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/nstream_coafter.ma".
16 include "basic_2/relocation/drops_drops.ma".
17 include "basic_2/static/frees_frees.ma".
19 (* CONTEXT-SENSITIVE FREE VARIABLES *****************************************)
21 (* Advanced properties ******************************************************)
23 lemma frees_lref_atom: ∀b,L,i. ⬇*[b, 𝐔❴i❵] L ≡ ⋆ →
24 ∀f. 𝐈⦃f⦄ → L ⊢ 𝐅*⦃#i⦄ ≡ f.
25 #b #L elim L -L /2 width=1 by frees_atom/
27 [ #H lapply (drops_fwd_isid … H ?) -H // #H destruct
28 | /5 width=3 by frees_eq_repl_back, frees_lref, drops_inv_drop1, eq_push_inv_isid/
32 lemma frees_lref_pair: ∀f,K,V. K ⊢ 𝐅*⦃V⦄ ≡ f →
33 ∀i,I,L. ⬇*[i] L ≡ K.ⓑ{I}V → L ⊢ 𝐅*⦃#i⦄ ≡ ↑*[i] ⫯f.
34 #f #K #V #Hf #i elim i -i
35 [ #I #L #H lapply (drops_fwd_isid … H ?) -H /2 width=1 by frees_zero/
36 | #i #IH #I #L #H elim (drops_inv_succ … H) -H /3 width=2 by frees_lref/
40 lemma frees_sort_pushs: ∀f,K,s. K ⊢ 𝐅*⦃⋆s⦄ ≡ f →
41 ∀i,L. ⬇*[i] L ≡ K → L ⊢ 𝐅*⦃⋆s⦄ ≡ ↑*[i] f.
42 #f #K #s #Hf #i elim i -i
43 [ #L #H lapply (drops_fwd_isid … H ?) -H //
44 | #i #IH #L #H elim (drops_inv_succ … H) -H /3 width=1 by frees_sort/
48 lemma frees_lref_pushs: ∀f,K,j. K ⊢ 𝐅*⦃#j⦄ ≡ f →
49 ∀i,L. ⬇*[i] L ≡ K → L ⊢ 𝐅*⦃#(i+j)⦄ ≡ ↑*[i] f.
50 #f #K #j #Hf #i elim i -i
51 [ #L #H lapply (drops_fwd_isid … H ?) -H //
52 | #i #IH #L #H elim (drops_inv_succ … H) -H
53 #I #Y #V #HYK #H destruct /3 width=1 by frees_lref/
57 lemma frees_gref_pushs: ∀f,K,l. K ⊢ 𝐅*⦃§l⦄ ≡ f →
58 ∀i,L. ⬇*[i] L ≡ K → L ⊢ 𝐅*⦃§l⦄ ≡ ↑*[i] f.
59 #f #K #l #Hf #i elim i -i
60 [ #L #H lapply (drops_fwd_isid … H ?) -H //
61 | #i #IH #L #H elim (drops_inv_succ … H) -H /3 width=1 by frees_gref/
65 (* Advanced inversion lemmas ************************************************)
67 lemma frees_inv_lref_drops: ∀i,f,L. L ⊢ 𝐅*⦃#i⦄ ≡ f →
68 (⬇*[Ⓕ, 𝐔❴i❵] L ≡ ⋆ ∧ 𝐈⦃f⦄) ∨
69 ∃∃g,I,K,V. K ⊢ 𝐅*⦃V⦄ ≡ g &
70 ⬇*[i] L ≡ K.ⓑ{I}V & f = ↑*[i] ⫯g.
72 [ #f #L #H elim (frees_inv_zero … H) -H *
73 /4 width=7 by ex3_4_intro, or_introl, or_intror, conj, drops_refl/
74 | #i #IH #f #L #H elim (frees_inv_lref … H) -H * /3 width=1 by or_introl, conj/
75 #g #I #K #V #Hg #H1 #H2 destruct
76 elim (IH … Hg) -IH -Hg *
77 [ /4 width=3 by or_introl, conj, isid_push, drops_drop/
78 | /4 width=7 by drops_drop, ex3_4_intro, or_intror/
83 (* Properties with generic slicing for local environments *******************)
85 lemma frees_lifts: ∀b,f1,K,T. K ⊢ 𝐅*⦃T⦄ ≡ f1 →
86 ∀f,L. ⬇*[b, f] L ≡ K → ∀U. ⬆*[f] T ≡ U →
87 ∀f2. f ~⊚ f1 ≡ f2 → L ⊢ 𝐅*⦃U⦄ ≡ f2.
