author | haftmann |
Sat, 25 Jan 2014 23:50:49 +0100 | |
changeset 55147 | bce3dbc11f95 |
parent 54538 | ba7392b52a7c |
permissions | -rw-r--r-- |
54538
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
1 |
(* Title: HOL/List_Prefix.thy |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
2 |
Author: Tobias Nipkow and Markus Wenzel, TU Muenchen |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
3 |
Author: Christian Sternagel, JAIST |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
4 |
*) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
5 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
6 |
header {* Parallel lists, list suffixes, and homeomorphic embedding *} |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
7 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
8 |
theory List_Prefix |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
9 |
imports List |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
10 |
begin |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
11 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
12 |
subsection {* Prefix order on lists *} |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
13 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
14 |
definition prefixeq :: "'a list \<Rightarrow> 'a list \<Rightarrow> bool" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
15 |
where "prefixeq xs ys \<longleftrightarrow> (\<exists>zs. ys = xs @ zs)" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
16 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
17 |
definition prefix :: "'a list \<Rightarrow> 'a list \<Rightarrow> bool" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
18 |
where "prefix xs ys \<longleftrightarrow> prefixeq xs ys \<and> xs \<noteq> ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
19 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
20 |
interpretation prefix_order: order prefixeq prefix |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
21 |
by default (auto simp: prefixeq_def prefix_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
22 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
23 |
interpretation prefix_bot: order_bot Nil prefixeq prefix |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
24 |
by default (simp add: prefixeq_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
25 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
26 |
lemma prefixeqI [intro?]: "ys = xs @ zs \<Longrightarrow> prefixeq xs ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
27 |
unfolding prefixeq_def by blast |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
28 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
29 |
lemma prefixeqE [elim?]: |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
30 |
assumes "prefixeq xs ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
31 |
obtains zs where "ys = xs @ zs" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
32 |
using assms unfolding prefixeq_def by blast |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
33 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
34 |
lemma prefixI' [intro?]: "ys = xs @ z # zs \<Longrightarrow> prefix xs ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
35 |
unfolding prefix_def prefixeq_def by blast |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
36 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
37 |
lemma prefixE' [elim?]: |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
38 |
assumes "prefix xs ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
39 |
obtains z zs where "ys = xs @ z # zs" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
40 |
proof - |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
41 |
from `prefix xs ys` obtain us where "ys = xs @ us" and "xs \<noteq> ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
42 |
unfolding prefix_def prefixeq_def by blast |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
43 |
with that show ?thesis by (auto simp add: neq_Nil_conv) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
44 |
qed |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
45 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
46 |
lemma prefixI [intro?]: "prefixeq xs ys \<Longrightarrow> xs \<noteq> ys \<Longrightarrow> prefix xs ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
47 |
unfolding prefix_def by blast |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
48 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
49 |
lemma prefixE [elim?]: |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
50 |
fixes xs ys :: "'a list" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
51 |
assumes "prefix xs ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
52 |
obtains "prefixeq xs ys" and "xs \<noteq> ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
53 |
using assms unfolding prefix_def by blast |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
54 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
55 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
56 |
subsection {* Basic properties of prefixes *} |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
57 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
58 |
theorem Nil_prefixeq [iff]: "prefixeq [] xs" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
59 |
by (simp add: prefixeq_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
60 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
61 |
theorem prefixeq_Nil [simp]: "(prefixeq xs []) = (xs = [])" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
62 |
by (induct xs) (simp_all add: prefixeq_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
63 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
64 |
lemma prefixeq_snoc [simp]: "prefixeq xs (ys @ [y]) \<longleftrightarrow> xs = ys @ [y] \<or> prefixeq xs ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
65 |
proof |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
66 |
assume "prefixeq xs (ys @ [y])" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
67 |
then obtain zs where zs: "ys @ [y] = xs @ zs" .. |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
68 |
show "xs = ys @ [y] \<or> prefixeq xs ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
