| 13673 |      1 | (*  Title:      HOL/MicroJava/Comp/AuxLemmas.thy
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|  |      2 |     ID:         $Id$
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|  |      3 |     Author:     Martin Strecker
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|  |      4 | *)
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|  |      5 | 
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|  |      6 | 
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|  |      7 | (* Auxiliary Lemmas *)
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|  |      8 | 
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| 15860 |      9 | theory AuxLemmas
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|  |     10 | imports "../J/JBasis"
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|  |     11 | begin
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| 13673 |     12 | 
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|  |     13 | (**********************************************************************)
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|  |     14 | (* List.thy *)
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|  |     15 | (**********************************************************************)
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|  |     16 | 
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|  |     17 | 
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|  |     18 | 
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|  |     19 | lemma app_nth_greater_len [rule_format (no_asm), simp]:
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|  |     20 |  "\<forall> ind. length pre \<le> ind \<longrightarrow> (pre @ a # post) ! (Suc ind) = (pre @ post) ! ind"
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|  |     21 | apply (induct "pre")
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|  |     22 | apply auto
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|  |     23 | apply (case_tac ind)
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|  |     24 | apply auto
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|  |     25 | done
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|  |     26 | 
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|  |     27 | lemma length_takeWhile: "v \<in> set xs \<Longrightarrow> length (takeWhile (%z. z~=v) xs) < length xs"
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|  |     28 | by (induct xs, auto)
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|  |     29 | 
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|  |     30 | lemma nth_length_takeWhile [simp]: 
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|  |     31 |   "v \<in> set xs \<Longrightarrow> xs ! (length (takeWhile (%z. z~=v) xs)) = v"
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|  |     32 | by (induct xs, auto)
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|  |     33 | 
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|  |     34 | 
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|  |     35 | lemma map_list_update [simp]:
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|  |     36 |   "\<lbrakk> x \<in> set xs; distinct xs\<rbrakk> \<Longrightarrow> 
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|  |     37 |   (map f xs) [length (takeWhile (\<lambda>z. z \<noteq> x) xs) := v] = 
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|  |     38 |   map (f(x:=v)) xs"
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|  |     39 | apply (induct xs)
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|  |     40 | apply simp
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|  |     41 | apply (case_tac "x=a")
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|  |     42 | apply auto
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|  |     43 | done
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|  |     44 | 
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|  |     45 | 
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|  |     46 | (**********************************************************************)
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|  |     47 | (* Product_Type.thy *)
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|  |     48 | (**********************************************************************)
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|  |     49 | 
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|  |     50 | 
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|  |     51 | lemma split_compose: "(split f) \<circ> (\<lambda> (a,b). ((fa a), (fb b))) =
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|  |     52 |   (\<lambda> (a,b). (f (fa a) (fb b)))"
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|  |     53 | by (simp add: split_def o_def)
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|  |     54 | 
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|  |     55 | lemma split_iter: "(\<lambda> (a,b,c). ((g1 a), (g2 b), (g3 c))) = 
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|  |     56 |         (\<lambda> (a,p). ((g1 a), (\<lambda> (b, c). ((g2 b), (g3 c))) p))"
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|  |     57 | by (simp add: split_def o_def)
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|  |     58 | 
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|  |     59 | 
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|  |     60 | (**********************************************************************)
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|  |     61 | (* Set.thy *)
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|  |     62 | (**********************************************************************)
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|  |     63 | 
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|  |     64 | lemma singleton_in_set: "A = {a} \<Longrightarrow> a \<in> A" by simp
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|  |     65 | 
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|  |     66 | (**********************************************************************)
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|  |     67 | (* Map.thy *)
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|  |     68 | (**********************************************************************)
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|  |     69 | 
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|  |     70 | lemma the_map_upd: "(the \<circ> f(x\<mapsto>v)) = (the \<circ> f)(x:=v)"
