H1f2W
265 elim (IHU … H1 … H2f2U) -L -H2f2U
266 /3 width=5 by frees_flat, lifts_flat, ex2_intro/