88 #b #f1 #K #T #H lapply (frees_fwd_isfin … H) elim H -f1 -K -T
89 [ #f1 #I #Hf1 #_ #f #L #H1 #U #H2 #f2 #H3
90 lapply (coafter_isid_inv_dx … H3 … Hf1) -f1 #Hf2
91 elim (lifts_inv_atom1 … H2) -H2 *
92 /2 width=1 by frees_sort_gen, frees_gref_gen/
93 #i #j #Hij #H #H0 destruct
94 elim (drops_inv_atom2 … H1) -H1 #n #g #H1 #Hf
95 elim (after_at_fwd … Hij … Hf) -f #x #_ #Hj -g -i
96 lapply (at_inv_uni … Hj) -Hj #H destruct
97 /3 width=8 by frees_lref_atom, drops_trans/
98 | #f1 #I #K #V #s #_ #IH #Hf1 #f #L #H1 #U #H2 #f2 #H3
99 lapply (isfin_fwd_push … Hf1 ??) -Hf1 [3: |*: // ] #Hf1
100 lapply (lifts_inv_sort1 … H2) -H2 #H destruct
101 elim (drops_split_trans_pair2 … H1) -H1 [ |*: // ] #Y #W #HLY #HYK #_
102 elim (coafter_fwd_xpx_pushs … H3) [ |*: // ] #g2 #H2 destruct
103 lapply (coafter_tls_succ … H3 ??) -H3 [3: |*: // ] #H3
104 lapply (IH … HYK … H3) -IH -H3 -HYK [1,3: // | skip ]
105 /3 width=5 by drops_isuni_fwd_drop2, frees_sort_pushs/
106 | #f1 #I #K #V #_ #IH #Hf1 #f #L #H1 #U #H2 #f2 #H3
107 lapply (isfin_inv_next … Hf1 ??) -Hf1 [3: |*: // ] #Hf1
108 lapply (lifts_inv_lref1 … H2) -H2 * #j #Hf #H destruct
109 elim (drops_split_trans_pair2 … H1) -H1 [ |*: // ] #Y #W #HLY #HYK #HVW
110 elim (coafter_fwd_xnx_pushs … H3) [ |*: // ] #g2 #H2 destruct
111 lapply (coafter_tls_succ … H3 ??) -H3 [3: |*: // ]
112 <tls_S in ⊢ (???%→?); <tls_pushs <tl_next_rew <tl_next_rew #H3
113 lapply (IH … HYK … HVW … H3) -IH -H3 -HYK -HVW //
114 /2 width=5 by frees_lref_pair/
115 | #f1 #I #K #V #i #_ #IH #Hf1 #f #L #H1 #U #H2 #f2 #H3
116 lapply (isfin_fwd_push … Hf1 ??) -Hf1 [3: |*: // ] #Hf1
117 lapply (lifts_inv_lref1 … H2) -H2 * #x #Hf #H destruct
118 elim (at_inv_nxx … Hf) -Hf [ |*: // ] #j #Hf #H destruct
119 elim (drops_split_trans_pair2 … H1) -H1 [ |*: // ] #Y #W #HLY #HYK #_
120 elim (coafter_fwd_xpx_pushs … H3) [ |*: // ] #g2 #H2 destruct
121 lapply (coafter_tls_succ … H3 ??) -H3 [3: |*: // ] <tls_pushs #H3
122 lapply (drops_isuni_fwd_drop2 … HLY) -HLY // #HLY
123 lapply (IH … HYK … H3) -IH -H3 -HYK [4: |*: /2 width=2 by lifts_lref/ ]
124 >plus_S1 /2 width=3 by frees_lref_pushs/ (**) (* full auto fails *)
125 | #f1 #I #K #V #l #_ #IH #Hf1 #f #L #H1 #U #H2 #f2 #H3
126 lapply (isfin_fwd_push … Hf1 ??) -Hf1 [3: |*: // ] #Hf1
127 lapply (lifts_inv_gref1 … H2) -H2 #H destruct
128 elim (drops_split_trans_pair2 … H1) -H1 [ |*: // ] #Y #W #HLY #HYK #_
129 elim (coafter_fwd_xpx_pushs … H3) [ |*: // ] #g2 #H2 destruct
130 lapply (coafter_tls_succ … H3 ??) -H3 [3: |*: // ] #H3
131 lapply (IH … HYK … H3) -IH -H3 -HYK [1,3: // | skip ]
132 /3 width=5 by drops_isuni_fwd_drop2, frees_gref_pushs/
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/
147 (* Forward lemmas with generic slicing for local environments ***************)
149 lemma frees_fwd_coafter: ∀b,f2,L,U. L ⊢ 𝐅*⦃U⦄ ≡ f2 →
150 ∀f,K. ⬇*[b, f] L ≡ K → ∀T. ⬆*[f] T ≡ U →
151 ∀f1. K ⊢ 𝐅*⦃T⦄ ≡ f1 → f ~⊚ f1 ≡ f2.
