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 lemma sum_bars_increasing:
19 ∀l,x.sum_bases l x < sum_bases l (S x).
22 [1: simplify; rewrite > q_plus_sym; rewrite > q_plus_OQ;
24 |2: simplify in H ⊢ %;
25 apply q_lt_plus; rewrite > q_elim_minus;
26 rewrite < q_plus_assoc; rewrite < q_elim_minus;
27 rewrite > q_plus_minus; rewrite > q_plus_OQ;
30 [1: simplify; rewrite > q_plus_sym; rewrite > q_plus_OQ;
32 |2: simplify; change in ⊢ (? ? (? % ?)) with (sum_bases l1 (S n)) ;
33 apply q_lt_plus; rewrite > q_elim_minus;
34 rewrite < q_plus_assoc; rewrite < q_elim_minus;
35 rewrite > q_plus_minus; rewrite > q_plus_OQ; apply H]]
38 lemma q_lt_canc_plus_r:
39 ∀x,y,z:Q.x + z < y + z → x < y.
40 intros; rewrite < (q_plus_OQ y); rewrite < (q_plus_minus z);
41 rewrite > q_elim_minus; rewrite > q_plus_assoc;
42 apply q_lt_plus; rewrite > q_elim_opp; assumption;
45 lemma q_lt_inj_plus_r:
46 ∀x,y,z:Q.x < y → x + z < y + z.
47 intros; apply (q_lt_canc_plus_r ?? (Qopp z));
48 do 2 (rewrite < q_plus_assoc;rewrite < q_elim_minus);
49 rewrite > q_plus_minus;
50 do 2 rewrite > q_plus_OQ; assumption;
53 lemma sum_bases_lt_canc:
54 ∀l,x,y.sum_bases l (S x) < sum_bases l (S y) → sum_bases l x < sum_bases l y.
55 intro; elim l; [apply (q_lt_canc_plus_r ?? (Qpos one));apply H]
56 generalize in match H1;apply (nat_elim2 (?:? → ? → CProp) ??? x y);
58 [3: intros 2; simplify; apply q_lt_inj_plus_r; apply H;
59 apply (q_lt_canc_plus_r ?? (Qpos (\fst a))); apply H3;
60 |2: cases (?:False); simplify in H2;
61 apply (q_lt_le_incompat (sum_bases l1 (S n)) OQ);[2: apply sum_bases_ge_OQ;]
62 apply (q_lt_canc_plus_r ?? (Qpos (\fst a))); apply H2;
63 |1: cases n in H2; intro;
64 [1: cases (?:False); apply (q_lt_corefl ? H2);
65 |2: simplify; apply q_lt_plus_trans; [apply sum_bases_ge_OQ]
69 axiom q_minus_distrib:
70 ∀x,y,z:Q.x - (y + z) = x - y - z.
72 axiom q_le_OQ_Qpos: ∀x.OQ ≤ Qpos x.
74 lemma initial_shift_same_values:
75 ∀l1:q_f.∀init.init < start l1 →
77 (mk_q_f init (〈\fst (unpos (start l1 - init) ?),OQ〉:: bars l1)).
78 [apply hide; apply q_lt_minus; rewrite > q_plus_sym; rewrite > q_plus_OQ; assumption]
79 intros; generalize in ⊢ (? ? (? ? (? ? (? ? ? (? ? ? (? ? %)) ?) ?))); intro;
80 cases (unpos (start l1-init) H1); intro input;
81 simplify in ⊢ (? ? ? (? ? ? (? ? ? (? (? ? (? ? (? ? ? % ?) ?)) ?))));
82 cases (value (mk_q_f init (〈w,OQ〉::bars l1)) input);
83 simplify in ⊢ (? ? ? (? ? ? %));
84 cases (q_cmp input (start (mk_q_f init (〈w,OQ〉::bars l1)))) in H3;
85 whd in ⊢ (% → ?); simplify in H3;
86 [1: intro; cases H4; clear H4; rewrite > H3;
87 cases (value l1 init); simplify; cases (q_cmp init (start l1)) in H4;
88 [1: cases (?:False); apply (q_lt_corefl init); rewrite > H4 in ⊢ (?? %); apply H;
89 |3: cases (?:False); apply (q_lt_antisym init (start l1)); assumption;
90 |2: whd in ⊢ (% → ?); intro; rewrite > H8; clear H8 H4;
91 rewrite > H7; clear H7; rewrite > (?:\fst w1 = O); [reflexivity]
92 symmetry; apply le_n_O_to_eq;
93 rewrite > (sum_bases_O (mk_q_f init (〈w,OQ〉::bars l1)) (\fst w1)); [apply le_n]
94 clear H6 w2; simplify in H5:(? ? (? ? %));