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|  |     71 | by (simp add: expand_fun_eq)
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|  |     72 | 
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|  |     73 | lemma map_of_in_set: 
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|  |     74 |   "(map_of xs x = None) = (x \<notin> set (map fst xs))"
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|  |     75 | by (induct xs, auto)
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|  |     76 | 
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|  |     77 | lemma map_map_upd [simp]: 
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|  |     78 |   "y \<notin> set xs \<Longrightarrow> map (the \<circ> f(y\<mapsto>v)) xs = map (the \<circ> f) xs"
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|  |     79 | by (simp add: the_map_upd)
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|  |     80 | 
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|  |     81 | lemma map_map_upds [rule_format (no_asm), simp]: 
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|  |     82 | "\<forall> f vs. (\<forall>y\<in>set ys. y \<notin> set xs) \<longrightarrow> map (the \<circ> f(ys[\<mapsto>]vs)) xs = map (the \<circ> f) xs"
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| 14025 |     83 | apply (induct xs)
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|  |     84 |  apply simp
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|  |     85 | apply fastsimp
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| 13673 |     86 | done
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|  |     87 | 
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|  |     88 | lemma map_upds_distinct [rule_format (no_asm), simp]: 
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|  |     89 |   "\<forall> f vs. length ys = length vs \<longrightarrow> distinct ys \<longrightarrow> map (the \<circ> f(ys[\<mapsto>]vs)) ys = vs"
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|  |     90 | apply (induct ys)
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|  |     91 | apply simp
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|  |     92 | apply (intro strip)
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|  |     93 | apply (case_tac vs)
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|  |     94 | apply simp
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| 14025 |     95 | apply (simp only: map_upds_Cons distinct.simps hd.simps tl.simps map.simps)
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| 13673 |     96 | apply clarify
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| 14025 |     97 | apply (simp del: o_apply)
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| 13673 |     98 | apply simp
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|  |     99 | done
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|  |    100 | 
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|  |    101 | 
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|  |    102 | lemma map_of_map_as_map_upd [rule_format (no_asm)]: "distinct (map f zs) \<longrightarrow> 
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|  |    103 | map_of (map (\<lambda> p. (f p, g p)) zs) = empty (map f zs [\<mapsto>] map g zs)"
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|  |    104 | by (induct zs, auto)
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|  |    105 | 
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|  |    106 | (* In analogy to Map.map_of_SomeD *)
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|  |    107 | lemma map_upds_SomeD [rule_format (no_asm)]: 
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|  |    108 |   "\<forall> m ys. (m(xs[\<mapsto>]ys)) k = Some y \<longrightarrow> k \<in> (set xs) \<or> (m k = Some y)"
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|  |    109 | apply (induct xs)
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|  |    110 | apply simp
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| 14025 |    111 | apply auto
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|  |    112 | apply(case_tac ys)
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| 13673 |    113 | apply auto
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|  |    114 | done
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|  |    115 | 
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|  |    116 | lemma map_of_upds_SomeD: "(map_of m (xs[\<mapsto>]ys)) k = Some y 
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|  |    117 |   \<Longrightarrow> k \<in> (set (xs @ map fst m))"
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|  |    118 | by (auto dest: map_upds_SomeD map_of_SomeD fst_in_set_lemma)
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|  |    119 | 
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|  |    120 | 
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|  |    121 | lemma map_of_map_prop [rule_format (no_asm)]: 
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|  |    122 |   "(map_of (map f xs) k = Some v) \<longrightarrow> 
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|  |    123 |   (\<forall> x \<in> set xs. (P1 x)) \<longrightarrow> 
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|  |    124 |   (\<forall> x. (P1 x) \<longrightarrow> (P2 (f x))) \<longrightarrow>
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|  |    125 |   (P2(k, v))"
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|  |    126 | by (induct xs,auto)
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|  |    127 | 
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|  |    128 | lemma map_of_map2: "\<forall> x \<in> set xs. (fst (f x)) = (fst x) \<Longrightarrow>
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|  |    129 |   map_of (map f xs) a = option_map (\<lambda> b. (snd (f (a, b)))) (map_of xs a)"
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|  |    130 | by (induct xs, auto)
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|  |    131 | 
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|  |    132 | lemma option_map_of [simp]: "(option_map f (map_of xs k) = None) = ((map_of xs k) = None)"
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|  |    133 | by (simp add: option_map_def split: option.split)
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|  |    134 | 
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|  |    135 | 
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|  |    136 | 
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|  |    137 | end
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