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_id.ma".
16 include "basic_2/notation/relations/relationstar_4.ma".
17 include "basic_2/syntax/cext2.ma".
18 include "basic_2/relocation/lexs.ma".
19 include "basic_2/static/frees.ma".
21 (* GENERIC EXTENSION ON REFERRED ENTRIES OF A CONTEXT-SENSITIVE REALTION ****)
23 definition lfxs (R) (T): relation lenv ≝
24 λL1,L2. ∃∃f. L1 ⊢ 𝐅*⦃T⦄ ≘ f & L1 ⪤*[cext2 R, cfull, f] L2.
26 interpretation "generic extension on referred entries (local environment)"
27 'RelationStar R T L1 L2 = (lfxs R T L1 L2).
29 definition R_confluent2_lfxs: relation4 (relation3 lenv term term)
30 (relation3 lenv term term) … ≝
32 ∀L0,T0,T1. R1 L0 T0 T1 → ∀T2. R2 L0 T0 T2 →
33 ∀L1. L0 ⪤*[RP1, T0] L1 → ∀L2. L0 ⪤*[RP2, T0] L2 →
34 ∃∃T. R2 L1 T1 T & R1 L2 T2 T.
36 definition lfxs_confluent: relation … ≝
38 ∀K1,K,V1. K1 ⪤*[R1, V1] K → ∀V. R1 K1 V1 V →
39 ∀K2. K ⪤*[R2, V] K2 → K ⪤*[R2, V1] K2.
41 definition lfxs_transitive: relation3 ? (relation3 ?? term) … ≝
43 ∀K1,K,V1. K1 ⪤*[R1, V1] K →
44 ∀V. R1 K1 V1 V → ∀V2. R2 K V V2 → R3 K1 V1 V2.
46 (* Basic inversion lemmas ***************************************************)
48 lemma lfxs_inv_atom_sn (R): ∀Y2,T. ⋆ ⪤*[R, T] Y2 → Y2 = ⋆.
49 #R #Y2 #T * /2 width=4 by lexs_inv_atom1/
52 lemma lfxs_inv_atom_dx (R): ∀Y1,T. Y1 ⪤*[R, T] ⋆ → Y1 = ⋆.
