src/HOL/Complete_Lattice.thy
 author haftmann Sun Jul 10 14:14:19 2011 +0200 (2011-07-10) changeset 43739 4529a3c56609 parent 42284 326f57825e1a child 43740 3316e6831801 permissions -rw-r--r--
more succinct proofs
     1 (*  Author:     Tobias Nipkow, Lawrence C Paulson and Markus Wenzel; Florian Haftmann, TU Muenchen *)

     2

     3 header {* Complete lattices, with special focus on sets *}

     4

     5 theory Complete_Lattice

     6 imports Set

     7 begin

     8

     9 notation

    10   less_eq (infix "\<sqsubseteq>" 50) and

    11   less (infix "\<sqsubset>" 50) and

    12   inf (infixl "\<sqinter>" 70) and

    13   sup (infixl "\<squnion>" 65) and

    14   top ("\<top>") and

    15   bot ("\<bottom>")

    16

    17

    18 subsection {* Syntactic infimum and supremum operations *}

    19

    20 class Inf =

    21   fixes Inf :: "'a set \<Rightarrow> 'a" ("\<Sqinter>_" [900] 900)

    22

    23 class Sup =

    24   fixes Sup :: "'a set \<Rightarrow> 'a" ("\<Squnion>_" [900] 900)

    25

    26 subsection {* Abstract complete lattices *}

    27

    28 class complete_lattice = bounded_lattice + Inf + Sup +

    29   assumes Inf_lower: "x \<in> A \<Longrightarrow> \<Sqinter>A \<sqsubseteq> x"

    30      and Inf_greatest: "(\<And>x. x \<in> A \<Longrightarrow> z \<sqsubseteq> x) \<Longrightarrow> z \<sqsubseteq> \<Sqinter>A"

    31   assumes Sup_upper: "x \<in> A \<Longrightarrow> x \<sqsubseteq> \<Squnion>A"

    32      and Sup_least: "(\<And>x. x \<in> A \<Longrightarrow> x \<sqsubseteq> z) \<Longrightarrow> \<Squnion>A \<sqsubseteq> z"

    33 begin

    34

    35 lemma dual_complete_lattice:

    36   "class.complete_lattice Sup Inf (op \<ge>) (op >) (op \<squnion>) (op \<sqinter>) \<top> \<bottom>"

    37   by (auto intro!: class.complete_lattice.intro dual_bounded_lattice)

    38     (unfold_locales, (fact bot_least top_greatest

    39         Sup_upper Sup_least Inf_lower Inf_greatest)+)

    40

    41 lemma Inf_Sup: "\<Sqinter>A = \<Squnion>{b. \<forall>a \<in> A. b \<sqsubseteq> a}"

    42   by (auto intro: antisym Inf_lower Inf_greatest Sup_upper Sup_least)

    43

    44 lemma Sup_Inf:  "\<Squnion>A = \<Sqinter>{b. \<forall>a \<in> A. a \<sqsubseteq> b}"

    45   by (auto intro: antisym Inf_lower Inf_greatest Sup_upper Sup_least)

    46

    47 lemma Inf_empty [simp]:

    48   "\<Sqinter>{} = \<top>"

    49   by (auto intro: antisym Inf_greatest)

    50

    51 lemma Sup_empty [simp]:

    52   "\<Squnion>{} = \<bottom>"

    53   by (auto intro: antisym Sup_least)

    54

    55 lemma Inf_UNIV [simp]:

    56   "\<Sqinter>UNIV = \<bottom>"

    57   by (simp add: Sup_Inf Sup_empty [symmetric])

    58

    59 lemma Sup_UNIV [simp]:

    60   "\<Squnion>UNIV = \<top>"

    61   by (simp add: Inf_Sup Inf_empty [symmetric])

    62

    63 lemma Inf_insert: "\<Sqinter>insert a A = a \<sqinter> \<Sqinter>A"

    64   by (auto intro: le_infI le_infI1 le_infI2 antisym Inf_greatest Inf_lower)

    65

    66 lemma Sup_insert: "\<Squnion>insert a A = a \<squnion> \<Squnion>A"

    67   by (auto intro: le_supI le_supI1 le_supI2 antisym Sup_least Sup_upper)

    68

    69 lemma Inf_singleton [simp]:

    70   "\<Sqinter>{a} = a"

    71   by (auto intro: antisym Inf_lower Inf_greatest)

    72

    73 lemma Sup_singleton [simp]:

    74   "\<Squnion>{a} = a"

    75   by (auto intro: antisym Sup_upper Sup_least)

    76

    77 lemma Inf_binary:

    78   "\<Sqinter>{a, b} = a \<sqinter> b"

    79   by (simp add: Inf_empty Inf_insert)

    80

    81 lemma Sup_binary:

    82   "\<Squnion>{a, b} = a \<squnion> b"

    83   by (simp add: Sup_empty Sup_insert)

    84

    85 lemma le_Inf_iff: "b \<sqsubseteq> Inf A \<longleftrightarrow> (\<forall>a\<in>A. b \<sqsubseteq> a)"

    86   by (auto intro: Inf_greatest dest: Inf_lower)

    87

    88 lemma Sup_le_iff: "Sup A \<sqsubseteq> b \<longleftrightarrow> (\<forall>a\<in>A. a \<sqsubseteq> b)"

    89   by (auto intro: Sup_least dest: Sup_upper)

    90

    91 lemma Inf_mono:

    92   assumes "\<And>b. b \<in> B \<Longrightarrow> \<exists>a\<in>A. a \<sqsubseteq> b"

    93   shows "Inf A \<sqsubseteq> Inf B"

    94 proof (rule Inf_greatest)

    95   fix b assume "b \<in> B"

    96   with assms obtain a where "a \<in> A" and "a \<sqsubseteq> b" by blast

    97   from a \<in> A have "Inf A \<sqsubseteq> a" by (rule Inf_lower)

    98   with a \<sqsubseteq> b show "Inf A \<sqsubseteq> b" by auto

    99 qed

   100

   101 lemma Sup_mono:

   102   assumes "\<And>a. a \<in> A \<Longrightarrow> \<exists>b\<in>B. a \<sqsubseteq> b"

   103   shows "Sup A \<sqsubseteq> Sup B"

   104 proof (rule Sup_least)

   105   fix a assume "a \<in> A"

   106   with assms obtain b where "b \<in> B" and "a \<sqsubseteq> b" by blast

   107   from b \<in> B have "b \<sqsubseteq> Sup B" by (rule Sup_upper)

   108   with a \<sqsubseteq> b show "a \<sqsubseteq> Sup B" by auto

   109 qed

   110

   111 lemma top_le:

   112   "top \<sqsubseteq> x \<Longrightarrow> x = top"

   113   by (rule antisym) auto

   114

   115 lemma le_bot:

   116   "x \<sqsubseteq> bot \<Longrightarrow> x = bot"