152 /4 width=11 by frees_lifts, frees_mono, coafter_eq_repl_back0/ qed-.
154 (* Inversion lemmas with generic slicing for local environments *************)
156 lemma frees_inv_lifts: ∀b,f2,L,U. L ⊢ 𝐅*⦃U⦄ ≡ f2 →
157 ∀f,K. ⬇*[b, f] L ≡ K → ∀T. ⬆*[f] T ≡ U →
158 ∀f1. f ~⊚ f1 ≡ f2 → K ⊢ 𝐅*⦃T⦄ ≡ f1.
159 #b #f2 #L #U #H lapply (frees_fwd_isfin … H) elim H -f2 -L -U
160 [ #f2 #I #Hf2 #_ #f #K #H1 #T #H2 #f1 #H3
161 lapply (coafter_fwd_isid2 … H3 … Hf2) -H3 // -Hf2 #Hf1
162 elim (drops_inv_atom1 … H1) -H1 #H #_ destruct
163 elim (lifts_inv_atom2 … H2) -H2 * /2 width=3 by frees_atom/
164 | #f2 #I #L #W #s #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
165 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
166 lapply (lifts_inv_sort2 … H2) -H2 #H destruct
167 elim (coafter_inv_xxp … H3) -H3 [1,3: * |*: // ]
168 [ #g #g1 #Hf2 #H #H0 destruct
169 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
170 | #g #Hf2 #H destruct
171 lapply (drops_inv_drop1 … H1) -H1
172 ] /3 width=4 by frees_sort/
173 | #f2 #I #L #W #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
174 lapply (isfin_inv_next … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
175 elim (lifts_inv_lref2 … H2) -H2 #i #H2 #H destruct
176 lapply (at_inv_xxp … H2 ?) -H2 // * #g #H #H0 destruct
177 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #HVW #H destruct
178 elim (coafter_inv_pxn … H3) -H3 [ |*: // ] #g1 #Hf2 #H destruct
179 /3 width=4 by frees_zero/
180 | #f2 #I #L #W #j #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
181 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
182 elim (lifts_inv_lref2 … H2) -H2 #x #H2 #H destruct
183 elim (coafter_inv_xxp … H3) -H3 [1,3: * |*: // ]
184 [ #g #g1 #Hf2 #H #H0 destruct
185 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #HVW #H destruct
186 elim (at_inv_xpn … H2) -H2 [ |*: // ] #j #Hg #H destruct
187 | #g #Hf2 #H destruct
188 lapply (drops_inv_drop1 … H1) -H1
189 lapply (at_inv_xnn … H2 ????) -H2 [5: |*: // ]
190 ] /4 width=4 by lifts_lref, frees_lref/
191 | #f2 #I #L #W #l #_ #IH #Hf2 #f #Y #H1 #T #H2 #f1 #H3
192 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
193 lapply (lifts_inv_gref2 … H2) -H2 #H destruct
194 elim (coafter_inv_xxp … H3) -H3 [1,3: * |*: // ]
195 [ #g #g1 #Hf2 #H #H0 destruct
196 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
197 | #g #Hf2 #H destruct
198 lapply (drops_inv_drop1 … H1) -H1
199 ] /3 width=4 by frees_gref/
200 | #f2W #f2U #f2 #p #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #X #H2 #f1 #H3
201 elim (sor_inv_isfin3 … H1f2) // #H1f2W #H
202 lapply (isfin_inv_tl … H) -H
203 elim (lifts_inv_bind2 … H2) -H2 #V #T #HVW #HTU #H destruct
204 elim (coafter_inv_sor … H3 … H1f2) -H3 -H1f2 // #f1W #f1U #H2f2W #H
205 elim (coafter_inv_tl0 … H) -H /4 width=5 by frees_bind, drops_skip/
206 | #f2W #f2U #f2 #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #X #H2 #f1 #H3
207 elim (sor_inv_isfin3 … H1f2) //
208 elim (lifts_inv_flat2 … H2) -H2 #V #T #HVW #HTU #H destruct
209 elim (coafter_inv_sor … H3 … H1f2) -H3 -H1f2 /3 width=5 by frees_flat/
213 lemma frees_inv_drops: ∀f2,L,U. L ⊢ 𝐅*⦃U⦄ ≡ f2 →
214 ∀f,K. ⬇*[Ⓣ, f] L ≡ K → ∀f1. f ~⊚ f1 ≡ f2 →
215 ∃∃T. K ⊢ 𝐅*⦃T⦄ ≡ f1 & ⬆*[f] T ≡ U.