53 #R #I #Y1 * /2 width=4 by lexs_inv_atom2/
56 lemma lfxs_inv_sort (R): ∀Y1,Y2,s. Y1 ⪤*[R, ⋆s] Y2 →
58 | ∃∃I1,I2,L1,L2. L1 ⪤*[R, ⋆s] L2 &
59 Y1 = L1.ⓘ{I1} & Y2 = L2.ⓘ{I2}.
60 #R * [ | #Y1 #I1 ] #Y2 #s * #f #H1 #H2
61 [ lapply (lexs_inv_atom1 … H2) -H2 /3 width=1 by or_introl, conj/
62 | lapply (frees_inv_sort … H1) -H1 #Hf
63 elim (isid_inv_gen … Hf) -Hf #g #Hg #H destruct
64 elim (lexs_inv_push1 … H2) -H2 #I2 #L2 #H12 #_ #H destruct
65 /5 width=7 by frees_sort, ex3_4_intro, ex2_intro, or_intror/
69 lemma lfxs_inv_zero (R): ∀Y1,Y2. Y1 ⪤*[R, #0] Y2 →
71 | ∃∃I,L1,L2,V1,V2. L1 ⪤*[R, V1] L2 & R L1 V1 V2 &
72 Y1 = L1.ⓑ{I}V1 & Y2 = L2.ⓑ{I}V2
73 | ∃∃f,I,L1,L2. 𝐈⦃f⦄ & L1 ⪤*[cext2 R, cfull, f] L2 &
74 Y1 = L1.ⓤ{I} & Y2 = L2.ⓤ{I}.
75 #R * [ | #Y1 * #I1 [ | #X ] ] #Y2 * #f #H1 #H2
76 [ lapply (lexs_inv_atom1 … H2) -H2 /3 width=1 by or3_intro0, conj/
77 | elim (frees_inv_unit … H1) -H1 #g #HX #H destruct
78 elim (lexs_inv_next1 … H2) -H2 #I2 #L2 #HL12 #H #H2 destruct
79 >(ext2_inv_unit_sn … H) -H /3 width=8 by or3_intro2, ex4_4_intro/
80 | elim (frees_inv_pair … H1) -H1 #g #Hg #H destruct
81 elim (lexs_inv_next1 … H2) -H2 #Z2 #L2 #HL12 #H
82 elim (ext2_inv_pair_sn … H) -H
83 /4 width=9 by or3_intro1, ex4_5_intro, ex2_intro/
87 lemma lfxs_inv_lref (R): ∀Y1,Y2,i. Y1 ⪤*[R, #↑i] Y2 →
89 | ∃∃I1,I2,L1,L2. L1 ⪤*[R, #i] L2 &
90 Y1 = L1.ⓘ{I1} & Y2 = L2.ⓘ{I2}.
91 #R * [ | #Y1 #I1 ] #Y2 #i * #f #H1 #H2
92 [ lapply (lexs_inv_atom1 … H2) -H2 /3 width=1 by or_introl, conj/
93 | elim (frees_inv_lref … H1) -H1 #g #Hg #H destruct
94 elim (lexs_inv_push1 … H2) -H2
95 /4 width=7 by ex3_4_intro, ex2_intro, or_intror/
99 lemma lfxs_inv_gref (R): ∀Y1,Y2,l. Y1 ⪤*[R, §l] Y2 →
101 | ∃∃I1,I2,L1,L2. L1 ⪤*[R, §l] L2 &
102 Y1 = L1.ⓘ{I1} & Y2 = L2.ⓘ{I2}.
103 #R * [ | #Y1 #I1 ] #Y2 #l * #f #H1 #H2
104 [ lapply (lexs_inv_atom1 … H2) -H2 /3 width=1 by or_introl, conj/
105 | lapply (frees_inv_gref … H1) -H1 #Hf
106 elim (isid_inv_gen … Hf) -Hf #g #Hg #H destruct
107 elim (lexs_inv_push1 … H2) -H2 #I2 #L2 #H12 #_ #H destruct
108 /5 width=7 by frees_gref, ex3_4_intro, ex2_intro, or_intror/
112 (* Basic_2A1: uses: llpx_sn_inv_bind llpx_sn_inv_bind_O *)
113 lemma lfxs_inv_bind (R): ∀p,I,L1,L2,V1,V2,T. L1 ⪤*[R, ⓑ{p,I}V1.T] L2 → R L1 V1 V2 →
114 ∧∧ L1 ⪤*[R, V1] L2 & L1.ⓑ{I}V1 ⪤*[R, T] L2.ⓑ{I}V2.
115 #R #p #I #L1 #L2 #V1 #V2 #T * #f #Hf #HL #HV elim (frees_inv_bind … Hf) -Hf
116 /6 width=6 by sle_lexs_trans, lexs_inv_tl, ext2_pair, sor_inv_sle_dx, sor_inv_sle_sn, ex2_intro, conj/
119 (* Basic_2A1: uses: llpx_sn_inv_flat *)
120 lemma lfxs_inv_flat (R): ∀I,L1,L2,V,T. L1 ⪤*[R, ⓕ{I}V.T] L2 →
121 ∧∧ L1 ⪤*[R, V] L2 & L1 ⪤*[R, T] L2.
122 #R #I #L1 #L2 #V #T * #f #Hf #HL elim (frees_inv_flat … Hf) -Hf
123 /5 width=6 by sle_lexs_trans, sor_inv_sle_dx, sor_inv_sle_sn, ex2_intro, conj/
126 (* Advanced inversion lemmas ************************************************)
128 lemma lfxs_inv_sort_bind_sn (R): ∀I1,K1,L2,s. K1.ⓘ{I1} ⪤*[R, ⋆s] L2 →
129 ∃∃I2,K2. K1 ⪤*[R, ⋆s] K2 & L2 = K2.ⓘ{I2}.