   117   by (rule antisym) auto

   118

   119 lemma not_less_bot[simp]: "\<not> (x \<sqsubset> bot)"

   120   using bot_least[of x] by (auto simp: le_less)

   121

   122 lemma not_top_less[simp]: "\<not> (top \<sqsubset> x)"

   123   using top_greatest[of x] by (auto simp: le_less)

   124

   125 lemma Sup_upper2: "u \<in> A \<Longrightarrow> v \<sqsubseteq> u \<Longrightarrow> v \<sqsubseteq> Sup A"

   126   using Sup_upper[of u A] by auto

   127

   128 lemma Inf_lower2: "u \<in> A \<Longrightarrow> u \<sqsubseteq> v \<Longrightarrow> Inf A \<sqsubseteq> v"

   129   using Inf_lower[of u A] by auto

   130

   131 definition INFI :: "'b set \<Rightarrow> ('b \<Rightarrow> 'a) \<Rightarrow> 'a" where

   132   "INFI A f = \<Sqinter> (f  A)"

   133

   134 definition SUPR :: "'b set \<Rightarrow> ('b \<Rightarrow> 'a) \<Rightarrow> 'a" where

   135   "SUPR A f = \<Squnion> (f  A)"

   136

   137 end

   138

   139 syntax

   140   "_INF1"     :: "pttrns \<Rightarrow> 'b \<Rightarrow> 'b"           ("(3INF _./ _)" [0, 10] 10)

   141   "_INF"      :: "pttrn \<Rightarrow> 'a set \<Rightarrow> 'b \<Rightarrow> 'b"  ("(3INF _:_./ _)" [0, 0, 10] 10)

   142   "_SUP1"     :: "pttrns \<Rightarrow> 'b \<Rightarrow> 'b"           ("(3SUP _./ _)" [0, 10] 10)

   143   "_SUP"      :: "pttrn \<Rightarrow> 'a set \<Rightarrow> 'b \<Rightarrow> 'b"  ("(3SUP _:_./ _)" [0, 0, 10] 10)

   144

   145 syntax (xsymbols)

   146   "_INF1"     :: "pttrns \<Rightarrow> 'b \<Rightarrow> 'b"           ("(3\<Sqinter>_./ _)" [0, 10] 10)

   147   "_INF"      :: "pttrn \<Rightarrow> 'a set \<Rightarrow> 'b \<Rightarrow> 'b"  ("(3\<Sqinter>_\<in>_./ _)" [0, 0, 10] 10)

   148   "_SUP1"     :: "pttrns \<Rightarrow> 'b \<Rightarrow> 'b"           ("(3\<Squnion>_./ _)" [0, 10] 10)

   149   "_SUP"      :: "pttrn \<Rightarrow> 'a set \<Rightarrow> 'b \<Rightarrow> 'b"  ("(3\<Squnion>_\<in>_./ _)" [0, 0, 10] 10)

   150

   151 translations

   152   "INF x y. B"   == "INF x. INF y. B"

   153   "INF x. B"     == "CONST INFI CONST UNIV (%x. B)"

   154   "INF x. B"     == "INF x:CONST UNIV. B"

   155   "INF x:A. B"   == "CONST INFI A (%x. B)"

   156   "SUP x y. B"   == "SUP x. SUP y. B"

   157   "SUP x. B"     == "CONST SUPR CONST UNIV (%x. B)"

   158   "SUP x. B"     == "SUP x:CONST UNIV. B"

   159   "SUP x:A. B"   == "CONST SUPR A (%x. B)"

   160

   161 print_translation {*

   162   [Syntax_Trans.preserve_binder_abs2_tr' @{const_syntax INFI} @{syntax_const "_INF"},

   163     Syntax_Trans.preserve_binder_abs2_tr' @{const_syntax SUPR} @{syntax_const "_SUP"}]

   164 *} -- {* to avoid eta-contraction of body *}

   165

   166 context complete_lattice

   167 begin

   168

   169 lemma SUP_cong: "(\<And>x. x \<in> A \<Longrightarrow> f x = g x) \<Longrightarrow> SUPR A f = SUPR A g"

   170   by (simp add: SUPR_def cong: image_cong)

   171

   172 lemma INF_cong: "(\<And>x. x \<in> A \<Longrightarrow> f x = g x) \<Longrightarrow> INFI A f = INFI A g"

   173   by (simp add: INFI_def cong: image_cong)

   174

   175 lemma le_SUPI: "i : A \<Longrightarrow> M i \<sqsubseteq> (SUP i:A. M i)"

   176   by (auto simp add: SUPR_def intro: Sup_upper)

   177

   178 lemma le_SUPI2: "i \<in> A \<Longrightarrow> u \<sqsubseteq> M i \<Longrightarrow> u \<sqsubseteq> (SUP i:A. M i)"

   179   using le_SUPI[of i A M] by auto

   180

   181 lemma SUP_leI: "(\<And>i. i : A \<Longrightarrow> M i \<sqsubseteq> u) \<Longrightarrow> (SUP i:A. M i) \<sqsubseteq> u"

   182   by (auto simp add: SUPR_def intro: Sup_least)

   183

   184 lemma INF_leI: "i : A \<Longrightarrow> (INF i:A. M i) \<sqsubseteq> M i"

   185   by (auto simp add: INFI_def intro: Inf_lower)

   186

   187 lemma INF_leI2: "i \<in> A \<Longrightarrow> M i \<sqsubseteq> u \<Longrightarrow> (INF i:A. M i) \<sqsubseteq> u"

   188   using INF_leI[of i A M] by auto

   189

   190 lemma le_INFI: "(\<And>i. i : A \<Longrightarrow> u \<sqsubseteq> M i) \<Longrightarrow> u \<sqsubseteq> (INF i:A. M i)"

   191   by (auto simp add: INFI_def intro: Inf_greatest)

   192

   193 lemma SUP_le_iff: "(SUP i:A. M i) \<sqsubseteq> u \<longleftrightarrow> (\<forall>i \<in> A. M i \<sqsubseteq> u)"

   194   unfolding SUPR_def by (auto simp add: Sup_le_iff)

   195

   196 lemma le_INF_iff: "u \<sqsubseteq> (INF i:A. M i) \<longleftrightarrow> (\<forall>i \<in> A. u \<sqsubseteq> M i)"

   197   unfolding INFI_def by (auto simp add: le_Inf_iff)

   198

   199 lemma INF_const[simp]: "A \<noteq> {} \<Longrightarrow> (INF i:A. M) = M"

   200   by (auto intro: antisym INF_leI le_INFI)

   201

   202 lemma SUP_const[simp]: "A \<noteq> {} \<Longrightarrow> (SUP i:A. M) = M"

   203   by (auto intro: antisym SUP_leI le_SUPI)

   204

   205 lemma INF_mono:

   206   "(\<And>m. m \<in> B \<Longrightarrow> \<exists>n\<in>A. f n \<le> g m) \<Longrightarrow> (INF n:A. f n) \<le> (INF n:B. g n)"

