src/HOL/Enum.thy
author nipkow
Thu Jun 12 18:47:16 2014 +0200 (2014-06-12)
changeset 57247 8191ccf6a1bd
parent 55088 57c82e01022b
child 57818 51aa30c9ee4e
permissions -rw-r--r--
added [simp]
     1 (* Author: Florian Haftmann, TU Muenchen *)
     2 
     3 header {* Finite types as explicit enumerations *}
     4 
     5 theory Enum
     6 imports Map
     7 begin
     8 
     9 subsection {* Class @{text enum} *}
    10 
    11 class enum =
    12   fixes enum :: "'a list"
    13   fixes enum_all :: "('a \<Rightarrow> bool) \<Rightarrow> bool"
    14   fixes enum_ex :: "('a \<Rightarrow> bool) \<Rightarrow> bool"
    15   assumes UNIV_enum: "UNIV = set enum"
    16     and enum_distinct: "distinct enum"
    17   assumes enum_all_UNIV: "enum_all P \<longleftrightarrow> Ball UNIV P"
    18   assumes enum_ex_UNIV: "enum_ex P \<longleftrightarrow> Bex UNIV P" 
    19    -- {* tailored towards simple instantiation *}
    20 begin
    21 
    22 subclass finite proof
    23 qed (simp add: UNIV_enum)
    24 
    25 lemma enum_UNIV:
    26   "set enum = UNIV"
    27   by (simp only: UNIV_enum)
    28 
    29 lemma in_enum: "x \<in> set enum"
    30   by (simp add: enum_UNIV)
    31 
    32 lemma enum_eq_I:
    33   assumes "\<And>x. x \<in> set xs"
    34   shows "set enum = set xs"
    35 proof -
    36   from assms UNIV_eq_I have "UNIV = set xs" by auto
    37   with enum_UNIV show ?thesis by simp
    38 qed
    39 
    40 lemma card_UNIV_length_enum:
    41   "card (UNIV :: 'a set) = length enum"
    42   by (simp add: UNIV_enum distinct_card enum_distinct)
    43 
    44 lemma enum_all [simp]:
    45   "enum_all = HOL.All"
    46   by (simp add: fun_eq_iff enum_all_UNIV)
    47 
    48 lemma enum_ex [simp]:
    49   "enum_ex = HOL.Ex" 
    50   by (simp add: fun_eq_iff enum_ex_UNIV)
    51 
    52 end
    53 
    54 
    55 subsection {* Implementations using @{class enum} *}
    56 
    57 subsubsection {* Unbounded operations and quantifiers *}
    58 
    59 lemma Collect_code [code]:
    60   "Collect P = set (filter P enum)"
    61   by (simp add: enum_UNIV)
    62 
    63 lemma vimage_code [code]:
    64   "f -` B = set (filter (%x. f x : B) enum_class.enum)"
    65   unfolding vimage_def Collect_code ..
    66 
    67 definition card_UNIV :: "'a itself \<Rightarrow> nat"
    68 where
    69   [code del]: "card_UNIV TYPE('a) = card (UNIV :: 'a set)"
    70 
    71 lemma [code]:
    72   "card_UNIV TYPE('a :: enum) = card (set (Enum.enum :: 'a list))"
    73   by (simp only: card_UNIV_def enum_UNIV)
    74 
    75 lemma all_code [code]: "(\<forall>x. P x) \<longleftrightarrow> enum_all P"
    76   by simp
    77 
    78 lemma exists_code [code]: "(\<exists>x. P x) \<longleftrightarrow> enum_ex P"
    79   by simp
    80 
    81 lemma exists1_code [code]: "(\<exists>!x. P x) \<longleftrightarrow> list_ex1 P enum"
    82   by (auto simp add: list_ex1_iff enum_UNIV)
    83 
    84 
    85 subsubsection {* An executable choice operator *}
    86 
    87 definition
    88   [code del]: "enum_the = The"
    89 
    90 lemma [code]:
    91   "The P = (case filter P enum of [x] => x | _ => enum_the P)"
    92 proof -
    93   {
    94     fix a
    95     assume filter_enum: "filter P enum = [a]"