130 #R #I1 #K1 #L2 #s #H elim (lfxs_inv_sort … H) -H *
132 | #Z1 #I2 #Y1 #K2 #Hs #H1 #H2 destruct /2 width=4 by ex2_2_intro/
136 lemma lfxs_inv_sort_bind_dx (R): ∀I2,K2,L1,s. L1 ⪤*[R, ⋆s] K2.ⓘ{I2} →
137 ∃∃I1,K1. K1 ⪤*[R, ⋆s] K2 & L1 = K1.ⓘ{I1}.
138 #R #I2 #K2 #L1 #s #H elim (lfxs_inv_sort … H) -H *
140 | #I1 #Z2 #K1 #Y2 #Hs #H1 #H2 destruct /2 width=4 by ex2_2_intro/
144 lemma lfxs_inv_zero_pair_sn (R): ∀I,L2,K1,V1. K1.ⓑ{I}V1 ⪤*[R, #0] L2 →
145 ∃∃K2,V2. K1 ⪤*[R, V1] K2 & R K1 V1 V2 &
147 #R #I #L2 #K1 #V1 #H elim (lfxs_inv_zero … H) -H *
149 | #Z #Y1 #K2 #X1 #V2 #HK12 #HV12 #H1 #H2 destruct
150 /2 width=5 by ex3_2_intro/
151 | #f #Z #Y1 #Y2 #_ #_ #H destruct
155 lemma lfxs_inv_zero_pair_dx (R): ∀I,L1,K2,V2. L1 ⪤*[R, #0] K2.ⓑ{I}V2 →
156 ∃∃K1,V1. K1 ⪤*[R, V1] K2 & R K1 V1 V2 &
158 #R #I #L1 #K2 #V2 #H elim (lfxs_inv_zero … H) -H *
160 | #Z #K1 #Y2 #V1 #X2 #HK12 #HV12 #H1 #H2 destruct
161 /2 width=5 by ex3_2_intro/
162 | #f #Z #Y1 #Y2 #_ #_ #_ #H destruct
166 lemma lfxs_inv_zero_unit_sn (R): ∀I,K1,L2. K1.ⓤ{I} ⪤*[R, #0] L2 →
167 ∃∃f,K2. 𝐈⦃f⦄ & K1 ⪤*[cext2 R, cfull, f] K2 &
169 #R #I #K1 #L2 #H elim (lfxs_inv_zero … H) -H *
171 | #Z #Y1 #Y2 #X1 #X2 #_ #_ #H destruct
172 | #f #Z #Y1 #K2 #Hf #HK12 #H1 #H2 destruct /2 width=5 by ex3_2_intro/
176 lemma lfxs_inv_zero_unit_dx (R): ∀I,L1,K2. L1 ⪤*[R, #0] K2.ⓤ{I} →
177 ∃∃f,K1. 𝐈⦃f⦄ & K1 ⪤*[cext2 R, cfull, f] K2 &
179 #R #I #L1 #K2 #H elim (lfxs_inv_zero … H) -H *
181 | #Z #Y1 #Y2 #X1 #X2 #_ #_ #_ #H destruct
182 | #f #Z #K1 #Y2 #Hf #HK12 #H1 #H2 destruct /2 width=5 by ex3_2_intro/
186 lemma lfxs_inv_lref_bind_sn (R): ∀I1,K1,L2,i. K1.ⓘ{I1} ⪤*[R, #↑i] L2 →
187 ∃∃I2,K2. K1 ⪤*[R, #i] K2 & L2 = K2.ⓘ{I2}.
188 #R #I1 #K1 #L2 #i #H elim (lfxs_inv_lref … H) -H *
190 | #Z1 #I2 #Y1 #K2 #Hi #H1 #H2 destruct /2 width=4 by ex2_2_intro/
194 lemma lfxs_inv_lref_bind_dx (R): ∀I2,K2,L1,i. L1 ⪤*[R, #↑i] K2.ⓘ{I2} →
195 ∃∃I1,K1. K1 ⪤*[R, #i] K2 & L1 = K1.ⓘ{I1}.
196 #R #I2 #K2 #L1 #i #H elim (lfxs_inv_lref … H) -H *
198 | #I1 #Z2 #K1 #Y2 #Hi #H1 #H2 destruct /2 width=4 by ex2_2_intro/
202 lemma lfxs_inv_gref_bind_sn (R): ∀I1,K1,L2,l. K1.ⓘ{I1} ⪤*[R, §l] L2 →
203 ∃∃I2,K2. K1 ⪤*[R, §l] K2 & L2 = K2.ⓘ{I2}.