   207   by (force intro!: Inf_mono simp: INFI_def)

   208

   209 lemma SUP_mono:

   210   "(\<And>n. n \<in> A \<Longrightarrow> \<exists>m\<in>B. f n \<le> g m) \<Longrightarrow> (SUP n:A. f n) \<le> (SUP n:B. g n)"

   211   by (force intro!: Sup_mono simp: SUPR_def)

   212

   213 lemma INF_subset:  "A \<subseteq> B \<Longrightarrow> INFI B f \<le> INFI A f"

   214   by (intro INF_mono) auto

   215

   216 lemma SUP_subset:  "A \<subseteq> B \<Longrightarrow> SUPR A f \<le> SUPR B f"

   217   by (intro SUP_mono) auto

   218

   219 lemma INF_commute: "(INF i:A. INF j:B. f i j) = (INF j:B. INF i:A. f i j)"

   220   by (iprover intro: INF_leI le_INFI order_trans antisym)

   221

   222 lemma SUP_commute: "(SUP i:A. SUP j:B. f i j) = (SUP j:B. SUP i:A. f i j)"

   223   by (iprover intro: SUP_leI le_SUPI order_trans antisym)

   224

   225 end

   226

   227 lemma Inf_less_iff:

   228   fixes a :: "'a\<Colon>{complete_lattice,linorder}"

   229   shows "Inf S < a \<longleftrightarrow> (\<exists>x\<in>S. x < a)"

   230   unfolding not_le[symmetric] le_Inf_iff by auto

   231

   232 lemma less_Sup_iff:

   233   fixes a :: "'a\<Colon>{complete_lattice,linorder}"

   234   shows "a < Sup S \<longleftrightarrow> (\<exists>x\<in>S. a < x)"

   235   unfolding not_le[symmetric] Sup_le_iff by auto

   236

   237 lemma INF_less_iff:

   238   fixes a :: "'a::{complete_lattice,linorder}"

   239   shows "(INF i:A. f i) < a \<longleftrightarrow> (\<exists>x\<in>A. f x < a)"

   240   unfolding INFI_def Inf_less_iff by auto

   241

   242 lemma less_SUP_iff:

   243   fixes a :: "'a::{complete_lattice,linorder}"

   244   shows "a < (SUP i:A. f i) \<longleftrightarrow> (\<exists>x\<in>A. a < f x)"

   245   unfolding SUPR_def less_Sup_iff by auto

   246

   247 subsection {* @{typ bool} and @{typ "_ \<Rightarrow> _"} as complete lattice *}

   248

   249 instantiation bool :: complete_lattice

   250 begin

   251

   252 definition

   253   "\<Sqinter>A \<longleftrightarrow> (\<forall>x\<in>A. x)"

   254

   255 definition

   256   "\<Squnion>A \<longleftrightarrow> (\<exists>x\<in>A. x)"

   257

   258 instance proof

   259 qed (auto simp add: Inf_bool_def Sup_bool_def le_bool_def)

   260

   261 end

   262

   263 lemma INFI_bool_eq [simp]:

   264   "INFI = Ball"

   265 proof (rule ext)+

   266   fix A :: "'a set"

   267   fix P :: "'a \<Rightarrow> bool"

   268   show "(INF x:A. P x) \<longleftrightarrow> (\<forall>x \<in> A. P x)"

   269     by (auto simp add: Ball_def INFI_def Inf_bool_def)

   270 qed

   271

   272 lemma SUPR_bool_eq [simp]:

   273   "SUPR = Bex"

   274 proof (rule ext)+

   275   fix A :: "'a set"

   276   fix P :: "'a \<Rightarrow> bool"

   277   show "(SUP x:A. P x) \<longleftrightarrow> (\<exists>x \<in> A. P x)"

   278     by (auto simp add: Bex_def SUPR_def Sup_bool_def)

   279 qed

   280

   281 instantiation "fun" :: (type, complete_lattice) complete_lattice

   282 begin

   283

   284 definition

   285   "\<Sqinter>A = (\<lambda>x. \<Sqinter>{y. \<exists>f\<in>A. y = f x})"

   286

   287 lemma Inf_apply:

   288   "(\<Sqinter>A) x = \<Sqinter>{y. \<exists>f\<in>A. y = f x}"

   289   by (simp add: Inf_fun_def)

   290

   291 definition

   292   "\<Squnion>A = (\<lambda>x. \<Squnion>{y. \<exists>f\<in>A. y = f x})"

   293

   294 lemma Sup_apply:

   295   "(\<Squnion>A) x = \<Squnion>{y. \<exists>f\<in>A. y = f x}"

   296   by (simp add: Sup_fun_def)

   297

   298 instance proof

   299 qed (auto simp add: le_fun_def Inf_apply Sup_apply

   300   intro: Inf_lower Sup_upper Inf_greatest Sup_least)

   301

   302 end

   303

   304 lemma INFI_apply:

   305   "(\<Sqinter>y\<in>A. f y) x = (\<Sqinter>y\<in>A. f y x)"

   306   by (auto intro: arg_cong [of _ _ Inf] simp add: INFI_def Inf_apply)

   307

   308 lemma SUPR_apply:

   309   "(\<Squnion>y\<in>A. f y) x = (\<Squnion>y\<in>A. f y x)"

   310   by (auto intro: arg_cong [of _ _ Sup] simp add: SUPR_def Sup_apply)

   311

   312

   313 subsection {* Inter *}

   314

   315 abbreviation Inter :: "'a set set \<Rightarrow> 'a set" where

   316   "Inter S \<equiv> \<Sqinter>S"

   317

   318 notation (xsymbols)

   319   Inter  ("\<Inter>_" [90] 90)

   320

   321 lemma Inter_eq:

   322   "\<Inter>A = {x. \<forall>B \<in> A. x \<in> B}"

   323 proof (rule set_eqI)

   324   fix x

   325   have "(\<forall>Q\<in>{P. \<exists>B\<in>A. P \<longleftrightarrow> x \<in> B}. Q) \<longleftrightarrow> (\<forall>B\<in>A. x \<in> B)"

   326     by auto

   327   then show "x \<in> \<Inter>A \<longleftrightarrow> x \<in> {x. \<forall>B \<in> A. x \<in> B}"

   328     by (simp add: Inf_fun_def Inf_bool_def) (simp add: mem_def)

   329 qed

   330

   331 lemma Inter_iff [simp,no_atp]: "(A : Inter C) = (ALL X:C. A:X)"

   332   by (unfold Inter_eq) blast

   333

   334 lemma InterI [intro!]: "(!!X. X:C ==> A:X) ==> A : Inter C"

   335   by (simp add: Inter_eq)

   336

   337 text {*

   338   \medskip A destruct'' rule -- every @{term X} in @{term C}

   339   contains @{term A} as an element, but @{prop "A:X"} can hold when

   340   @{prop "X:C"} does not!  This rule is analogous to @{text spec}.