95 destruct H3; rewrite > q_d_x_x in H5; assumption;]
96 |2: intros; cases (value l1 input); simplify in ⊢ (? ? (? ? ? %) ?);
97 cases (q_cmp input (start l1)) in H5; whd in ⊢ (% → ?);
98 [1: cases (?:False); clear w2 H4 w1 H2 w H1;
99 apply (q_lt_antisym init (start l1)); [assumption] rewrite < H5; assumption
100 |2: intros; rewrite > H6; clear H6; rewrite > H4; reflexivity;
101 |3: cases (?:False); apply (q_lt_antisym input (start l1)); [2: assumption]
102 apply (q_lt_trans ??? H3 H);]
103 |3: intro; cases H4; clear H4;
104 cases (value l1 input); simplify; cases (q_cmp input (start l1)) in H4; whd in ⊢ (% → ?);
105 [1: intro; cases H8; clear H8; rewrite > H11; rewrite > H7; clear H11 H7;
106 simplify in ⊢ (? ? ? (? ? ? (? ? % ? ?)));
107 cut (\fst w1 = S (\fst w2)) as Key; [rewrite > Key; reflexivity;]
108 cut (\fst w2 = O); [2: clear H10;
109 symmetry; apply le_n_O_to_eq; rewrite > (sum_bases_O l1 (\fst w2)); [apply le_n]
110 apply (q_le_trans ??? H9); rewrite < H4; rewrite > q_d_x_x;
111 apply q_eq_to_le; reflexivity;]
112 rewrite > Hcut; clear Hcut H10 H9; simplify in H5 H6;
113 cut (ⅆ[input,init] = Qpos w) as E; [2:
114 rewrite > H2; rewrite < H4; rewrite > q_d_sym;
115 rewrite > q_d_noabs; [reflexivity] apply q_lt_to_le; assumption;]
116 cases (\fst w1) in H5 H6; intros;
117 [1: cases (?:False); clear H5; simplify in H6;
118 apply (q_lt_corefl ⅆ[input,init]);
119 rewrite > E in ⊢ (??%); rewrite < q_plus_OQ in ⊢ (??%);
120 rewrite > q_plus_sym; assumption;
121 |2: cases n in H5 H6; [intros; reflexivity] intros;
122 cases (?:False); clear H6; cases (bars l1) in H5; simplify; intros;
123 [apply (q_pos_OQ one);|apply (q_pos_OQ (\fst b));]
124 apply (q_le_S ??? (sum_bases_ge_OQ ? n1));[apply []|3:apply l]
125 simplify in ⊢ (? (? (? % ?) ?) ?); rewrite < (q_plus_minus (Qpos w));
126 rewrite > q_elim_minus; apply q_le_minus_r;
127 rewrite > q_elim_opp; rewrite < E in ⊢ (??%); assumption;]
128 |2: intros; rewrite > H8; rewrite > H7; clear H8 H7;
129 simplify in H5 H6 ⊢ %;
130 cases (\fst w1) in H5 H6; [intros; reflexivity]
132 [1: intros; simplify; elim n [reflexivity] simplify; assumption;
133 |2: simplify; intros; cases (?:False); clear H6;
134 apply (q_lt_le_incompat (input - init) (Qpos w) );
135 [1: rewrite > H2; do 2 rewrite > q_elim_minus;
136 apply q_lt_plus; rewrite > q_elim_minus;
137 rewrite < q_plus_assoc; rewrite < q_elim_minus;
138 rewrite > q_plus_minus;rewrite > q_plus_OQ; assumption;
139 |2: rewrite < q_d_noabs; [2: apply q_lt_to_le; assumption]
140 rewrite > q_d_sym; apply (q_le_S ???? H5);apply sum_bases_ge_OQ;]]
141 |3: intro; cases H8; clear H8; rewrite > H11; rewrite > H7; clear H11 H7;
142 simplify in ⊢ (? ? ? (? ? ? (? ? % ? ?)));
143 cut (\fst w1 = S (\fst w2)) as Key; [rewrite > Key; reflexivity;]
145 cases (\fst w1) in H5 H6; intros;
146 [1: cases (?:False); clear H5 H9 H10; simplify in H6;
147 apply (q_lt_antisym input (start l1)); [2: assumption]
148 rewrite > q_d_sym in H6;
149 rewrite > q_d_noabs in H6; [2: apply q_lt_to_le; assumption]
150 rewrite > q_plus_sym in H6;