204 #R #I1 #K1 #L2 #l #H elim (lfxs_inv_gref … H) -H *
206 | #Z1 #I2 #Y1 #K2 #Hl #H1 #H2 destruct /2 width=4 by ex2_2_intro/
210 lemma lfxs_inv_gref_bind_dx (R): ∀I2,K2,L1,l. L1 ⪤*[R, §l] K2.ⓘ{I2} →
211 ∃∃I1,K1. K1 ⪤*[R, §l] K2 & L1 = K1.ⓘ{I1}.
212 #R #I2 #K2 #L1 #l #H elim (lfxs_inv_gref … H) -H *
214 | #I1 #Z2 #K1 #Y2 #Hl #H1 #H2 destruct /2 width=4 by ex2_2_intro/
218 (* Basic forward lemmas *****************************************************)
220 lemma lfxs_fwd_zero_pair (R): ∀I,K1,K2,V1,V2.
221 K1.ⓑ{I}V1 ⪤*[R, #0] K2.ⓑ{I}V2 → K1 ⪤*[R, V1] K2.
222 #R #I #K1 #K2 #V1 #V2 #H
223 elim (lfxs_inv_zero_pair_sn … H) -H #Y #X #HK12 #_ #H destruct //
226 (* Basic_2A1: uses: llpx_sn_fwd_pair_sn llpx_sn_fwd_bind_sn llpx_sn_fwd_flat_sn *)
227 lemma lfxs_fwd_pair_sn (R): ∀I,L1,L2,V,T. L1 ⪤*[R, ②{I}V.T] L2 → L1 ⪤*[R, V] L2.
228 #R * [ #p ] #I #L1 #L2 #V #T * #f #Hf #HL
229 [ elim (frees_inv_bind … Hf) | elim (frees_inv_flat … Hf) ] -Hf
230 /4 width=6 by sle_lexs_trans, sor_inv_sle_sn, ex2_intro/
233 (* Basic_2A1: uses: llpx_sn_fwd_bind_dx llpx_sn_fwd_bind_O_dx *)
234 lemma lfxs_fwd_bind_dx (R): ∀p,I,L1,L2,V1,V2,T. L1 ⪤*[R, ⓑ{p,I}V1.T] L2 →
235 R L1 V1 V2 → L1.ⓑ{I}V1 ⪤*[R, T] L2.ⓑ{I}V2.
236 #R #p #I #L1 #L2 #V1 #V2 #T #H #HV elim (lfxs_inv_bind … H HV) -H -HV //
239 (* Basic_2A1: uses: llpx_sn_fwd_flat_dx *)
240 lemma lfxs_fwd_flat_dx (R): ∀I,L1,L2,V,T. L1 ⪤*[R, ⓕ{I}V.T] L2 → L1 ⪤*[R, T] L2.
241 #R #I #L1 #L2 #V #T #H elim (lfxs_inv_flat … H) -H //
244 lemma lfxs_fwd_dx (R): ∀I2,L1,K2,T. L1 ⪤*[R, T] K2.ⓘ{I2} →
245 ∃∃I1,K1. L1 = K1.ⓘ{I1}.
246 #R #I2 #L1 #K2 #T * #f elim (pn_split f) * #g #Hg #_ #Hf destruct
247 [ elim (lexs_inv_push2 … Hf) | elim (lexs_inv_next2 … Hf) ] -Hf #I1 #K1 #_ #_ #H destruct
248 /2 width=3 by ex1_2_intro/
251 (* Basic properties *********************************************************)
253 lemma lfxs_atom (R): ∀I. ⋆ ⪤*[R, ⓪{I}] ⋆.
254 #R * /3 width=3 by frees_sort, frees_atom, frees_gref, lexs_atom, ex2_intro/
257 lemma lfxs_sort (R): ∀I1,I2,L1,L2,s.