69 |
by (metis append_Nil2 butlast_append butlast_snoc prefixeqI zs) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
70 |
next |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
71 |
assume "xs = ys @ [y] \<or> prefixeq xs ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
72 |
then show "prefixeq xs (ys @ [y])" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
73 |
by (metis prefix_order.eq_iff prefix_order.order_trans prefixeqI) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
74 |
qed |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
75 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
76 |
lemma Cons_prefixeq_Cons [simp]: "prefixeq (x # xs) (y # ys) = (x = y \<and> prefixeq xs ys)" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
77 |
by (auto simp add: prefixeq_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
78 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
79 |
lemma prefixeq_code [code]: |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
80 |
"prefixeq [] xs \<longleftrightarrow> True" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
81 |
"prefixeq (x # xs) [] \<longleftrightarrow> False" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
82 |
"prefixeq (x # xs) (y # ys) \<longleftrightarrow> x = y \<and> prefixeq xs ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
83 |
by simp_all |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
84 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
85 |
lemma same_prefixeq_prefixeq [simp]: "prefixeq (xs @ ys) (xs @ zs) = prefixeq ys zs" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
86 |
by (induct xs) simp_all |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
87 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
88 |
lemma same_prefixeq_nil [iff]: "prefixeq (xs @ ys) xs = (ys = [])" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
89 |
by (metis append_Nil2 append_self_conv prefix_order.eq_iff prefixeqI) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
90 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
91 |
lemma prefixeq_prefixeq [simp]: "prefixeq xs ys \<Longrightarrow> prefixeq xs (ys @ zs)" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
92 |
by (metis prefix_order.le_less_trans prefixeqI prefixE prefixI) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
93 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
94 |
lemma append_prefixeqD: "prefixeq (xs @ ys) zs \<Longrightarrow> prefixeq xs zs" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
95 |
by (auto simp add: prefixeq_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
96 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
97 |
theorem prefixeq_Cons: "prefixeq xs (y # ys) = (xs = [] \<or> (\<exists>zs. xs = y # zs \<and> prefixeq zs ys))" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
98 |
by (cases xs) (auto simp add: prefixeq_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
99 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
100 |
theorem prefixeq_append: |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
101 |
"prefixeq xs (ys @ zs) = (prefixeq xs ys \<or> (\<exists>us. xs = ys @ us \<and> prefixeq us zs))" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
102 |
apply (induct zs rule: rev_induct) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
103 |
apply force |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
104 |
apply (simp del: append_assoc add: append_assoc [symmetric]) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
105 |
apply (metis append_eq_appendI) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
106 |
done |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
107 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
108 |
lemma append_one_prefixeq: |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
109 |
"prefixeq xs ys \<Longrightarrow> length xs < length ys \<Longrightarrow> prefixeq (xs @ [ys ! length xs]) ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
110 |
proof (unfold prefixeq_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
111 |
assume a1: "\<exists>zs. ys = xs @ zs" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
112 |
then obtain sk :: "'a list" where sk: "ys = xs @ sk" by fastforce |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
113 |
assume a2: "length xs < length ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
114 |
have f1: "\<And>v. ([]\<Colon>'a list) @ v = v" using append_Nil2 by simp |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
115 |
have "[] \<noteq> sk" using a1 a2 sk less_not_refl by force |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
116 |
hence "\<exists>v. xs @ hd sk # v = ys" using sk by (metis hd_Cons_tl) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
117 |
thus "\<exists>zs. ys = (xs @ [ys ! length xs]) @ zs" using f1 by fastforce |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
118 |
qed |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
119 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
120 |
theorem prefixeq_length_le: "prefixeq xs ys \<Longrightarrow> length xs \<le> length ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
121 |
by (auto simp add: prefixeq_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
122 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
123 |
lemma prefixeq_same_cases: |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
124 |
"prefixeq (xs\<^sub>1::'a list) ys \<Longrightarrow> prefixeq xs\<^sub>2 ys \<Longrightarrow> prefixeq xs\<^sub>1 xs\<^sub>2 \<or> prefixeq xs\<^sub>2 xs\<^sub>1" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
125 |
unfolding prefixeq_def by (force simp: append_eq_append_conv2) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
126 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
127 |
lemma set_mono_prefixeq: "prefixeq xs ys \<Longrightarrow> set xs \<subseteq> set ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
128 |
by (auto simp add: prefixeq_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
129 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
130 |
lemma take_is_prefixeq: "prefixeq (take n xs) xs" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
