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 "nat_ordered_set.ma".
16 include "models/q_bars.ma".
18 axiom le_le_eq: ∀x,y:Q. x ≤ y → y ≤ x → x = y.
20 lemma initial_shift_same_values:
21 ∀l1:q_f.∀init.init < start l1 →
23 (mk_q_f init (〈\fst (unpos (start l1 - init) ?),OQ〉:: bars l1)).
24 [apply hide; apply q_lt_minus; rewrite > q_plus_sym; rewrite > q_plus_OQ; assumption]
25 intros; generalize in ⊢ (? ? (? ? (? ? (? ? ? (? ? ? (? ? %)) ?) ?))); intro;
26 cases (unpos (start l1-init) H1); intro input;
27 simplify in ⊢ (? ? ? (? ? ? (? ? ? (? (? ? (? ? (? ? ? % ?) ?)) ?))));
28 cases (value (mk_q_f init (〈w,OQ〉::bars l1)) input);
29 simplify in ⊢ (? ? ? (? ? ? %));
30 cases (q_cmp input (start (mk_q_f init (〈w,OQ〉::bars l1)))) in H3;
31 whd in ⊢ (% → ?); simplify in H3;
32 [1: intro; cases H4; clear H4; rewrite > H3;
33 cases (value l1 init); simplify; cases (q_cmp init (start l1)) in H4;
34 [1: cases (?:False); apply (q_lt_corefl init); rewrite > H4 in ⊢ (?? %); apply H;
35 |3: cases (?:False); apply (q_lt_antisym init (start l1)); assumption;
36 |2: whd in ⊢ (% → ?); intro; rewrite > H8; clear H8 H4;
37 rewrite > H7; clear H7; rewrite > (?:\fst w1 = O); [reflexivity]
38 symmetry; apply le_n_O_to_eq;
39 rewrite > (sum_bases_O (mk_q_f init (〈w,OQ〉::bars l1)) (\fst w1)); [apply le_n]
40 clear H6 w2; simplify in H5:(? ? (? ? %));
41 destruct H3; rewrite > q_d_x_x in H5; assumption;]
42 |2: intros; cases (value l1 input); simplify in ⊢ (? ? (? ? ? %) ?);
43 cases (q_cmp input (start l1)) in H5; whd in ⊢ (% → ?);
44 [1: cases (?:False); clear w2 H4 w1 H2 w H1;
45 apply (q_lt_antisym init (start l1)); [assumption] rewrite < H5; assumption
46 |2: intros; rewrite > H6; clear H6; rewrite > H4; reflexivity;
47 |3: cases (?:False); apply (q_lt_antisym input (start l1)); [2: assumption]
48 apply (q_lt_trans ??? H3 H);]
49 |3: intro; cases H4; clear H4;
50 cases (value l1 input); simplify; cases (q_cmp input (start l1)) in H4; whd in ⊢ (% → ?);
51 [1: intro; cases H8; clear H8; rewrite > H11; rewrite > H7; clear H11 H7;
52 simplify in ⊢ (? ? ? (? ? ? (? ? % ? ?)));
53 cut (\fst w1 = S (\fst w2)) as Key; [rewrite > Key; reflexivity;]
54 cut (\fst w2 = O); [2: clear H10;
55 symmetry; apply le_n_O_to_eq; rewrite > (sum_bases_O l1 (\fst w2)); [apply le_n]
56 apply (q_le_trans ??? H9); rewrite < H4; rewrite > q_d_x_x;
57 apply q_eq_to_le; reflexivity;]
58 rewrite > Hcut; clear Hcut H10 H9; simplify in H5 H6;
59 cut (ⅆ[input,init] = Qpos w) as E; [2:
60 rewrite > H2; rewrite < H4; rewrite > q_d_sym;
61 rewrite > q_d_noabs; [reflexivity] apply q_lt_to_le; assumption;]
62 cases (\fst w1) in H5 H6; intros;
63 [1: cases (?:False); clear H5; simplify in H6;
64 apply (q_lt_corefl ⅆ[input,init]);
65 rewrite > E in ⊢ (??%); rewrite < q_plus_OQ in ⊢ (??%);
66 rewrite > q_plus_sym; assumption;
67 |2: cases n in H5 H6; [intros; reflexivity] intros;
68 cases (?:False); clear H6; cases (bars l1) in H5; simplify; intros;