    96     have "The P = a"
    97     proof (rule the_equality)
    98       fix x
    99       assume "P x"
   100       show "x = a"
   101       proof (rule ccontr)
   102         assume "x \<noteq> a"
   103         from filter_enum obtain us vs
   104           where enum_eq: "enum = us @ [a] @ vs"
   105           and "\<forall> x \<in> set us. \<not> P x"
   106           and "\<forall> x \<in> set vs. \<not> P x"
   107           and "P a"
   108           by (auto simp add: filter_eq_Cons_iff) (simp only: filter_empty_conv[symmetric])
   109         with `P x` in_enum[of x, unfolded enum_eq] `x \<noteq> a` show "False" by auto
   110       qed
   111     next
   112       from filter_enum show "P a" by (auto simp add: filter_eq_Cons_iff)
   113     qed
   114   }
   115   from this show ?thesis
   116     unfolding enum_the_def by (auto split: list.split)
   117 qed
   118 
   119 declare [[code abort: enum_the]]
   120 
   121 code_printing
   122   constant enum_the \<rightharpoonup> (Eval) "(fn '_ => raise Match)"
   123 
   124 
   125 subsubsection {* Equality and order on functions *}
   126 
   127 instantiation "fun" :: (enum, equal) equal
   128 begin
   129 
   130 definition
   131   "HOL.equal f g \<longleftrightarrow> (\<forall>x \<in> set enum. f x = g x)"
   132 
   133 instance proof
   134 qed (simp_all add: equal_fun_def fun_eq_iff enum_UNIV)
   135 
   136 end
   137 
   138 lemma [code]:
   139   "HOL.equal f g \<longleftrightarrow> enum_all (%x. f x = g x)"
   140   by (auto simp add: equal fun_eq_iff)
   141 
   142 lemma [code nbe]:
   143   "HOL.equal (f :: _ \<Rightarrow> _) f \<longleftrightarrow> True"
   144   by (fact equal_refl)
   145 
   146 lemma order_fun [code]:
   147   fixes f g :: "'a\<Colon>enum \<Rightarrow> 'b\<Colon>order"
   148   shows "f \<le> g \<longleftrightarrow> enum_all (\<lambda>x. f x \<le> g x)"
   149     and "f < g \<longleftrightarrow> f \<le> g \<and> enum_ex (\<lambda>x. f x \<noteq> g x)"
   150   by (simp_all add: fun_eq_iff le_fun_def order_less_le)
   151 
   152 
   153 subsubsection {* Operations on relations *}
   154 
   155 lemma [code]:
   156   "Id = image (\<lambda>x. (x, x)) (set Enum.enum)"
   157   by (auto intro: imageI in_enum)
   158 
   159 lemma tranclp_unfold [code]:
   160   "tranclp r a b \<longleftrightarrow> (a, b) \<in> trancl {(x, y). r x y}"
   161   by (simp add: trancl_def)
   162 
   163 lemma rtranclp_rtrancl_eq [code]:
   164   "rtranclp r x y \<longleftrightarrow> (x, y) \<in> rtrancl {(x, y). r x y}"
   165   by (simp add: rtrancl_def)
   166 
   167 lemma max_ext_eq [code]:
   168   "max_ext R = {(X, Y). finite X \<and> finite Y \<and> Y \<noteq> {} \<and> (\<forall>x. x \<in> X \<longrightarrow> (\<exists>xa \<in> Y. (x, xa) \<in> R))}"
   169   by (auto simp add: max_ext.simps)
   170 
   171 lemma max_extp_eq [code]:
   172   "max_extp r x y \<longleftrightarrow> (x, y) \<in> max_ext {(x, y). r x y}"
   173   by (simp add: max_ext_def)
   174 
   175 lemma mlex_eq [code]:
   176   "f <*mlex*> R = {(x, y). f x < f y \<or> (f x \<le> f y \<and> (x, y) \<in> R)}"
   177   by (auto simp add: mlex_prod_def)
   178 
   179 
   180 subsubsection {* Bounded accessible part *}
   181 