258 L1 ⪤*[R, ⋆s] L2 → L1.ⓘ{I1} ⪤*[R, ⋆s] L2.ⓘ{I2}.
259 #R #I1 #I2 #L1 #L2 #s * #f #Hf #H12
260 lapply (frees_inv_sort … Hf) -Hf
261 /4 width=3 by frees_sort, lexs_push, isid_push, ex2_intro/
264 lemma lfxs_pair (R): ∀I,L1,L2,V1,V2. L1 ⪤*[R, V1] L2 →
265 R L1 V1 V2 → L1.ⓑ{I}V1 ⪤*[R, #0] L2.ⓑ{I}V2.
266 #R #I1 #I2 #L1 #L2 #V1 *
267 /4 width=3 by ext2_pair, frees_pair, lexs_next, ex2_intro/
270 lemma lfxs_unit (R): ∀f,I,L1,L2. 𝐈⦃f⦄ → L1 ⪤*[cext2 R, cfull, f] L2 →
271 L1.ⓤ{I} ⪤*[R, #0] L2.ⓤ{I}.
272 /4 width=3 by frees_unit, lexs_next, ext2_unit, ex2_intro/ qed.
274 lemma lfxs_lref (R): ∀I1,I2,L1,L2,i.
275 L1 ⪤*[R, #i] L2 → L1.ⓘ{I1} ⪤*[R, #↑i] L2.ⓘ{I2}.
276 #R #I1 #I2 #L1 #L2 #i * /3 width=3 by lexs_push, frees_lref, ex2_intro/
279 lemma lfxs_gref (R): ∀I1,I2,L1,L2,l.
280 L1 ⪤*[R, §l] L2 → L1.ⓘ{I1} ⪤*[R, §l] L2.ⓘ{I2}.
281 #R #I1 #I2 #L1 #L2 #l * #f #Hf #H12
282 lapply (frees_inv_gref … Hf) -Hf
283 /4 width=3 by frees_gref, lexs_push, isid_push, ex2_intro/
286 lemma lfxs_bind_repl_dx (R): ∀I,I1,L1,L2,T.
287 L1.ⓘ{I} ⪤*[R, T] L2.ⓘ{I1} →
288 ∀I2. cext2 R L1 I I2 →
289 L1.ⓘ{I} ⪤*[R, T] L2.ⓘ{I2}.
290 #R #I #I1 #L1 #L2 #T * #f #Hf #HL12 #I2 #HR
291 /3 width=5 by lexs_pair_repl, ex2_intro/
294 (* Basic_2A1: uses: llpx_sn_co *)
295 lemma lfxs_co (R1) (R2): (∀L,T1,T2. R1 L T1 T2 → R2 L T1 T2) →
296 ∀L1,L2,T. L1 ⪤*[R1, T] L2 → L1 ⪤*[R2, T] L2.
297 #R1 #R2 #HR #L1 #L2 #T * /5 width=7 by lexs_co, cext2_co, ex2_intro/
300 lemma lfxs_isid (R1) (R2): ∀L1,L2,T1,T2.
301 (∀f. L1 ⊢ 𝐅*⦃T1⦄ ≘ f → 𝐈⦃f⦄) →
302 (∀f. 𝐈⦃f⦄ → L1 ⊢ 𝐅*⦃T2⦄ ≘ f) →
303 L1 ⪤*[R1, T1] L2 → L1 ⪤*[R2, T2] L2.
304 #R1 #R2 #L1 #L2 #T1 #T2 #H1 #H2 *
305 /4 width=7 by lexs_co_isid, ex2_intro/
308 lemma lfxs_unit_sn (R1) (R2):
309 ∀I,K1,L2. K1.ⓤ{I} ⪤*[R1, #0] L2 → K1.ⓤ{I} ⪤*[R2, #0] L2.
310 #R1 #R2 #I #K1 #L2 #H
311 elim (lfxs_inv_zero_unit_sn … H) -H #f #K2 #Hf #HK12 #H destruct
312 /3 width=7 by lfxs_unit, lexs_co_isid/
315 (* Basic_2A1: removed theorems 9:
316 llpx_sn_skip llpx_sn_lref llpx_sn_free
318 llpx_sn_Y llpx_sn_ge_up llpx_sn_ge
319 llpx_sn_fwd_drop_sn llpx_sn_fwd_drop_dx