   341 *}

   342

   343 lemma InterD [elim, Pure.elim]: "A : Inter C ==> X:C ==> A:X"

   344   by auto

   345

   346 lemma InterE [elim]: "A : Inter C ==> (X~:C ==> R) ==> (A:X ==> R) ==> R"

   347   -- {* Classical'' elimination rule -- does not require proving

   348     @{prop "X:C"}. *}

   349   by (unfold Inter_eq) blast

   350

   351 lemma Inter_lower: "B \<in> A ==> Inter A \<subseteq> B"

   352   by blast

   353

   354 lemma Inter_subset:

   355   "[| !!X. X \<in> A ==> X \<subseteq> B; A ~= {} |] ==> \<Inter>A \<subseteq> B"

   356   by blast

   357

   358 lemma Inter_greatest: "(!!X. X \<in> A ==> C \<subseteq> X) ==> C \<subseteq> Inter A"

   359   by (iprover intro: InterI subsetI dest: subsetD)

   360

   361 lemma Int_eq_Inter: "A \<inter> B = \<Inter>{A, B}"

   362   by (fact Inf_binary [symmetric])

   363

   364 lemma Inter_empty [simp]: "\<Inter>{} = UNIV"

   365   by (fact Inf_empty)

   366

   367 lemma Inter_UNIV [simp]: "\<Inter>UNIV = {}"

   368   by (fact Inf_UNIV)

   369

   370 lemma Inter_insert [simp]: "\<Inter>(insert a B) = a \<inter> \<Inter>B"

   371   by (fact Inf_insert)

   372

   373 lemma Inter_Un_subset: "\<Inter>A \<union> \<Inter>B \<subseteq> \<Inter>(A \<inter> B)"

   374   by blast

   375

   376 lemma Inter_Un_distrib: "\<Inter>(A \<union> B) = \<Inter>A \<inter> \<Inter>B"

   377   by blast

   378

   379 lemma Inter_UNIV_conv [simp,no_atp]:

   380   "(\<Inter>A = UNIV) = (\<forall>x\<in>A. x = UNIV)"

   381   "(UNIV = \<Inter>A) = (\<forall>x\<in>A. x = UNIV)"

   382   by blast+

   383

   384 lemma Inter_anti_mono: "B \<subseteq> A ==> \<Inter>A \<subseteq> \<Inter>B"

   385   by blast

   386

   387

   388 subsection {* Intersections of families *}

   389

   390 abbreviation INTER :: "'a set \<Rightarrow> ('a \<Rightarrow> 'b set) \<Rightarrow> 'b set" where

   391   "INTER \<equiv> INFI"

   392

   393 syntax

   394   "_INTER1"     :: "pttrns => 'b set => 'b set"           ("(3INT _./ _)" [0, 10] 10)

   395   "_INTER"      :: "pttrn => 'a set => 'b set => 'b set"  ("(3INT _:_./ _)" [0, 0, 10] 10)

   396

   397 syntax (xsymbols)

   398   "_INTER1"     :: "pttrns => 'b set => 'b set"           ("(3\<Inter>_./ _)" [0, 10] 10)

   399   "_INTER"      :: "pttrn => 'a set => 'b set => 'b set"  ("(3\<Inter>_\<in>_./ _)" [0, 0, 10] 10)

   400

   401 syntax (latex output)

   402   "_INTER1"     :: "pttrns => 'b set => 'b set"           ("(3\<Inter>(00\<^bsub>_\<^esub>)/ _)" [0, 10] 10)

   403   "_INTER"      :: "pttrn => 'a set => 'b set => 'b set"  ("(3\<Inter>(00\<^bsub>_\<in>_\<^esub>)/ _)" [0, 0, 10] 10)

   404

   405 translations

   406   "INT x y. B"  == "INT x. INT y. B"

   407   "INT x. B"    == "CONST INTER CONST UNIV (%x. B)"

   408   "INT x. B"    == "INT x:CONST UNIV. B"

   409   "INT x:A. B"  == "CONST INTER A (%x. B)"

   410

   411 print_translation {*

   412   [Syntax_Trans.preserve_binder_abs2_tr' @{const_syntax INTER} @{syntax_const "_INTER"}]

   413 *} -- {* to avoid eta-contraction of body *}

   414

   415 lemma INTER_eq_Inter_image:

   416   "(\<Inter>x\<in>A. B x) = \<Inter>(BA)"

   417   by (fact INFI_def)

   418

   419 lemma Inter_def:

   420   "\<Inter>S = (\<Inter>x\<in>S. x)"

   421   by (simp add: INTER_eq_Inter_image image_def)

   422

   423 lemma INTER_def:

   424   "(\<Inter>x\<in>A. B x) = {y. \<forall>x\<in>A. y \<in> B x}"

   425   by (auto simp add: INTER_eq_Inter_image Inter_eq)

   426

   427 lemma Inter_image_eq [simp]:

   428   "\<Inter>(BA) = (\<Inter>x\<in>A. B x)"

   429   by (rule sym) (fact INTER_eq_Inter_image)

   430

   431 lemma INT_iff [simp]: "(b: (INT x:A. B x)) = (ALL x:A. b: B x)"

   432   by (unfold INTER_def) blast

   433

   434 lemma INT_I [intro!]: "(!!x. x:A ==> b: B x) ==> b : (INT x:A. B x)"

   435   by (unfold INTER_def) blast

   436

   437 lemma INT_D [elim, Pure.elim]: "b : (INT x:A. B x) ==> a:A ==> b: B a"

   438   by auto

   439

   440 lemma INT_E [elim]: "b : (INT x:A. B x) ==> (b: B a ==> R) ==> (a~:A ==> R) ==> R"

   441   -- {* "Classical" elimination -- by the Excluded Middle on @{prop "a:A"}. *}

   442   by (unfold INTER_def) blast

   443

   444 lemma INT_cong [cong]:

   445     "A = B ==> (!!x. x:B ==> C x = D x) ==> (INT x:A. C x) = (INT x:B. D x)"

   446   by (simp add: INTER_def)

   447

   448 lemma Collect_ball_eq: "{x. \<forall>y\<in>A. P x y} = (\<Inter>y\<in>A. {x. P x y})"

   449   by blast

   450

   451 lemma Collect_all_eq: "{x. \<forall>y. P x y} = (\<Inter>y. {x. P x y})"

   452   by blast

   453

   454 lemma INT_lower: "a \<in> A ==> (\<Inter>x\<in>A. B x) \<subseteq> B a"

   455   by (fact INF_leI)

   456

   457 lemma INT_greatest: "(!!x. x \<in> A ==> C \<subseteq> B x) ==> C \<subseteq> (\<Inter>x\<in>A. B x)"

   458   by (fact le_INFI)

   459

   460 lemma INT_empty [simp]: "(\<Inter>x\<in>{}. B x) = UNIV"