   182 primrec bacc :: "('a \<times> 'a) set \<Rightarrow> nat \<Rightarrow> 'a set" 
   183 where
   184   "bacc r 0 = {x. \<forall> y. (y, x) \<notin> r}"
   185 | "bacc r (Suc n) = (bacc r n \<union> {x. \<forall>y. (y, x) \<in> r \<longrightarrow> y \<in> bacc r n})"
   186 
   187 lemma bacc_subseteq_acc:
   188   "bacc r n \<subseteq> Wellfounded.acc r"
   189   by (induct n) (auto intro: acc.intros)
   190 
   191 lemma bacc_mono:
   192   "n \<le> m \<Longrightarrow> bacc r n \<subseteq> bacc r m"
   193   by (induct rule: dec_induct) auto
   194   
   195 lemma bacc_upper_bound:
   196   "bacc (r :: ('a \<times> 'a) set)  (card (UNIV :: 'a::finite set)) = (\<Union>n. bacc r n)"
   197 proof -
   198   have "mono (bacc r)" unfolding mono_def by (simp add: bacc_mono)
   199   moreover have "\<forall>n. bacc r n = bacc r (Suc n) \<longrightarrow> bacc r (Suc n) = bacc r (Suc (Suc n))" by auto
   200   moreover have "finite (range (bacc r))" by auto
   201   ultimately show ?thesis
   202    by (intro finite_mono_strict_prefix_implies_finite_fixpoint)
   203      (auto intro: finite_mono_remains_stable_implies_strict_prefix)
   204 qed
   205 
   206 lemma acc_subseteq_bacc:
   207   assumes "finite r"
   208   shows "Wellfounded.acc r \<subseteq> (\<Union>n. bacc r n)"
   209 proof
   210   fix x
   211   assume "x : Wellfounded.acc r"
   212   then have "\<exists> n. x : bacc r n"
   213   proof (induct x arbitrary: rule: acc.induct)
   214     case (accI x)
   215     then have "\<forall>y. \<exists> n. (y, x) \<in> r --> y : bacc r n" by simp
   216     from choice[OF this] obtain n where n: "\<forall>y. (y, x) \<in> r \<longrightarrow> y \<in> bacc r (n y)" ..
   217     obtain n where "\<And>y. (y, x) : r \<Longrightarrow> y : bacc r n"
   218     proof
   219       fix y assume y: "(y, x) : r"
   220       with n have "y : bacc r (n y)" by auto
   221       moreover have "n y <= Max ((%(y, x). n y) ` r)"
   222         using y `finite r` by (auto intro!: Max_ge)
   223       note bacc_mono[OF this, of r]
   224       ultimately show "y : bacc r (Max ((%(y, x). n y) ` r))" by auto
   225     qed
   226     then show ?case
   227       by (auto simp add: Let_def intro!: exI[of _ "Suc n"])
   228   qed
   229   then show "x : (UN n. bacc r n)" by auto
   230 qed
   231 
   232 lemma acc_bacc_eq:
   233   fixes A :: "('a :: finite \<times> 'a) set"
   234   assumes "finite A"
   235   shows "Wellfounded.acc A = bacc A (card (UNIV :: 'a set))"
   236   using assms by (metis acc_subseteq_bacc bacc_subseteq_acc bacc_upper_bound order_eq_iff)
   237 
   238 lemma [code]:
   239   fixes xs :: "('a::finite \<times> 'a) list"
   240   shows "Wellfounded.acc (set xs) = bacc (set xs) (card_UNIV TYPE('a))"
   241   by (simp add: card_UNIV_def acc_bacc_eq)
   242 
   243 
   244 subsection {* Default instances for @{class enum} *}
   245 
   246 lemma map_of_zip_enum_is_Some:
   247   assumes "length ys = length (enum \<Colon> 'a\<Colon>enum list)"
   248   shows "\<exists>y. map_of (zip (enum \<Colon> 'a\<Colon>enum list) ys) x = Some y"
   249 proof -
   250   from assms have "x \<in> set (enum \<Colon> 'a\<Colon>enum list) \<longleftrightarrow>
   251     (\<exists>y. map_of (zip (enum \<Colon> 'a\<Colon>enum list) ys) x = Some y)"