69 [apply (q_pos_OQ one);|apply (q_pos_OQ (\fst b));]
70 apply (q_le_S ??? (sum_bases_ge_OQ ? n1));[apply []|3:apply l]
71 simplify in ⊢ (? (? (? % ?) ?) ?); rewrite < (q_plus_minus (Qpos w));
72 rewrite > q_elim_minus; apply q_le_minus_r;
73 rewrite > q_elim_opp; rewrite < E in ⊢ (??%); assumption;]
74 |2: intros; rewrite > H8; rewrite > H7; clear H8 H7;
75 simplify in H5 H6 ⊢ %;
76 cases (\fst w1) in H5 H6; [intros; reflexivity]
78 [1: intros; simplify; elim n [reflexivity] simplify; assumption;
79 |2: simplify; intros; cases (?:False); clear H6;
80 apply (q_lt_le_incompat (input - init) (Qpos w) );
81 [1: rewrite > H2; do 2 rewrite > q_elim_minus;
82 apply q_lt_plus; rewrite > q_elim_minus;
83 rewrite < q_plus_assoc; rewrite < q_elim_minus;
84 rewrite > q_plus_minus;rewrite > q_plus_OQ; assumption;
85 |2: rewrite < q_d_noabs; [2: apply q_lt_to_le; assumption]
88 ; apply (q_le_S ???? H5);apply sum_bases_ge_OQ;]]
89 |3: intro; cases H8; clear H8; rewrite > H11; rewrite > H7; clear H11 H7;
90 simplify in H5 H6 ⊢ (? ? ? (? ? ? (? ? % ? ?)));
92 axiom nth_nil: ∀T,n.∀d:T. nth [] d n = d.
95 ∀init,input,l1,w1,w2,w.
96 Qpos w = start l1 - init →
99 sum_bases (〈w,OQ〉::bars l1) w1 ≤ ⅆ[input,init] →
100 ⅆ[input,init] < sum_bases (bars l1) w1 + (start l1-init) →
101 sum_bases (bars l1) w2 ≤ ⅆ[input,start l1] →
102 ⅆ[input,start l1] < sum_bases (bars l1) (S w2) →
103 \snd (nth (bars l1) ▭ w2) = \snd (nth (〈w,OQ〉::bars l1) ▭ w1).
104 intros 4 (init input l); cases l (st l);
105 change in match (start (mk_q_f st l)) with st;
106 change in match (bars (mk_q_f st l)) with l;
108 [1: rewrite > nth_nil; cases w1 in H4;
109 [1: rewrite > q_d_sym; rewrite > q_d_noabs; [2:
110 apply (q_le_trans ? st); apply q_lt_to_le; assumption]
111 do 2 rewrite > q_elim_minus; rewrite > q_plus_assoc;
112 intro X; lapply (q_lt_canc_plus_r ??? X) as Y;
113 simplify in Y; cases (?:False);
114 apply (q_lt_corefl st); apply (q_lt_trans ??? H2);
115 apply (q_lt_le_trans ??? Y); rewrite > q_plus_sym; rewrite > q_plus_OQ;
116 apply q_eq_to_le; reflexivity;
117 |2: intros; simplify; rewrite > nth_nil; reflexivity;]
120 (* interesting case: init < start < input *)
121 intro; cases H8; clear H8; rewrite > H11; rewrite > H7; clear H11 H7;
122 simplify in H5 H6 ⊢ (? ? ? (? ? ? (? ? % ? ?)));
123 elim (\fst w2) in H9 H10;
124 [1: elim (\fst w1) in H5 H6;
125 [1: cases (?:False); clear H5 H8 H7;
126 apply (q_lt_antisym input (start l1)); [2: assumption]
127 rewrite > q_d_sym in H6; rewrite > q_d_noabs in H6;
128 [2: apply q_lt_to_le; assumption]
129 rewrite > q_plus_sym in H6; rewrite > q_plus_OQ in H6;
130 rewrite > H2 in H6; apply (q_lt_canc_plus_r ?? (Qopp init));
131 do 2 rewrite < q_elim_minus; assumption;
134 cut (\fst w1 = S (\fst w2)) as Key; [rewrite > Key; reflexivity;]
135 cases (\fst w1) in H5 H6; intros; [1:
136 cases (?:False); clear H5 H9 H10;
137 apply (q_lt_antisym input (start l1)); [2: assumption]