   461   by blast

   462

   463 lemma INT_absorb: "k \<in> I ==> A k \<inter> (\<Inter>i\<in>I. A i) = (\<Inter>i\<in>I. A i)"

   464   by blast

   465

   466 lemma INT_subset_iff: "(B \<subseteq> (\<Inter>i\<in>I. A i)) = (\<forall>i\<in>I. B \<subseteq> A i)"

   467   by (fact le_INF_iff)

   468

   469 lemma INT_insert [simp]: "(\<Inter>x \<in> insert a A. B x) = B a \<inter> INTER A B"

   470   by blast

   471

   472 lemma INT_Un: "(\<Inter>i \<in> A \<union> B. M i) = (\<Inter>i \<in> A. M i) \<inter> (\<Inter>i\<in>B. M i)"

   473   by blast

   474

   475 lemma INT_insert_distrib:

   476     "u \<in> A ==> (\<Inter>x\<in>A. insert a (B x)) = insert a (\<Inter>x\<in>A. B x)"

   477   by blast

   478

   479 lemma INT_constant [simp]: "(\<Inter>y\<in>A. c) = (if A = {} then UNIV else c)"

   480   by auto

   481

   482 lemma INT_eq: "(\<Inter>x\<in>A. B x) = \<Inter>({Y. \<exists>x\<in>A. Y = B x})"

   483   -- {* Look: it has an \emph{existential} quantifier *}

   484   by blast

   485

   486 lemma INTER_UNIV_conv[simp]:

   487  "(UNIV = (INT x:A. B x)) = (\<forall>x\<in>A. B x = UNIV)"

   488  "((INT x:A. B x) = UNIV) = (\<forall>x\<in>A. B x = UNIV)"

   489 by blast+

   490

   491 lemma INT_bool_eq: "(\<Inter>b::bool. A b) = (A True \<inter> A False)"

   492   by (auto intro: bool_induct)

   493

   494 lemma Pow_INT_eq: "Pow (\<Inter>x\<in>A. B x) = (\<Inter>x\<in>A. Pow (B x))"

   495   by blast

   496

   497 lemma INT_anti_mono:

   498   "B \<subseteq> A ==> (!!x. x \<in> A ==> f x \<subseteq> g x) ==>

   499     (\<Inter>x\<in>A. f x) \<subseteq> (\<Inter>x\<in>A. g x)"

   500   -- {* The last inclusion is POSITIVE! *}

   501   by (blast dest: subsetD)

   502

   503 lemma vimage_INT: "f-(INT x:A. B x) = (INT x:A. f - B x)"

   504   by blast

   505

   506

   507 subsection {* Union *}

   508

   509 abbreviation Union :: "'a set set \<Rightarrow> 'a set" where

   510   "Union S \<equiv> \<Squnion>S"

   511

   512 notation (xsymbols)

   513   Union  ("\<Union>_" [90] 90)

   514

   515 lemma Union_eq:

   516   "\<Union>A = {x. \<exists>B \<in> A. x \<in> B}"

   517 proof (rule set_eqI)

   518   fix x

   519   have "(\<exists>Q\<in>{P. \<exists>B\<in>A. P \<longleftrightarrow> x \<in> B}. Q) \<longleftrightarrow> (\<exists>B\<in>A. x \<in> B)"

   520     by auto

   521   then show "x \<in> \<Union>A \<longleftrightarrow> x \<in> {x. \<exists>B\<in>A. x \<in> B}"

   522     by (simp add: Sup_fun_def Sup_bool_def) (simp add: mem_def)

   523 qed

   524

   525 lemma Union_iff [simp, no_atp]:

   526   "A \<in> \<Union>C \<longleftrightarrow> (\<exists>X\<in>C. A\<in>X)"

   527   by (unfold Union_eq) blast

   528

   529 lemma UnionI [intro]:

   530   "X \<in> C \<Longrightarrow> A \<in> X \<Longrightarrow> A \<in> \<Union>C"

   531   -- {* The order of the premises presupposes that @{term C} is rigid;

   532     @{term A} may be flexible. *}

   533   by auto

   534

   535 lemma UnionE [elim!]:

   536   "A \<in> \<Union>C \<Longrightarrow> (\<And>X. A\<in>X \<Longrightarrow> X\<in>C \<Longrightarrow> R) \<Longrightarrow> R"

   537   by auto

   538

   539 lemma Union_upper: "B \<in> A ==> B \<subseteq> Union A"

   540   by (iprover intro: subsetI UnionI)

   541

   542 lemma Union_least: "(!!X. X \<in> A ==> X \<subseteq> C) ==> Union A \<subseteq> C"

   543   by (iprover intro: subsetI elim: UnionE dest: subsetD)

   544

   545 lemma Un_eq_Union: "A \<union> B = \<Union>{A, B}"

   546   by blast

   547

   548 lemma Union_empty [simp]: "Union({}) = {}"

   549   by blast

   550

   551 lemma Union_UNIV [simp]: "Union UNIV = UNIV"

   552   by blast

   553

   554 lemma Union_insert [simp]: "Union (insert a B) = a \<union> \<Union>B"

   555   by blast

   556

   557 lemma Union_Un_distrib [simp]: "\<Union>(A Un B) = \<Union>A \<union> \<Union>B"

   558   by blast

   559

   560 lemma Union_Int_subset: "\<Union>(A \<inter> B) \<subseteq> \<Union>A \<inter> \<Union>B"

   561   by blast

   562

   563 lemma Union_empty_conv [simp,no_atp]: "(\<Union>A = {}) = (\<forall>x\<in>A. x = {})"

   564   by blast

   565

   566 lemma empty_Union_conv [simp,no_atp]: "({} = \<Union>A) = (\<forall>x\<in>A. x = {})"

   567   by blast

   568

   569 lemma Union_disjoint: "(\<Union>C \<inter> A = {}) = (\<forall>B\<in>C. B \<inter> A = {})"

   570   by blast

   571

   572 lemma subset_Pow_Union: "A \<subseteq> Pow (\<Union>A)"

   573   by blast

   574

   575 lemma Union_Pow_eq [simp]: "\<Union>(Pow A) = A"

   576   by blast

   577

   578 lemma Union_mono: "A \<subseteq> B ==> \<Union>A \<subseteq> \<Union>B"

   579   by blast

   580

   581

   582 subsection {* Unions of families *}

   583

   584 abbreviation UNION :: "'a set \<Rightarrow> ('a \<Rightarrow> 'b set) \<Rightarrow> 'b set" where

   585   "UNION \<equiv> SUPR"

   586

   587 syntax

   588   "_UNION1"     :: "pttrns => 'b set => 'b set"           ("(3UN _./ _)" [0, 10] 10)

   589   "_UNION"      :: "pttrn => 'a set => 'b set => 'b set"  ("(3UN _:_./ _)" [0, 0, 10] 10)

