Nominal/Abs.thy
changeset 1440 ffd5540ac2e9
child 1442 097b25706436
child 1449 b66d754bf1c2
equal deleted inserted replaced
1439:bdd73f8bb63b 1440:ffd5540ac2e9
       
     1 theory Abs
       
     2 imports "Nominal2_Atoms" "Nominal2_Eqvt" "Nominal2_Supp" "../Quotient" "../Quotient_Product"
       
     3 begin
       
     4 
       
     5 (* the next three lemmas that should be in Nominal \<dots>\<dots>must be cleaned *)
       
     6 
       
     7 
       
     8 fun
       
     9   alpha_gen 
       
    10 where
       
    11   alpha_gen[simp del]:
       
    12   "alpha_gen (bs, x) R f pi (cs, y) \<longleftrightarrow> 
       
    13      f x - bs = f y - cs \<and> (f x - bs) \<sharp>* pi \<and> R (pi \<bullet> x) y \<and> pi \<bullet> bs = cs"
       
    14 
       
    15 notation
       
    16   alpha_gen ("_ \<approx>gen _ _ _ _" [100, 100, 100, 100, 100] 100)
       
    17 
       
    18 lemma [mono]: "R1 \<le> R2 \<Longrightarrow> alpha_gen x R1 \<le> alpha_gen x R2"
       
    19   by (cases x) (auto simp add: le_fun_def le_bool_def alpha_gen.simps)
       
    20 
       
    21 lemma alpha_gen_refl:
       
    22   assumes a: "R x x"
       
    23   shows "(bs, x) \<approx>gen R f 0 (bs, x)"
       
    24   using a by (simp add: alpha_gen fresh_star_def fresh_zero_perm)
       
    25 
       
    26 lemma alpha_gen_sym:
       
    27   assumes a: "(bs, x) \<approx>gen R f p (cs, y)"
       
    28   and     b: "R (p \<bullet> x) y \<Longrightarrow> R (- p \<bullet> y) x"
       
    29   shows "(cs, y) \<approx>gen R f (- p) (bs, x)"
       
    30   using a b 
       
    31   by (auto simp add: alpha_gen fresh_star_def fresh_def supp_minus_perm)
       
    32 
       
    33 lemma alpha_gen_trans:
       
    34   assumes a: "(bs, x) \<approx>gen R f p1 (cs, y)"
       
    35   and     b: "(cs, y) \<approx>gen R f p2 (ds, z)"
       
    36   and     c: "\<lbrakk>R (p1 \<bullet> x) y; R (p2 \<bullet> y) z\<rbrakk> \<Longrightarrow> R ((p2 + p1) \<bullet> x) z"
       
    37   shows "(bs, x) \<approx>gen R f (p2 + p1) (ds, z)"
       
    38   using a b c 
       
    39   using supp_plus_perm
       
    40   apply(simp add: alpha_gen fresh_star_def fresh_def)
       
    41   apply(blast)
       
    42   done
       
    43 
       
    44 lemma alpha_gen_eqvt:
       
    45   assumes a: "(bs, x) \<approx>gen R f q (cs, y)"
       
    46   and     b: "R (q \<bullet> x) y \<Longrightarrow> R (p \<bullet> (q \<bullet> x)) (p \<bullet> y)"
       
    47   and     c: "p \<bullet> (f x) = f (p \<bullet> x)"
       
    48   and     d: "p \<bullet> (f y) = f (p \<bullet> y)"
       
    49   shows "(p \<bullet> bs, p \<bullet> x) \<approx>gen R f (p \<bullet> q) (p \<bullet> cs, p \<bullet> y)"
       
    50   using a b
       
    51   apply(simp add: alpha_gen c[symmetric] d[symmetric] Diff_eqvt[symmetric])
       
    52   apply(simp add: permute_eqvt[symmetric])
       
    53   apply(simp add: fresh_star_permute_iff)
       
    54   apply(clarsimp)
       
    55   done
       
    56 
       
    57 lemma alpha_gen_compose_sym:
       
    58   fixes pi
       
    59   assumes b: "(aa, t) \<approx>gen (\<lambda>x1 x2. R x1 x2 \<and> R x2 x1) f pi (ab, s)"
       
    60   and a: "\<And>pi t s. (R t s \<Longrightarrow> R (pi \<bullet> t) (pi \<bullet> s))"
       
    61   shows "(ab, s) \<approx>gen R f (- pi) (aa, t)"
       
    62   using b apply -
       
    63   apply(simp add: alpha_gen.simps)
       
    64   apply(erule conjE)+
       
    65   apply(rule conjI)
       
    66   apply(simp add: fresh_star_def fresh_minus_perm)
       