   252     by (auto intro!: map_of_zip_is_Some)
   253   then show ?thesis using enum_UNIV by auto
   254 qed
   255 
   256 lemma map_of_zip_enum_inject:
   257   fixes xs ys :: "'b\<Colon>enum list"
   258   assumes length: "length xs = length (enum \<Colon> 'a\<Colon>enum list)"
   259       "length ys = length (enum \<Colon> 'a\<Colon>enum list)"
   260     and map_of: "the \<circ> map_of (zip (enum \<Colon> 'a\<Colon>enum list) xs) = the \<circ> map_of (zip (enum \<Colon> 'a\<Colon>enum list) ys)"
   261   shows "xs = ys"
   262 proof -
   263   have "map_of (zip (enum \<Colon> 'a list) xs) = map_of (zip (enum \<Colon> 'a list) ys)"
   264   proof
   265     fix x :: 'a
   266     from length map_of_zip_enum_is_Some obtain y1 y2
   267       where "map_of (zip (enum \<Colon> 'a list) xs) x = Some y1"
   268         and "map_of (zip (enum \<Colon> 'a list) ys) x = Some y2" by blast
   269     moreover from map_of
   270       have "the (map_of (zip (enum \<Colon> 'a\<Colon>enum list) xs) x) = the (map_of (zip (enum \<Colon> 'a\<Colon>enum list) ys) x)"
   271       by (auto dest: fun_cong)
   272     ultimately show "map_of (zip (enum \<Colon> 'a\<Colon>enum list) xs) x = map_of (zip (enum \<Colon> 'a\<Colon>enum list) ys) x"
   273       by simp
   274   qed
   275   with length enum_distinct show "xs = ys" by (rule map_of_zip_inject)
   276 qed
   277 
   278 definition all_n_lists :: "(('a :: enum) list \<Rightarrow> bool) \<Rightarrow> nat \<Rightarrow> bool"
   279 where
   280   "all_n_lists P n \<longleftrightarrow> (\<forall>xs \<in> set (List.n_lists n enum). P xs)"
   281 
   282 lemma [code]:
   283   "all_n_lists P n \<longleftrightarrow> (if n = 0 then P [] else enum_all (%x. all_n_lists (%xs. P (x # xs)) (n - 1)))"
   284   unfolding all_n_lists_def enum_all
   285   by (cases n) (auto simp add: enum_UNIV)
   286 
   287 definition ex_n_lists :: "(('a :: enum) list \<Rightarrow> bool) \<Rightarrow> nat \<Rightarrow> bool"
   288 where
   289   "ex_n_lists P n \<longleftrightarrow> (\<exists>xs \<in> set (List.n_lists n enum). P xs)"
   290 
   291 lemma [code]:
   292   "ex_n_lists P n \<longleftrightarrow> (if n = 0 then P [] else enum_ex (%x. ex_n_lists (%xs. P (x # xs)) (n - 1)))"
   293   unfolding ex_n_lists_def enum_ex
   294   by (cases n) (auto simp add: enum_UNIV)
   295 
   296 instantiation "fun" :: (enum, enum) enum
   297 begin
   298 
   299 definition
   300   "enum = map (\<lambda>ys. the o map_of (zip (enum\<Colon>'a list) ys)) (List.n_lists (length (enum\<Colon>'a\<Colon>enum list)) enum)"
   301 
   302 definition
   303   "enum_all P = all_n_lists (\<lambda>bs. P (the o map_of (zip enum bs))) (length (enum :: 'a list))"
   304 
   305 definition
   306   "enum_ex P = ex_n_lists (\<lambda>bs. P (the o map_of (zip enum bs))) (length (enum :: 'a list))"
   307 
   308 instance proof
   309   show "UNIV = set (enum \<Colon> ('a \<Rightarrow> 'b) list)"
   310   proof (rule UNIV_eq_I)
   311     fix f :: "'a \<Rightarrow> 'b"
   312     have "f = the \<circ> map_of (zip (enum \<Colon> 'a\<Colon>enum list) (map f enum))"
   313       by (auto simp add: map_of_zip_map fun_eq_iff intro: in_enum)
   314     then show "f \<in> set enum"