   590

   591 syntax (xsymbols)

   592   "_UNION1"     :: "pttrns => 'b set => 'b set"           ("(3\<Union>_./ _)" [0, 10] 10)

   593   "_UNION"      :: "pttrn => 'a set => 'b set => 'b set"  ("(3\<Union>_\<in>_./ _)" [0, 0, 10] 10)

   594

   595 syntax (latex output)

   596   "_UNION1"     :: "pttrns => 'b set => 'b set"           ("(3\<Union>(00\<^bsub>_\<^esub>)/ _)" [0, 10] 10)

   597   "_UNION"      :: "pttrn => 'a set => 'b set => 'b set"  ("(3\<Union>(00\<^bsub>_\<in>_\<^esub>)/ _)" [0, 0, 10] 10)

   598

   599 translations

   600   "UN x y. B"   == "UN x. UN y. B"

   601   "UN x. B"     == "CONST UNION CONST UNIV (%x. B)"

   602   "UN x. B"     == "UN x:CONST UNIV. B"

   603   "UN x:A. B"   == "CONST UNION A (%x. B)"

   604

   605 text {*

   606   Note the difference between ordinary xsymbol syntax of indexed

   607   unions and intersections (e.g.\ @{text"\<Union>a\<^isub>1\<in>A\<^isub>1. B"})

   608   and their \LaTeX\ rendition: @{term"\<Union>a\<^isub>1\<in>A\<^isub>1. B"}. The

   609   former does not make the index expression a subscript of the

   610   union/intersection symbol because this leads to problems with nested

   611   subscripts in Proof General.

   612 *}

   613

   614 print_translation {*

   615   [Syntax_Trans.preserve_binder_abs2_tr' @{const_syntax UNION} @{syntax_const "_UNION"}]

   616 *} -- {* to avoid eta-contraction of body *}

   617

   618 lemma UNION_eq_Union_image:

   619   "(\<Union>x\<in>A. B x) = \<Union>(BA)"

   620   by (fact SUPR_def)

   621

   622 lemma Union_def:

   623   "\<Union>S = (\<Union>x\<in>S. x)"

   624   by (simp add: UNION_eq_Union_image image_def)

   625

   626 lemma UNION_def [no_atp]:

   627   "(\<Union>x\<in>A. B x) = {y. \<exists>x\<in>A. y \<in> B x}"

   628   by (auto simp add: UNION_eq_Union_image Union_eq)

   629

   630 lemma Union_image_eq [simp]:

   631   "\<Union>(BA) = (\<Union>x\<in>A. B x)"

   632   by (rule sym) (fact UNION_eq_Union_image)

   633

   634 lemma UN_iff [simp]: "(b: (UN x:A. B x)) = (EX x:A. b: B x)"

   635   by (unfold UNION_def) blast

   636

   637 lemma UN_I [intro]: "a:A ==> b: B a ==> b: (UN x:A. B x)"

   638   -- {* The order of the premises presupposes that @{term A} is rigid;

   639     @{term b} may be flexible. *}

   640   by auto

   641

   642 lemma UN_E [elim!]: "b : (UN x:A. B x) ==> (!!x. x:A ==> b: B x ==> R) ==> R"

   643   by (unfold UNION_def) blast

   644

   645 lemma UN_cong [cong]:

   646     "A = B ==> (!!x. x:B ==> C x = D x) ==> (UN x:A. C x) = (UN x:B. D x)"

   647   by (simp add: UNION_def)

   648

   649 lemma strong_UN_cong:

   650     "A = B ==> (!!x. x:B =simp=> C x = D x) ==> (UN x:A. C x) = (UN x:B. D x)"

   651   by (simp add: UNION_def simp_implies_def)

   652

   653 lemma image_eq_UN: "fA = (UN x:A. {f x})"

   654   by blast

   655

   656 lemma UN_upper: "a \<in> A ==> B a \<subseteq> (\<Union>x\<in>A. B x)"

   657   by (fact le_SUPI)

   658

   659 lemma UN_least: "(!!x. x \<in> A ==> B x \<subseteq> C) ==> (\<Union>x\<in>A. B x) \<subseteq> C"

   660   by (iprover intro: subsetI elim: UN_E dest: subsetD)

   661

   662 lemma Collect_bex_eq [no_atp]: "{x. \<exists>y\<in>A. P x y} = (\<Union>y\<in>A. {x. P x y})"

   663   by blast

   664

   665 lemma UN_insert_distrib: "u \<in> A ==> (\<Union>x\<in>A. insert a (B x)) = insert a (\<Union>x\<in>A. B x)"

   666   by blast

   667

   668 lemma UN_empty [simp,no_atp]: "(\<Union>x\<in>{}. B x) = {}"

   669   by blast

   670

   671 lemma UN_empty2 [simp]: "(\<Union>x\<in>A. {}) = {}"

   672   by blast

   673

   674 lemma UN_singleton [simp]: "(\<Union>x\<in>A. {x}) = A"

   675   by blast

   676

   677 lemma UN_absorb: "k \<in> I ==> A k \<union> (\<Union>i\<in>I. A i) = (\<Union>i\<in>I. A i)"

   678   by auto

   679

   680 lemma UN_insert [simp]: "(\<Union>x\<in>insert a A. B x) = B a \<union> UNION A B"

   681   by blast

   682

   683 lemma UN_Un[simp]: "(\<Union>i \<in> A \<union> B. M i) = (\<Union>i\<in>A. M i) \<union> (\<Union>i\<in>B. M i)"

   684   by blast

   685

   686 lemma UN_UN_flatten: "(\<Union>x \<in> (\<Union>y\<in>A. B y). C x) = (\<Union>y\<in>A. \<Union>x\<in>B y. C x)"

   687   by blast

   688

   689 lemma UN_subset_iff: "((\<Union>i\<in>I. A i) \<subseteq> B) = (\<forall>i\<in>I. A i \<subseteq> B)"

   690   by (fact SUP_le_iff)

   691

   692 lemma image_Union: "f  \<Union>S = (\<Union>x\<in>S. f  x)"

   693   by blast

   694

   695 lemma UN_constant [simp]: "(\<Union>y\<in>A. c) = (if A = {} then {} else c)"

   696   by auto

   697

   698 lemma UN_eq: "(\<Union>x\<in>A. B x) = \<Union>({Y. \<exists>x\<in>A. Y = B x})"

   699   by blast

   700

   701 lemma UNION_empty_conv[simp]:

   702   "({} = (UN x:A. B x)) = (\<forall>x\<in>A. B x = {})"

   703   "((UN x:A. B x) = {}) = (\<forall>x\<in>A. B x = {})"

   704 by blast+

   705

   706 lemma Collect_ex_eq [no_atp]: "{x. \<exists>y. P x y} = (\<Union>y. {x. P x y})"