216 #f2 #L #U #H lapply (frees_fwd_isfin … H) elim H -f2 -L -U
217 [ #f2 #I #Hf2 #_ #f #K #H1 #f1 #H2
218 lapply (coafter_fwd_isid2 … H2 ??) -H2 // -Hf2 #Hf1
219 elim (drops_inv_atom1 … H1) -H1 #H #Hf destruct
220 /4 width=3 by frees_atom, lifts_refl, ex2_intro/
221 | #f2 #I #L #W #s #_ #IH #Hf2 #f #Y #H1 #f1 #H2
222 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
223 elim (coafter_inv_xxp … H2) -H2 [1,3: * |*: // ]
224 [ #g #g1 #Hf2 #H #H0 destruct
225 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
226 | #g #Hf2 #H destruct
227 lapply (drops_inv_drop1 … H1) -H1 #HLK
229 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
230 lapply (lifts_inv_sort2 … HX) -HX #H destruct
231 /3 width=3 by frees_sort, lifts_sort, ex2_intro/
232 | #f2 #I #L #W #_ #IH #Hf2 #f #Y #H1 #f1 #H2
233 lapply (isfin_inv_next … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
234 elim (coafter_inv_xxn … H2) -H2 [ |*: // ] #g #g1 #Hf2 #H0 #H destruct
235 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #HVW #H destruct
236 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
237 lapply (lifts_inj … HX … HVW) -W #H destruct
238 /3 width=3 by frees_zero, lifts_lref, ex2_intro/
239 | #f2 #I #L #W #j #_ #IH #Hf2 #f #Y #H1 #f1 #H2
240 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
241 elim (coafter_inv_xxp … H2) -H2 [1,3: * |*: // ]
242 [ #g #g1 #Hf2 #H #H0 destruct
243 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
244 | #g #Hf2 #H destruct
245 lapply (drops_inv_drop1 … H1) -H1 #HLK
247 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
248 elim (lifts_inv_lref2 … HX) -HX #i #Hij #H destruct
249 /4 width=7 by frees_lref, lifts_lref, at_S1, at_next, ex2_intro/
250 | #f2 #I #L #W #l #_ #IH #Hf2 #f #Y #H1 #f1 #H2
251 lapply (isfin_fwd_push … Hf2 ??) -Hf2 [3: |*: // ] #Hf2
252 elim (coafter_inv_xxp … H2) -H2 [1,3: * |*: // ]
253 [ #g #g1 #Hf2 #H #H0 destruct
254 elim (drops_inv_skip1 … H1) -H1 #K #V #HLK #_ #H destruct
255 | #g #Hf2 #H destruct
256 lapply (drops_inv_drop1 … H1) -H1 #HLK
258 elim (IH … HLK … Hf2) -L // -f2 #X #Hg1 #HX
259 lapply (lifts_inv_gref2 … HX) -HX #H destruct
260 /3 width=3 by frees_gref, lifts_gref, ex2_intro/
261 | #f2W #f2U #f2 #p #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #f1 #H2
262 elim (sor_inv_isfin3 … H1f2) // #H1f2W #H
263 lapply (isfin_inv_tl … H) -H #H1f2U
264 elim (coafter_inv_sor … H2 … H1f2) -H2 -H1f2 // #f1W #f1U #H2f2W #H #Hf1
265 elim (coafter_inv_tl0 … H) -H #g1 #H2f2U #H destruct
266 elim (IHW … H1 … H2f2W) -IHW -H2f2W // -H1f2W #V #Hf1W #HVW
267 elim (IHU … H2f2U) -IHU -H2f2U
268 /3 width=5 by frees_bind, drops_skip, lifts_bind, ex2_intro/
269 | #f2W #f2U #f2 #I #L #W #U #_ #_ #H1f2 #IHW #IHU #H2f2 #f #K #H1 #f1 #H2
270 elim (sor_inv_isfin3 … H1f2) // #H1f2W #H1f2U
271 elim (coafter_inv_sor … H2 … H1f2) -H2 -H1f2 // #f1W #f1U #H2f2W #H2f2U #Hf1
272 elim (IHW … H1 … H2f2W) -IHW -H2f2W // -H1f2W
273 elim (IHU … H1 … H2f2U) -L -H2f2U
274 /3 width=5 by frees_flat, lifts_flat, ex2_intro/