138 rewrite > q_d_sym in H6; rewrite > q_d_noabs in H6;
139 [2: apply q_lt_to_le; assumption]
140 rewrite > q_plus_sym in H6; rewrite > q_plus_OQ in H6;
141 rewrite > H2 in H6; apply (q_lt_canc_plus_r ?? (Qopp init));
142 do 2 rewrite < q_elim_minus; assumption;]
144 cut (sum_bases (bars l1) (\fst w2) < sum_bases (bars l1) (S n));[2:
145 apply (q_le_lt_trans ??? H9);
146 apply (q_lt_trans ??? ? H6);
147 rewrite > q_d_sym; rewrite > q_d_noabs; [2:apply q_lt_to_le;assumption]
148 rewrite > q_d_sym; rewrite > q_d_noabs; [2:apply q_lt_to_le;assumption]
149 do 2 rewrite > q_elim_minus; rewrite > (q_plus_sym ? (Qopp init));
150 apply q_lt_plus; rewrite > q_plus_sym;
151 rewrite > q_elim_minus; rewrite < q_plus_assoc;
152 rewrite < q_elim_minus; rewrite > q_plus_minus;
153 rewrite > q_plus_OQ; apply q_lt_opp_opp; assumption]
155 cut (ⅆ[input,init] - Qpos w = ⅆ[input,start l1]);[2:
156 rewrite > q_d_sym; rewrite > q_d_noabs; [2:apply q_lt_to_le;assumption]
157 rewrite > q_d_sym; rewrite > q_d_noabs; [2:apply q_lt_to_le;assumption]
158 rewrite > H2; rewrite > (q_elim_minus (start ?));
159 rewrite > q_minus_distrib; rewrite > q_elim_opp;
160 do 2 rewrite > q_elim_minus;
161 do 2 rewrite < q_plus_assoc;
162 rewrite > (q_plus_sym ? init);
163 rewrite > (q_plus_assoc ? init);
164 rewrite > (q_plus_sym ? init);
165 rewrite < (q_elim_minus init); rewrite > q_plus_minus;
166 rewrite > (q_plus_sym OQ); rewrite > q_plus_OQ;
167 rewrite < q_elim_minus; reflexivity;]
168 cut (sum_bases (bars l1) n < sum_bases (bars l1) (S (\fst w2)));[2:
169 apply (q_le_lt_trans ???? H10); rewrite < Hcut1;
170 rewrite > q_elim_minus; apply q_le_minus_r; rewrite > q_elim_opp;
171 assumption;] clear Hcut1 H5 H10;
172 generalize in match Hcut;generalize in match Hcut2;clear Hcut Hcut2;
173 apply (nat_elim2 ???? n (\fst w2));
174 [3: intros (x y); apply eq_f; apply H5; clear H5;
175 [1: clear H7; apply sum_bases_lt_canc; assumption;
177 |2: intros; cases (?:False); clear H6;
178 cases n1 in H5; intro;
179 [1: apply (q_lt_corefl ? H5);
180 |2: cases (bars l1) in H5; intro;
182 apply (q_lt_le_incompat ?? (q_lt_canc_plus_r ??? H5));
183 apply q_le_plus_trans; [apply sum_bases_ge_OQ]
185 |2: simplify in H5:(??%);
186 lapply (q_lt_canc_plus_r (sum_bases l (S n2)) ?? H5) as X;
187 apply (q_lt_le_incompat ?? X); apply sum_bases_ge_OQ]]
188 |1: intro; cases n1 [intros; reflexivity] intros; cases (?:False);
193 [1: intro; elim n1; [reflexivity] cases (?:False);
197 elim n1 in H6; [reflexivity] cases (?:False);
198 [1: apply (q_lt_corefl ? H5);
199 |2: cases (bars l1) in H5; intro;
201 apply (q_lt_le_incompat ?? (q_lt_canc_plus_r ??? H5));
202 apply q_le_plus_trans; [apply sum_bases_ge_OQ]
204 |2: simplify in H5:(??%);
205 lapply (q_lt_canc_plus_r (sum_bases l (S n2)) ?? H5) as X;
206 apply (q_lt_le_incompat ?? X); apply sum_bases_ge_OQ]]
211 alias symbol "pi2" = "pair pi2".
212 alias symbol "pi1" = "pair pi1".
213 definition rebase_spec ≝
214 ∀l1,l2:q_f.∃p:q_f × q_f.