   707   by blast

   708

   709 lemma ball_UN: "(\<forall>z \<in> UNION A B. P z) = (\<forall>x\<in>A. \<forall>z \<in> B x. P z)"

   710   by blast

   711

   712 lemma bex_UN: "(\<exists>z \<in> UNION A B. P z) = (\<exists>x\<in>A. \<exists>z\<in>B x. P z)"

   713   by blast

   714

   715 lemma Un_eq_UN: "A \<union> B = (\<Union>b. if b then A else B)"

   716   by (auto simp add: split_if_mem2)

   717

   718 lemma UN_bool_eq: "(\<Union>b::bool. A b) = (A True \<union> A False)"

   719   by (auto intro: bool_contrapos)

   720

   721 lemma UN_Pow_subset: "(\<Union>x\<in>A. Pow (B x)) \<subseteq> Pow (\<Union>x\<in>A. B x)"

   722   by blast

   723

   724 lemma UN_mono:

   725   "A \<subseteq> B ==> (!!x. x \<in> A ==> f x \<subseteq> g x) ==>

   726     (\<Union>x\<in>A. f x) \<subseteq> (\<Union>x\<in>B. g x)"

   727   by (blast dest: subsetD)

   728

   729 lemma vimage_Union: "f - (Union A) = (UN X:A. f - X)"

   730   by blast

   731

   732 lemma vimage_UN: "f-(UN x:A. B x) = (UN x:A. f - B x)"

   733   by blast

   734

   735 lemma vimage_eq_UN: "f-B = (UN y: B. f-{y})"

   736   -- {* NOT suitable for rewriting *}

   737   by blast

   738

   739 lemma image_UN: "(f  (UNION A B)) = (UN x:A.(f  (B x)))"

   740 by blast

   741

   742

   743 subsection {* Distributive laws *}

   744

   745 lemma Int_Union: "A \<inter> \<Union>B = (\<Union>C\<in>B. A \<inter> C)"

   746   by blast

   747

   748 lemma Int_Union2: "\<Union>B \<inter> A = (\<Union>C\<in>B. C \<inter> A)"

   749   by blast

   750

   751 lemma Un_Union_image: "(\<Union>x\<in>C. A x \<union> B x) = \<Union>(AC) \<union> \<Union>(BC)"

   752   -- {* Devlin, Fundamentals of Contemporary Set Theory, page 12, exercise 5: *}

   753   -- {* Union of a family of unions *}

   754   by blast

   755

   756 lemma UN_Un_distrib: "(\<Union>i\<in>I. A i \<union> B i) = (\<Union>i\<in>I. A i) \<union> (\<Union>i\<in>I. B i)"

   757   -- {* Equivalent version *}

   758   by blast

   759

   760 lemma Un_Inter: "A \<union> \<Inter>B = (\<Inter>C\<in>B. A \<union> C)"

   761   by blast

   762

   763 lemma Int_Inter_image: "(\<Inter>x\<in>C. A x \<inter> B x) = \<Inter>(AC) \<inter> \<Inter>(BC)"

   764   by blast

   765

   766 lemma INT_Int_distrib: "(\<Inter>i\<in>I. A i \<inter> B i) = (\<Inter>i\<in>I. A i) \<inter> (\<Inter>i\<in>I. B i)"

   767   -- {* Equivalent version *}

   768   by blast

   769

   770 lemma Int_UN_distrib: "B \<inter> (\<Union>i\<in>I. A i) = (\<Union>i\<in>I. B \<inter> A i)"

   771   -- {* Halmos, Naive Set Theory, page 35. *}

   772   by blast

   773

   774 lemma Un_INT_distrib: "B \<union> (\<Inter>i\<in>I. A i) = (\<Inter>i\<in>I. B \<union> A i)"

   775   by blast

   776

   777 lemma Int_UN_distrib2: "(\<Union>i\<in>I. A i) \<inter> (\<Union>j\<in>J. B j) = (\<Union>i\<in>I. \<Union>j\<in>J. A i \<inter> B j)"

   778   by blast

   779

   780 lemma Un_INT_distrib2: "(\<Inter>i\<in>I. A i) \<union> (\<Inter>j\<in>J. B j) = (\<Inter>i\<in>I. \<Inter>j\<in>J. A i \<union> B j)"

   781   by blast

   782

   783

   784 subsection {* Complement *}

   785

   786 lemma Compl_UN [simp]: "-(\<Union>x\<in>A. B x) = (\<Inter>x\<in>A. -B x)"

   787   by blast

   788

   789 lemma Compl_INT [simp]: "-(\<Inter>x\<in>A. B x) = (\<Union>x\<in>A. -B x)"

   790   by blast

   791

   792

   793 subsection {* Miniscoping and maxiscoping *}

   794

   795 text {* \medskip Miniscoping: pushing in quantifiers and big Unions

   796            and Intersections. *}

   797

   798 lemma UN_simps [simp]:

   799   "!!a B C. (UN x:C. insert a (B x)) = (if C={} then {} else insert a (UN x:C. B x))"

   800   "!!A B C. (UN x:C. A x Un B)   = ((if C={} then {} else (UN x:C. A x) Un B))"

   801   "!!A B C. (UN x:C. A Un B x)   = ((if C={} then {} else A Un (UN x:C. B x)))"

   802   "!!A B C. (UN x:C. A x Int B)  = ((UN x:C. A x) Int B)"

   803   "!!A B C. (UN x:C. A Int B x)  = (A Int (UN x:C. B x))"

   804   "!!A B C. (UN x:C. A x - B)    = ((UN x:C. A x) - B)"

   805   "!!A B C. (UN x:C. A - B x)    = (A - (INT x:C. B x))"

   806   "!!A B. (UN x: Union A. B x) = (UN y:A. UN x:y. B x)"

   807   "!!A B C. (UN z: UNION A B. C z) = (UN  x:A. UN z: B(x). C z)"

   808   "!!A B f. (UN x:fA. B x)     = (UN a:A. B (f a))"

   809   by auto

   810

   811 lemma INT_simps [simp]:

   812   "!!A B C. (INT x:C. A x Int B) = (if C={} then UNIV else (INT x:C. A x) Int B)"

   813   "!!A B C. (INT x:C. A Int B x) = (if C={} then UNIV else A Int (INT x:C. B x))"

   814   "!!A B C. (INT x:C. A x - B)   = (if C={} then UNIV else (INT x:C. A x) - B)"

   815   "!!A B C. (INT x:C. A - B x)   = (if C={} then UNIV else A - (UN x:C. B x))"

   816   "!!a B C. (INT x:C. insert a (B x)) = insert a (INT x:C. B x)"

   817   "!!A B C. (INT x:C. A x Un B)  = ((INT x:C. A x) Un B)"

   818   "!!A B C. (INT x:C. A Un B x)  = (A Un (INT x:C. B x))"

   819   "!!A B. (INT x: Union A. B x) = (INT y:A. INT x:y. B x)"