   315       by (auto simp add: enum_fun_def set_n_lists intro: in_enum)
   316   qed
   317 next
   318   from map_of_zip_enum_inject
   319   show "distinct (enum \<Colon> ('a \<Rightarrow> 'b) list)"
   320     by (auto intro!: inj_onI simp add: enum_fun_def
   321       distinct_map distinct_n_lists enum_distinct set_n_lists)
   322 next
   323   fix P
   324   show "enum_all (P :: ('a \<Rightarrow> 'b) \<Rightarrow> bool) = Ball UNIV P"
   325   proof
   326     assume "enum_all P"
   327     show "Ball UNIV P"
   328     proof
   329       fix f :: "'a \<Rightarrow> 'b"
   330       have f: "f = the \<circ> map_of (zip (enum \<Colon> 'a\<Colon>enum list) (map f enum))"
   331         by (auto simp add: map_of_zip_map fun_eq_iff intro: in_enum)
   332       from `enum_all P` have "P (the \<circ> map_of (zip enum (map f enum)))"
   333         unfolding enum_all_fun_def all_n_lists_def
   334         apply (simp add: set_n_lists)
   335         apply (erule_tac x="map f enum" in allE)
   336         apply (auto intro!: in_enum)
   337         done
   338       from this f show "P f" by auto
   339     qed
   340   next
   341     assume "Ball UNIV P"
   342     from this show "enum_all P"
   343       unfolding enum_all_fun_def all_n_lists_def by auto
   344   qed
   345 next
   346   fix P
   347   show "enum_ex (P :: ('a \<Rightarrow> 'b) \<Rightarrow> bool) = Bex UNIV P"
   348   proof
   349     assume "enum_ex P"
   350     from this show "Bex UNIV P"
   351       unfolding enum_ex_fun_def ex_n_lists_def by auto
   352   next
   353     assume "Bex UNIV P"
   354     from this obtain f where "P f" ..
   355     have f: "f = the \<circ> map_of (zip (enum \<Colon> 'a\<Colon>enum list) (map f enum))"
   356       by (auto simp add: map_of_zip_map fun_eq_iff intro: in_enum) 
   357     from `P f` this have "P (the \<circ> map_of (zip (enum \<Colon> 'a\<Colon>enum list) (map f enum)))"
   358       by auto
   359     from  this show "enum_ex P"
   360       unfolding enum_ex_fun_def ex_n_lists_def
   361       apply (auto simp add: set_n_lists)
   362       apply (rule_tac x="map f enum" in exI)
   363       apply (auto intro!: in_enum)
   364       done
   365   qed
   366 qed
   367 
   368 end
   369 
   370 lemma enum_fun_code [code]: "enum = (let enum_a = (enum \<Colon> 'a\<Colon>{enum, equal} list)
   371   in map (\<lambda>ys. the o map_of (zip enum_a ys)) (List.n_lists (length enum_a) enum))"
   372   by (simp add: enum_fun_def Let_def)
   373 
   374 lemma enum_all_fun_code [code]:
   375   "enum_all P = (let enum_a = (enum :: 'a::{enum, equal} list)
   376    in all_n_lists (\<lambda>bs. P (the o map_of (zip enum_a bs))) (length enum_a))"
   377   by (simp only: enum_all_fun_def Let_def)
   378 
   379 lemma enum_ex_fun_code [code]:
   380   "enum_ex P = (let enum_a = (enum :: 'a::{enum, equal} list)
   381    in ex_n_lists (\<lambda>bs. P (the o map_of (zip enum_a bs))) (length enum_a))"
   382   by (simp only: enum_ex_fun_def Let_def)
   383 
   384 instantiation set :: (enum) enum
   385 begin
   386 
   387 definition
   388   "enum = map set (sublists enum)"
   389 
   390 definition
   391   "enum_all P \<longleftrightarrow> (\<forall>A\<in>set enum. P (A::'a set))"
   392 