    67   apply(subgoal_tac "R (- pi \<bullet> s) ((- pi) \<bullet> (pi \<bullet> t))")
       
    68   apply simp
       
    69   apply(clarify)
       
    70   apply(simp)
       
    71   apply(rule a)
       
    72   apply assumption
       
    73   done
       
    74 
       
    75 lemma alpha_gen_compose_trans:
       
    76   fixes pi pia
       
    77   assumes b: "(aa, t) \<approx>gen (\<lambda>x1 x2. R x1 x2 \<and> (\<forall>x. R x2 x \<longrightarrow> R x1 x)) f pi (ab, ta)"
       
    78   and c: "(ab, ta) \<approx>gen R f pia (ac, sa)"
       
    79   and a: "\<And>pi t s. (R t s \<Longrightarrow> R (pi \<bullet> t) (pi \<bullet> s))"
       
    80   shows "(aa, t) \<approx>gen R f (pia + pi) (ac, sa)"
       
    81   using b c apply -
       
    82   apply(simp add: alpha_gen.simps)
       
    83   apply(erule conjE)+
       
    84   apply(simp add: fresh_star_plus)
       
    85   apply(drule_tac x="- pia \<bullet> sa" in spec)
       
    86   apply(drule mp)
       
    87   apply(rotate_tac 5)
       
    88   apply(drule_tac pi="- pia" in a)
       
    89   apply(simp)
       
    90   apply(rotate_tac 7)
       
    91   apply(drule_tac pi="pia" in a)
       
    92   apply(simp)
       
    93   done
       
    94 
       
    95 lemma alpha_gen_compose_eqvt:
       
    96   fixes  pia
       
    97   assumes b: "(g d, t) \<approx>gen (\<lambda>x1 x2. R x1 x2 \<and> R (pi \<bullet> x1) (pi \<bullet> x2)) f pia (g e, s)"
       
    98   and     c: "\<And>y. pi \<bullet> (g y) = g (pi \<bullet> y)"
       
    99   and     a: "\<And>x. pi \<bullet> (f x) = f (pi \<bullet> x)"
       
   100   shows  "(g (pi \<bullet> d), pi \<bullet> t) \<approx>gen R f (pi \<bullet> pia) (g (pi \<bullet> e), pi \<bullet> s)"
       
   101   using b
       
   102   apply -
       
   103   apply(simp add: alpha_gen.simps)
       
   104   apply(erule conjE)+
       
   105   apply(rule conjI)
       
   106   apply(rule_tac ?p1="- pi" in permute_eq_iff[THEN iffD1])
       
   107   apply(simp add: a[symmetric] atom_eqvt Diff_eqvt insert_eqvt set_eqvt empty_eqvt c[symmetric])
       
   108   apply(rule conjI)
       
   109   apply(rule_tac ?p1="- pi" in fresh_star_permute_iff[THEN iffD1])
       
   110   apply(simp add: a[symmetric] atom_eqvt Diff_eqvt insert_eqvt set_eqvt empty_eqvt c[symmetric])
       
   111   apply(subst permute_eqvt[symmetric])
       
   112   apply(simp)
       
   113   oops
       
   114 
       
   115 fun
       
   116   alpha_abs 
       
   117 where
       
   118   "alpha_abs (bs, x) (cs, y) = (\<exists>p. (bs, x) \<approx>gen (op=) supp p (cs, y))"
       
   119 
       
   120 notation
       
   121   alpha_abs ("_ \<approx>abs _")
       
   122 
       
   123 lemma alpha_abs_swap:
       
   124   assumes a1: "a \<notin> (supp x) - bs"
       
   125   and     a2: "b \<notin> (supp x) - bs"
       
   126   shows "(bs, x) \<approx>abs ((a \<rightleftharpoons> b) \<bullet> bs, (a \<rightleftharpoons> b) \<bullet> x)"
       
   127   apply(simp)
       
   128   apply(rule_tac x="(a \<rightleftharpoons> b)" in exI)
       
   129   unfolding alpha_gen
       
   130   apply(simp)
       
   131   apply(simp add: supp_eqvt[symmetric] Diff_eqvt[symmetric])
       
   132   apply(simp add: swap_set_not_in[OF a1 a2])
       
   133   apply(subgoal_tac "supp (a \<rightleftharpoons> b) \<subseteq> {a, b}")
       
   134   using a1 a2
       
   135   apply(simp add: fresh_star_def fresh_def)
       
   136   apply(blast)
       
   137   apply(simp add: supp_swap)
       
   138   done
       
   139 
       
   140 lemma alpha_gen_swap_fun:
       
   141   assumes f_eqvt: "\<And>pi. (pi \<bullet> (f x)) = f (pi \<bullet> x)"
       