131 |
unfolding prefixeq_def by (metis append_take_drop_id) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
132 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
133 |
lemma map_prefixeqI: "prefixeq xs ys \<Longrightarrow> prefixeq (map f xs) (map f ys)" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
134 |
by (auto simp: prefixeq_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
135 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
136 |
lemma prefixeq_length_less: "prefix xs ys \<Longrightarrow> length xs < length ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
137 |
by (auto simp: prefix_def prefixeq_def) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
138 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
139 |
lemma prefix_simps [simp, code]: |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
140 |
"prefix xs [] \<longleftrightarrow> False" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
141 |
"prefix [] (x # xs) \<longleftrightarrow> True" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
142 |
"prefix (x # xs) (y # ys) \<longleftrightarrow> x = y \<and> prefix xs ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
143 |
by (simp_all add: prefix_def cong: conj_cong) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
144 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
145 |
lemma take_prefix: "prefix xs ys \<Longrightarrow> prefix (take n xs) ys" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
146 |
apply (induct n arbitrary: xs ys) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
147 |
apply (case_tac ys, simp_all)[1] |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
148 |
apply (metis prefix_order.less_trans prefixI take_is_prefixeq) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
149 |
done |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
150 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
151 |
lemma not_prefixeq_cases: |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
152 |
assumes pfx: "\<not> prefixeq ps ls" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
153 |
obtains |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
154 |
(c1) "ps \<noteq> []" and "ls = []" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
155 |
| (c2) a as x xs where "ps = a#as" and "ls = x#xs" and "x = a" and "\<not> prefixeq as xs" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
156 |
| (c3) a as x xs where "ps = a#as" and "ls = x#xs" and "x \<noteq> a" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
157 |
proof (cases ps) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
158 |
case Nil |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
159 |
then show ?thesis using pfx by simp |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
160 |
next |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
161 |
case (Cons a as) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
162 |
note c = `ps = a#as` |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
163 |
show ?thesis |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
164 |
proof (cases ls) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
165 |
case Nil then show ?thesis by (metis append_Nil2 pfx c1 same_prefixeq_nil) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
166 |
next |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
167 |
case (Cons x xs) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
168 |
show ?thesis |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
169 |
proof (cases "x = a") |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
170 |
case True |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
171 |
have "\<not> prefixeq as xs" using pfx c Cons True by simp |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
172 |
with c Cons True show ?thesis by (rule c2) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
173 |
next |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
174 |
case False |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
175 |
with c Cons show ?thesis by (rule c3) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
176 |
qed |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
177 |
qed |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
178 |
qed |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
179 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
180 |
lemma not_prefixeq_induct [consumes 1, case_names Nil Neq Eq]: |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
181 |
assumes np: "\<not> prefixeq ps ls" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
182 |
and base: "\<And>x xs. P (x#xs) []" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
183 |
and r1: "\<And>x xs y ys. x \<noteq> y \<Longrightarrow> P (x#xs) (y#ys)" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
184 |
and r2: "\<And>x xs y ys. \<lbrakk> x = y; \<not> prefixeq xs ys; P xs ys \<rbrakk> \<Longrightarrow> P (x#xs) (y#ys)" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
185 |
shows "P ps ls" using np |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
186 |
proof (induct ls arbitrary: ps) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
187 |
case Nil then show ?case |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
188 |
by (auto simp: neq_Nil_conv elim!: not_prefixeq_cases intro!: base) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
189 |
next |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
190 |
case (Cons y ys) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
191 |
then have npfx: "\<not> prefixeq ps (y # ys)" by simp |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
192 |
then obtain x xs where pv: "ps = x # xs" |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
193 |
by (rule not_prefixeq_cases) auto |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
194 |
show ?case by (metis Cons.hyps Cons_prefixeq_Cons npfx pv r1 r2) |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
195 |
qed |
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
196 |
|
ba7392b52a7c
factor 'List_Prefix' out of 'Sublist' and move to 'Main' (needed for codatatypes)
blanchet
parents:
diff
changeset
|
197 |
end |