   393 definition
   394   "enum_ex P \<longleftrightarrow> (\<exists>A\<in>set enum. P (A::'a set))"
   395 
   396 instance proof
   397 qed (simp_all add: enum_set_def enum_all_set_def enum_ex_set_def sublists_powset distinct_set_sublists
   398   enum_distinct enum_UNIV)
   399 
   400 end
   401 
   402 instantiation unit :: enum
   403 begin
   404 
   405 definition
   406   "enum = [()]"
   407 
   408 definition
   409   "enum_all P = P ()"
   410 
   411 definition
   412   "enum_ex P = P ()"
   413 
   414 instance proof
   415 qed (auto simp add: enum_unit_def enum_all_unit_def enum_ex_unit_def)
   416 
   417 end
   418 
   419 instantiation bool :: enum
   420 begin
   421 
   422 definition
   423   "enum = [False, True]"
   424 
   425 definition
   426   "enum_all P \<longleftrightarrow> P False \<and> P True"
   427 
   428 definition
   429   "enum_ex P \<longleftrightarrow> P False \<or> P True"
   430 
   431 instance proof
   432 qed (simp_all only: enum_bool_def enum_all_bool_def enum_ex_bool_def UNIV_bool, simp_all)
   433 
   434 end
   435 
   436 instantiation prod :: (enum, enum) enum
   437 begin
   438 
   439 definition
   440   "enum = List.product enum enum"
   441 
   442 definition
   443   "enum_all P = enum_all (%x. enum_all (%y. P (x, y)))"
   444 
   445 definition
   446   "enum_ex P = enum_ex (%x. enum_ex (%y. P (x, y)))"
   447 
   448  
   449 instance by default
   450   (simp_all add: enum_prod_def distinct_product
   451     enum_UNIV enum_distinct enum_all_prod_def enum_ex_prod_def)
   452 
   453 end
   454 
   455 instantiation sum :: (enum, enum) enum
   456 begin
   457 
   458 definition
   459   "enum = map Inl enum @ map Inr enum"
   460 
   461 definition
   462   "enum_all P \<longleftrightarrow> enum_all (\<lambda>x. P (Inl x)) \<and> enum_all (\<lambda>x. P (Inr x))"
   463 
   464 definition
   465   "enum_ex P \<longleftrightarrow> enum_ex (\<lambda>x. P (Inl x)) \<or> enum_ex (\<lambda>x. P (Inr x))"
   466 
   467 instance proof
   468 qed (simp_all only: enum_sum_def enum_all_sum_def enum_ex_sum_def UNIV_sum,
   469   auto simp add: enum_UNIV distinct_map enum_distinct)
   470 
   471 end
   472 
   473 instantiation option :: (enum) enum
   474 begin
   475 
   476 definition
   477   "enum = None # map Some enum"
   478 
   479 definition
   480   "enum_all P \<longleftrightarrow> P None \<and> enum_all (\<lambda>x. P (Some x))"
   481 
   482 definition
   483   "enum_ex P \<longleftrightarrow> P None \<or> enum_ex (\<lambda>x. P (Some x))"
   484 
   485 instance proof
   486 qed (simp_all only: enum_option_def enum_all_option_def enum_ex_option_def UNIV_option_conv,
   487   auto simp add: distinct_map enum_UNIV enum_distinct)
   488 
   489 end
   490 
   491 
   492 subsection {* Small finite types *}
   493 
   494 text {* We define small finite types for the use in Quickcheck *}
   495 
   496 datatype finite_1 = a\<^sub>1
   497 
   498 notation (output) a\<^sub>1  ("a\<^sub>1")
   499 
   500 lemma UNIV_finite_1:
   501   "UNIV = {a\<^sub>1}"
   502   by (auto intro: finite_1.exhaust)
   503 
   504 instantiation finite_1 :: enum
   505 begin
   506 
   507 definition
   508   "enum = [a\<^sub>1]"
   509 
   510 definition