151 rewrite > q_plus_OQ in H6; rewrite > H2 in H6;
152 lapply (q_lt_plus ??? H6) as X; clear H6 H2 H3 H1 H H4 w1 w2 w;
153 rewrite > q_elim_minus in X; rewrite < q_plus_assoc in X;
154 rewrite > (q_plus_sym (Qopp init)) in X;
155 rewrite < q_elim_minus in X; rewrite > q_plus_minus in X;
156 rewrite > q_plus_OQ in X; assumption;
157 |2: simplify in H5; apply eq_f;
158 cut (sum_bases (bars l1) (\fst w2) < sum_bases (bars l1) (S n)+Qpos w);[2:
159 apply (q_le_lt_trans ??? H9);
160 apply (q_lt_trans ??? ? H6);
161 rewrite > q_d_sym; rewrite > q_d_noabs; [2:apply q_lt_to_le;assumption]
162 rewrite > q_d_sym; rewrite > q_d_noabs; [2:apply q_lt_to_le;assumption]
163 do 2 rewrite > q_elim_minus; rewrite > (q_plus_sym ? (Qopp init));
164 apply q_lt_plus; rewrite > q_plus_sym;
165 rewrite > q_elim_minus; rewrite < q_plus_assoc;
166 rewrite < q_elim_minus; rewrite > q_plus_minus;
167 rewrite > q_plus_OQ; apply q_lt_opp_opp; assumption]
169 cut (ⅆ[input,init] - Qpos w = ⅆ[input,start l1]);[2:
170 rewrite > q_d_sym; rewrite > q_d_noabs; [2:apply q_lt_to_le;assumption]
171 rewrite > q_d_sym; rewrite > q_d_noabs; [2:apply q_lt_to_le;assumption]
172 rewrite > H2; rewrite > (q_elim_minus (start ?));
173 rewrite > q_minus_distrib; rewrite > q_elim_opp;
174 do 2 rewrite > q_elim_minus;
175 do 2 rewrite < q_plus_assoc;
176 rewrite > (q_plus_sym ? init);
177 rewrite > (q_plus_assoc ? init);
178 rewrite > (q_plus_sym ? init);
179 rewrite < (q_elim_minus init); rewrite > q_plus_minus;
180 rewrite > (q_plus_sym OQ); rewrite > q_plus_OQ;
181 rewrite < q_elim_minus; reflexivity;]
182 cut (sum_bases (bars l1) n < sum_bases (bars l1) (S (\fst w2)));[2:
183 apply (q_le_lt_trans ???? H10); rewrite < Hcut1;
184 rewrite > q_elim_minus; apply q_le_minus_r; rewrite > q_elim_opp;
185 assumption;] clear Hcut1 H5 H10;
186 generalize in match Hcut;generalize in match Hcut2;clear Hcut Hcut2;
187 apply (nat_elim2 ???? n (\fst w2));
188 [3: intros (x y); apply eq_f; apply H5; clear H5;
189 [1: clear H7; apply sum_bases_lt_canc; assumption;
191 |2: intros; cases (?:False); clear H6;
192 cases n1 in H5; intro;
193 [1: apply (q_lt_corefl ? H5);
194 |2: cases (bars l1) in H5; intro;
196 apply (q_lt_le_incompat ?? (q_lt_canc_plus_r ??? H5));
197 apply q_le_plus_trans; [apply sum_bases_ge_OQ]
199 |2: simplify in H5:(??%);
200 lapply (q_lt_canc_plus_r (sum_bases l (S n2)) ?? H5) as X;
201 apply (q_lt_le_incompat ?? X); apply sum_bases_ge_OQ]]
202 |1: intro; cases n1 [intros; reflexivity] intros; cases (?:False);
207 [1: intro; elim n1; [reflexivity] cases (?:False);
211 elim n1 in H6; [reflexivity] cases (?:False);
212 [1: apply (q_lt_corefl ? H5);
213 |2: cases (bars l1) in H5; intro;
215 apply (q_lt_le_incompat ?? (q_lt_canc_plus_r ??? H5));
216 apply q_le_plus_trans; [apply sum_bases_ge_OQ]
218 |2: simplify in H5:(??%);
219 lapply (q_lt_canc_plus_r (sum_bases l (S n2)) ?? H5) as X;
220 apply (q_lt_le_incompat ?? X); apply sum_bases_ge_OQ]]
225 alias symbol "pi2" = "pair pi2".
226 alias symbol "pi1" = "pair pi1".
227 definition rebase_spec ≝
228 ∀l1,l2:q_f.∃p:q_f × q_f.