216 (*len (bars (\fst p)) = len (bars (\snd p))*)
217 (start (\fst p) = start (\snd p))
218 (same_bases (\fst p) (\snd p))
219 (same_values l1 (\fst p))
220 (same_values l2 (\snd p)).
222 definition rebase_spec_simpl ≝
223 λstart.λl1,l2:list bar.λp:(list bar) × (list bar).
225 (same_bases (mk_q_f start (\fst p)) (mk_q_f start (\snd p)))
226 (same_values (mk_q_f start l1) (mk_q_f start (\fst p)))
227 (same_values (mk_q_f start l2) (mk_q_f start (\snd p))).
229 (* a local letin makes russell fail *)
230 definition cb0h : list bar → list bar ≝
231 λl.mk_list (λi.〈\fst (nth l ▭ i),OQ〉) (len l).
234 λP.λp:∃x:(list bar) × (list bar).P x.match p with [ex_introT p _ ⇒ p].
236 definition inject ≝ λP.λp:(list bar) × (list bar).λh:P p. ex_introT ? P p h.
237 coercion inject with 0 1 nocomposites.
239 definition rebase: rebase_spec.
240 intros 2 (f1 f2); cases f1 (s1 l1); cases f2 (s2 l2); clear f1 f2;
242 λs.λl1,l2.λm.λz.len l1 + len l2 < m → rebase_spec_simpl s l1 l2 z);
243 alias symbol "pi1" (instance 34) = "exT \fst".
244 alias symbol "pi1" (instance 21) = "exT \fst".
246 let rec aux (l1,l2:list bar) (n:nat) on n : (list bar) × (list bar) ≝
248 [ O ⇒ 〈 nil ? , nil ? 〉
251 [ nil ⇒ 〈cb0h l2, l2〉
254 [ nil ⇒ 〈l1, cb0h l1〉
256 let base1 ≝ Qpos (\fst he1) in
257 let base2 ≝ Qpos (\fst he2) in
258 let height1 ≝ (\snd he1) in
259 let height2 ≝ (\snd he2) in
260 match q_cmp base1 base2 with
262 let rc ≝ aux tl1 tl2 m in
263 〈he1 :: \fst rc,he2 :: \snd rc〉
265 let rest ≝ base2 - base1 in
266 let rc ≝ aux tl1 (〈\fst (unpos rest ?),height2〉 :: tl2) m in
267 〈〈\fst he1,height1〉 :: \fst rc,〈\fst he1,height2〉 :: \snd rc〉
269 let rest ≝ base1 - base2 in
270 let rc ≝ aux (〈\fst (unpos rest ?),height1〉 :: tl1) tl2 m in
271 〈〈\fst he2,height1〉 :: \fst rc,〈\fst he2,height2〉 :: \snd rc〉
273 in aux : ∀l1,l2,m.∃z.∀s.spec s l1 l2 m z); unfold spec;
274 [9: clearbody aux; unfold spec in aux; clear spec;
276 [1: cases (aux l1 l2 (S (len l1 + len l2)));
277 cases (H1 s1 (le_n ?)); clear H1;
278 exists [apply 〈mk_q_f s1 (\fst w), mk_q_f s2 (\snd w)〉] split;
280 |3: intro; apply (H3 input);
281 |4: intro; rewrite > H in H4;
282 rewrite > (H4 input); reflexivity;]
283 |2: letin l2' ≝ (〈\fst (unpos (s2-s1) ?),OQ〉::l2);[
284 apply q_lt_minus; rewrite > q_plus_sym; rewrite > q_plus_OQ;
286 cases (aux l1 l2' (S (len l1 + len l2')));
287 cases (H1 s1 (le_n ?)); clear H1 aux;
288 exists [apply 〈mk_q_f s1 (\fst w), mk_q_f s1 (\snd w)〉] split;
292 |4: intro; rewrite < (H4 input); clear H3 H4 H2 w;
293 cases (value (mk_q_f s1 l2') input);
294 cases (q_cmp input (start (mk_q_f s1 l2'))) in H1;
296 [1: intros; cases H2; clear H2; whd in ⊢ (??? %);
297 cases (value (mk_q_f s2 l2) input);
298 cases (q_cmp input (start (mk_q_f s2 l2))) in H2;
300 [1: intros; cases H6; clear H6; change with (w1 = w);
303 |1,2: unfold rest; apply q_lt_minus; rewrite > q_plus_sym; rewrite > q_plus_OQ;
310 |8: intros; cases (?:False); apply (not_le_Sn_O ? H1);]