   511   "enum_all P = P a\<^sub>1"
   512 
   513 definition
   514   "enum_ex P = P a\<^sub>1"
   515 
   516 instance proof
   517 qed (simp_all only: enum_finite_1_def enum_all_finite_1_def enum_ex_finite_1_def UNIV_finite_1, simp_all)
   518 
   519 end
   520 
   521 instantiation finite_1 :: linorder
   522 begin
   523 
   524 definition less_finite_1 :: "finite_1 \<Rightarrow> finite_1 \<Rightarrow> bool"
   525 where
   526   "x < (y :: finite_1) \<longleftrightarrow> False"
   527 
   528 definition less_eq_finite_1 :: "finite_1 \<Rightarrow> finite_1 \<Rightarrow> bool"
   529 where
   530   "x \<le> (y :: finite_1) \<longleftrightarrow> True"
   531 
   532 instance
   533 apply (intro_classes)
   534 apply (auto simp add: less_finite_1_def less_eq_finite_1_def)
   535 apply (metis finite_1.exhaust)
   536 done
   537 
   538 end
   539 
   540 hide_const (open) a\<^sub>1
   541 
   542 datatype finite_2 = a\<^sub>1 | a\<^sub>2
   543 
   544 notation (output) a\<^sub>1  ("a\<^sub>1")
   545 notation (output) a\<^sub>2  ("a\<^sub>2")
   546 
   547 lemma UNIV_finite_2:
   548   "UNIV = {a\<^sub>1, a\<^sub>2}"
   549   by (auto intro: finite_2.exhaust)
   550 
   551 instantiation finite_2 :: enum
   552 begin
   553 
   554 definition
   555   "enum = [a\<^sub>1, a\<^sub>2]"
   556 
   557 definition
   558   "enum_all P \<longleftrightarrow> P a\<^sub>1 \<and> P a\<^sub>2"
   559 
   560 definition
   561   "enum_ex P \<longleftrightarrow> P a\<^sub>1 \<or> P a\<^sub>2"
   562 
   563 instance proof
   564 qed (simp_all only: enum_finite_2_def enum_all_finite_2_def enum_ex_finite_2_def UNIV_finite_2, simp_all)
   565 
   566 end
   567 
   568 instantiation finite_2 :: linorder
   569 begin
   570 
   571 definition less_finite_2 :: "finite_2 \<Rightarrow> finite_2 \<Rightarrow> bool"
   572 where
   573   "x < y \<longleftrightarrow> x = a\<^sub>1 \<and> y = a\<^sub>2"
   574 
   575 definition less_eq_finite_2 :: "finite_2 \<Rightarrow> finite_2 \<Rightarrow> bool"
   576 where
   577   "x \<le> y \<longleftrightarrow> x = y \<or> x < (y :: finite_2)"
   578 
   579 instance
   580 apply (intro_classes)
   581 apply (auto simp add: less_finite_2_def less_eq_finite_2_def)
   582 apply (metis finite_2.nchotomy)+
   583 done
   584 
   585 end
   586 
   587 hide_const (open) a\<^sub>1 a\<^sub>2
   588 
   589 datatype finite_3 = a\<^sub>1 | a\<^sub>2 | a\<^sub>3
   590 
   591 notation (output) a\<^sub>1  ("a\<^sub>1")
   592 notation (output) a\<^sub>2  ("a\<^sub>2")
   593 notation (output) a\<^sub>3  ("a\<^sub>3")
   594 
   595 lemma UNIV_finite_3:
   596   "UNIV = {a\<^sub>1, a\<^sub>2, a\<^sub>3}"
   597   by (auto intro: finite_3.exhaust)
   598 
   599 instantiation finite_3 :: enum
   600 begin
   601 
   602 definition
   603   "enum = [a\<^sub>1, a\<^sub>2, a\<^sub>3]"
   604 
   605 definition
   606   "enum_all P \<longleftrightarrow> P a\<^sub>1 \<and> P a\<^sub>2 \<and> P a\<^sub>3"
   607 
   608 definition
   609   "enum_ex P \<longleftrightarrow> P a\<^sub>1 \<or> P a\<^sub>2 \<or> P a\<^sub>3"
   610 
   611 instance proof
   612 qed (simp_all only: enum_finite_3_def enum_all_finite_3_def enum_ex_finite_3_def UNIV_finite_3, simp_all)
   613 
   614 end
   615 