230 (*len (bars (\fst p)) = len (bars (\snd p))*)
231 (start (\fst p) = start (\snd p))
232 (same_bases (\fst p) (\snd p))
233 (same_values l1 (\fst p))
234 (same_values l2 (\snd p)).
236 definition rebase_spec_simpl ≝
237 λstart.λl1,l2:list bar.λp:(list bar) × (list bar).
239 (same_bases (mk_q_f start (\fst p)) (mk_q_f start (\snd p)))
240 (same_values (mk_q_f start l1) (mk_q_f start (\fst p)))
241 (same_values (mk_q_f start l2) (mk_q_f start (\snd p))).
243 (* a local letin makes russell fail *)
244 definition cb0h : list bar → list bar ≝
245 λl.mk_list (λi.〈\fst (nth l ▭ i),OQ〉) (len l).
248 λP.λp:∃x:(list bar) × (list bar).P x.match p with [ex_introT p _ ⇒ p].
250 definition inject ≝ λP.λp:(list bar) × (list bar).λh:P p. ex_introT ? P p h.
251 coercion inject with 0 1 nocomposites.
253 definition rebase: rebase_spec.
254 intros 2 (f1 f2); cases f1 (s1 l1); cases f2 (s2 l2); clear f1 f2;
256 λs.λl1,l2.λm.λz.len l1 + len l2 < m → rebase_spec_simpl s l1 l2 z);
257 alias symbol "pi1" (instance 34) = "exT \fst".
258 alias symbol "pi1" (instance 21) = "exT \fst".
260 let rec aux (l1,l2:list bar) (n:nat) on n : (list bar) × (list bar) ≝
262 [ O ⇒ 〈 nil ? , nil ? 〉
265 [ nil ⇒ 〈cb0h l2, l2〉
268 [ nil ⇒ 〈l1, cb0h l1〉
270 let base1 ≝ Qpos (\fst he1) in
271 let base2 ≝ Qpos (\fst he2) in
272 let height1 ≝ (\snd he1) in
273 let height2 ≝ (\snd he2) in
274 match q_cmp base1 base2 with
276 let rc ≝ aux tl1 tl2 m in
277 〈he1 :: \fst rc,he2 :: \snd rc〉
279 let rest ≝ base2 - base1 in
280 let rc ≝ aux tl1 (〈\fst (unpos rest ?),height2〉 :: tl2) m in
281 〈〈\fst he1,height1〉 :: \fst rc,〈\fst he1,height2〉 :: \snd rc〉
283 let rest ≝ base1 - base2 in
284 let rc ≝ aux (〈\fst (unpos rest ?),height1〉 :: tl1) tl2 m in
285 〈〈\fst he2,height1〉 :: \fst rc,〈\fst he2,height2〉 :: \snd rc〉
287 in aux : ∀l1,l2,m.∃z.∀s.spec s l1 l2 m z); unfold spec;
288 [9: clearbody aux; unfold spec in aux; clear spec;
290 [1: cases (aux l1 l2 (S (len l1 + len l2)));
291 cases (H1 s1 (le_n ?)); clear H1;
292 exists [apply 〈mk_q_f s1 (\fst w), mk_q_f s2 (\snd w)〉] split;
294 |3: intro; apply (H3 input);
295 |4: intro; rewrite > H in H4;
296 rewrite > (H4 input); reflexivity;]
297 |2: letin l2' ≝ (〈\fst (unpos (s2-s1) ?),OQ〉::l2);[
298 apply q_lt_minus; rewrite > q_plus_sym; rewrite > q_plus_OQ;
300 cases (aux l1 l2' (S (len l1 + len l2')));
301 cases (H1 s1 (le_n ?)); clear H1 aux;
302 exists [apply 〈mk_q_f s1 (\fst w), mk_q_f s1 (\snd w)〉] split;
306 |4: intro; rewrite < (H4 input); clear H3 H4 H2 w;
307 cases (value (mk_q_f s1 l2') input);
308 cases (q_cmp input (start (mk_q_f s1 l2'))) in H1;
310 [1: intros; cases H2; clear H2; whd in ⊢ (??? %);
311 cases (value (mk_q_f s2 l2) input);
312 cases (q_cmp input (start (mk_q_f s2 l2))) in H2;
314 [1: intros; cases H6; clear H6; change with (w1 = w);
317 |1,2: unfold rest; apply q_lt_minus; rewrite > q_plus_sym; rewrite > q_plus_OQ;
324 |8: intros; cases (?:False); apply (not_le_Sn_O ? H1);]