   820   "!!A B C. (INT z: UNION A B. C z) = (INT x:A. INT z: B(x). C z)"

   821   "!!A B f. (INT x:fA. B x)    = (INT a:A. B (f a))"

   822   by auto

   823

   824 lemma ball_simps [simp,no_atp]:

   825   "!!A P Q. (ALL x:A. P x | Q) = ((ALL x:A. P x) | Q)"

   826   "!!A P Q. (ALL x:A. P | Q x) = (P | (ALL x:A. Q x))"

   827   "!!A P Q. (ALL x:A. P --> Q x) = (P --> (ALL x:A. Q x))"

   828   "!!A P Q. (ALL x:A. P x --> Q) = ((EX x:A. P x) --> Q)"

   829   "!!P. (ALL x:{}. P x) = True"

   830   "!!P. (ALL x:UNIV. P x) = (ALL x. P x)"

   831   "!!a B P. (ALL x:insert a B. P x) = (P a & (ALL x:B. P x))"

   832   "!!A P. (ALL x:Union A. P x) = (ALL y:A. ALL x:y. P x)"

   833   "!!A B P. (ALL x: UNION A B. P x) = (ALL a:A. ALL x: B a. P x)"

   834   "!!P Q. (ALL x:Collect Q. P x) = (ALL x. Q x --> P x)"

   835   "!!A P f. (ALL x:fA. P x) = (ALL x:A. P (f x))"

   836   "!!A P. (~(ALL x:A. P x)) = (EX x:A. ~P x)"

   837   by auto

   838

   839 lemma bex_simps [simp,no_atp]:

   840   "!!A P Q. (EX x:A. P x & Q) = ((EX x:A. P x) & Q)"

   841   "!!A P Q. (EX x:A. P & Q x) = (P & (EX x:A. Q x))"

   842   "!!P. (EX x:{}. P x) = False"

   843   "!!P. (EX x:UNIV. P x) = (EX x. P x)"

   844   "!!a B P. (EX x:insert a B. P x) = (P(a) | (EX x:B. P x))"

   845   "!!A P. (EX x:Union A. P x) = (EX y:A. EX x:y. P x)"

   846   "!!A B P. (EX x: UNION A B. P x) = (EX a:A. EX x:B a. P x)"

   847   "!!P Q. (EX x:Collect Q. P x) = (EX x. Q x & P x)"

   848   "!!A P f. (EX x:fA. P x) = (EX x:A. P (f x))"

   849   "!!A P. (~(EX x:A. P x)) = (ALL x:A. ~P x)"

   850   by auto

   851

   852 lemma ball_conj_distrib:

   853   "(ALL x:A. P x & Q x) = ((ALL x:A. P x) & (ALL x:A. Q x))"

   854   by blast

   855

   856 lemma bex_disj_distrib:

   857   "(EX x:A. P x | Q x) = ((EX x:A. P x) | (EX x:A. Q x))"

   858   by blast

   859

   860

   861 text {* \medskip Maxiscoping: pulling out big Unions and Intersections. *}

   862

   863 lemma UN_extend_simps:

   864   "!!a B C. insert a (UN x:C. B x) = (if C={} then {a} else (UN x:C. insert a (B x)))"

   865   "!!A B C. (UN x:C. A x) Un B    = (if C={} then B else (UN x:C. A x Un B))"

   866   "!!A B C. A Un (UN x:C. B x)   = (if C={} then A else (UN x:C. A Un B x))"

   867   "!!A B C. ((UN x:C. A x) Int B) = (UN x:C. A x Int B)"

   868   "!!A B C. (A Int (UN x:C. B x)) = (UN x:C. A Int B x)"

   869   "!!A B C. ((UN x:C. A x) - B) = (UN x:C. A x - B)"

   870   "!!A B C. (A - (INT x:C. B x)) = (UN x:C. A - B x)"

   871   "!!A B. (UN y:A. UN x:y. B x) = (UN x: Union A. B x)"

   872   "!!A B C. (UN  x:A. UN z: B(x). C z) = (UN z: UNION A B. C z)"

   873   "!!A B f. (UN a:A. B (f a)) = (UN x:fA. B x)"

   874   by auto

   875

   876 lemma INT_extend_simps:

   877   "!!A B C. (INT x:C. A x) Int B = (if C={} then B else (INT x:C. A x Int B))"

   878   "!!A B C. A Int (INT x:C. B x) = (if C={} then A else (INT x:C. A Int B x))"

   879   "!!A B C. (INT x:C. A x) - B   = (if C={} then UNIV-B else (INT x:C. A x - B))"

   880   "!!A B C. A - (UN x:C. B x)   = (if C={} then A else (INT x:C. A - B x))"

   881   "!!a B C. insert a (INT x:C. B x) = (INT x:C. insert a (B x))"

   882   "!!A B C. ((INT x:C. A x) Un B)  = (INT x:C. A x Un B)"

   883   "!!A B C. A Un (INT x:C. B x)  = (INT x:C. A Un B x)"

   884   "!!A B. (INT y:A. INT x:y. B x) = (INT x: Union A. B x)"

   885   "!!A B C. (INT x:A. INT z: B(x). C z) = (INT z: UNION A B. C z)"

   886   "!!A B f. (INT a:A. B (f a))    = (INT x:fA. B x)"

   887   by auto

   888

   889

   890 no_notation

   891   less_eq  (infix "\<sqsubseteq>" 50) and

   892   less (infix "\<sqsubset>" 50) and

   893   bot ("\<bottom>") and

   894   top ("\<top>") and

   895   inf  (infixl "\<sqinter>" 70) and

   896   sup  (infixl "\<squnion>" 65) and

   897   Inf  ("\<Sqinter>_" [900] 900) and

   898   Sup  ("\<Squnion>_" [900] 900)

   899

   900 no_syntax (xsymbols)

   901   "_INF1"     :: "pttrns \<Rightarrow> 'b \<Rightarrow> 'b"           ("(3\<Sqinter>_./ _)" [0, 10] 10)

   902   "_INF"      :: "pttrn \<Rightarrow> 'a set \<Rightarrow> 'b \<Rightarrow> 'b"  ("(3\<Sqinter>_\<in>_./ _)" [0, 0, 10] 10)

   903   "_SUP1"     :: "pttrns \<Rightarrow> 'b \<Rightarrow> 'b"           ("(3\<Squnion>_./ _)" [0, 10] 10)

   904   "_SUP"      :: "pttrn \<Rightarrow> 'a set \<Rightarrow> 'b \<Rightarrow> 'b"  ("(3\<Squnion>_\<in>_./ _)" [0, 0, 10] 10)

   905

   906 lemmas mem_simps =

   907   insert_iff empty_iff Un_iff Int_iff Compl_iff Diff_iff

   908   mem_Collect_eq UN_iff Union_iff INT_iff Inter_iff

   909   -- {* Each of these has ALREADY been added @{text "[simp]"} above. *}

   910

   911 end
`