   616 instantiation finite_3 :: linorder
   617 begin
   618 
   619 definition less_finite_3 :: "finite_3 \<Rightarrow> finite_3 \<Rightarrow> bool"
   620 where
   621   "x < y = (case x of a\<^sub>1 \<Rightarrow> y \<noteq> a\<^sub>1 | a\<^sub>2 \<Rightarrow> y = a\<^sub>3 | a\<^sub>3 \<Rightarrow> False)"
   622 
   623 definition less_eq_finite_3 :: "finite_3 \<Rightarrow> finite_3 \<Rightarrow> bool"
   624 where
   625   "x \<le> y \<longleftrightarrow> x = y \<or> x < (y :: finite_3)"
   626 
   627 instance proof (intro_classes)
   628 qed (auto simp add: less_finite_3_def less_eq_finite_3_def split: finite_3.split_asm)
   629 
   630 end
   631 
   632 hide_const (open) a\<^sub>1 a\<^sub>2 a\<^sub>3
   633 
   634 datatype finite_4 = a\<^sub>1 | a\<^sub>2 | a\<^sub>3 | a\<^sub>4
   635 
   636 notation (output) a\<^sub>1  ("a\<^sub>1")
   637 notation (output) a\<^sub>2  ("a\<^sub>2")
   638 notation (output) a\<^sub>3  ("a\<^sub>3")
   639 notation (output) a\<^sub>4  ("a\<^sub>4")
   640 
   641 lemma UNIV_finite_4:
   642   "UNIV = {a\<^sub>1, a\<^sub>2, a\<^sub>3, a\<^sub>4}"
   643   by (auto intro: finite_4.exhaust)
   644 
   645 instantiation finite_4 :: enum
   646 begin
   647 
   648 definition
   649   "enum = [a\<^sub>1, a\<^sub>2, a\<^sub>3, a\<^sub>4]"
   650 
   651 definition
   652   "enum_all P \<longleftrightarrow> P a\<^sub>1 \<and> P a\<^sub>2 \<and> P a\<^sub>3 \<and> P a\<^sub>4"
   653 
   654 definition
   655   "enum_ex P \<longleftrightarrow> P a\<^sub>1 \<or> P a\<^sub>2 \<or> P a\<^sub>3 \<or> P a\<^sub>4"
   656 
   657 instance proof
   658 qed (simp_all only: enum_finite_4_def enum_all_finite_4_def enum_ex_finite_4_def UNIV_finite_4, simp_all)
   659 
   660 end
   661 
   662 hide_const (open) a\<^sub>1 a\<^sub>2 a\<^sub>3 a\<^sub>4
   663 
   664 
   665 datatype finite_5 = a\<^sub>1 | a\<^sub>2 | a\<^sub>3 | a\<^sub>4 | a\<^sub>5
   666 
   667 notation (output) a\<^sub>1  ("a\<^sub>1")
   668 notation (output) a\<^sub>2  ("a\<^sub>2")
   669 notation (output) a\<^sub>3  ("a\<^sub>3")
   670 notation (output) a\<^sub>4  ("a\<^sub>4")
   671 notation (output) a\<^sub>5  ("a\<^sub>5")
   672 
   673 lemma UNIV_finite_5:
   674   "UNIV = {a\<^sub>1, a\<^sub>2, a\<^sub>3, a\<^sub>4, a\<^sub>5}"
   675   by (auto intro: finite_5.exhaust)
   676 
   677 instantiation finite_5 :: enum
   678 begin
   679 
   680 definition
   681   "enum = [a\<^sub>1, a\<^sub>2, a\<^sub>3, a\<^sub>4, a\<^sub>5]"
   682 
   683 definition
   684   "enum_all P \<longleftrightarrow> P a\<^sub>1 \<and> P a\<^sub>2 \<and> P a\<^sub>3 \<and> P a\<^sub>4 \<and> P a\<^sub>5"
   685 
   686 definition
   687   "enum_ex P \<longleftrightarrow> P a\<^sub>1 \<or> P a\<^sub>2 \<or> P a\<^sub>3 \<or> P a\<^sub>4 \<or> P a\<^sub>5"
   688 
   689 instance proof
   690 qed (simp_all only: enum_finite_5_def enum_all_finite_5_def enum_ex_finite_5_def UNIV_finite_5, simp_all)
   691 
   692 end
   693 
   694 hide_const (open) a\<^sub>1 a\<^sub>2 a\<^sub>3 a\<^sub>4 a\<^sub>5
   695 
   696 
   697 subsection {* Closing up *}
   698 
   699 hide_type (open) finite_1 finite_2 finite_3 finite_4 finite_5
   700 hide_const (open) enum enum_all enum_ex all_n_lists ex_n_lists ntrancl
   701 
   702 end