   142   assumes a1: "a \<notin> (f x) - bs"
       
   143   and     a2: "b \<notin> (f x) - bs"
       
   144   shows "\<exists>pi. (bs, x) \<approx>gen (op=) f pi ((a \<rightleftharpoons> b) \<bullet> bs, (a \<rightleftharpoons> b) \<bullet> x)"
       
   145   apply(rule_tac x="(a \<rightleftharpoons> b)" in exI)
       
   146   apply(simp add: alpha_gen)
       
   147   apply(simp add: f_eqvt[symmetric] Diff_eqvt[symmetric])
       
   148   apply(simp add: swap_set_not_in[OF a1 a2])
       
   149   apply(subgoal_tac "supp (a \<rightleftharpoons> b) \<subseteq> {a, b}")
       
   150   using a1 a2
       
   151   apply(simp add: fresh_star_def fresh_def)
       
   152   apply(blast)
       
   153   apply(simp add: supp_swap)
       
   154   done
       
   155 
       
   156 fun
       
   157   supp_abs_fun
       
   158 where
       
   159   "supp_abs_fun (bs, x) = (supp x) - bs"
       
   160 
       
   161 lemma supp_abs_fun_lemma:
       
   162   assumes a: "x \<approx>abs y" 
       
   163   shows "supp_abs_fun x = supp_abs_fun y"
       
   164   using a
       
   165   apply(induct rule: alpha_abs.induct)
       
   166   apply(simp add: alpha_gen)
       
   167   done
       
   168   
       
   169 quotient_type 'a abs = "(atom set \<times> 'a::pt)" / "alpha_abs"
       
   170   apply(rule equivpI)
       
   171   unfolding reflp_def symp_def transp_def
       
   172   apply(simp_all)
       
   173   (* refl *)
       
   174   apply(clarify)
       
   175   apply(rule exI)
       
   176   apply(rule alpha_gen_refl)
       
   177   apply(simp)
       
   178   (* symm *)
       
   179   apply(clarify)
       
   180   apply(rule exI)
       
   181   apply(rule alpha_gen_sym)
       
   182   apply(assumption)
       
   183   apply(clarsimp)
       
   184   (* trans *)
       
   185   apply(clarify)
       
   186   apply(rule exI)
       
   187   apply(rule alpha_gen_trans)
       
   188   apply(assumption)
       
   189   apply(assumption)
       
   190   apply(simp)
       
   191   done
       
   192 
       
   193 quotient_definition
       
   194   "Abs::atom set \<Rightarrow> ('a::pt) \<Rightarrow> 'a abs"
       
   195 is
       
   196   "Pair::atom set \<Rightarrow> ('a::pt) \<Rightarrow> (atom set \<times> 'a)"
       
   197 
       
   198 lemma [quot_respect]:
       
   199   shows "((op =) ===> (op =) ===> alpha_abs) Pair Pair"
       
   200   apply(clarsimp)
       
   201   apply(rule exI)
       
   202   apply(rule alpha_gen_refl)
       
   203   apply(simp)
       
   204   done
       
   205 
       
   206 lemma [quot_respect]:
       
   207   shows "((op =) ===> alpha_abs ===> alpha_abs) permute permute"
       
   208   apply(clarsimp)
       
   209   apply(rule exI)
       
   210   apply(rule alpha_gen_eqvt)
       
   211   apply(assumption)
       
   212   apply(simp_all add: supp_eqvt)
       
   213   done
       
   214 
       
   215 lemma [quot_respect]:
       
   216   shows "(alpha_abs ===> (op =)) supp_abs_fun supp_abs_fun"
       
   217   apply(simp add: supp_abs_fun_lemma)
       
   218   done
       
   219 
       
   220 lemma abs_induct:
       
   221   "\<lbrakk>\<And>as (x::'a::pt). P (Abs as x)\<rbrakk> \<Longrightarrow> P t"
       
   222   apply(lifting prod.induct[where 'a="atom set" and 'b="'a"])
       
   223   done
       
   224 
       
   225 (* TEST case *)
       
   226 lemmas abs_induct2 = prod.induct[where 'a="atom set" and 'b="'a::pt", quot_lifted]
       
   227 thm abs_induct abs_induct2
       
   228 
       
   229 instantiation abs :: (pt) pt
       
   230 begin
       
   231 
       
   232 quotient_definition
       
   233   "permute_abs::perm \<Rightarrow> ('a::pt abs) \<Rightarrow> 'a abs"
       
   234 is
       
   235   "permute:: perm \<Rightarrow> (atom set \<times> 'a::pt) \<Rightarrow> (atom set \<times> 'a::pt)"
       
   236 
       
   237 lemma permute_ABS [simp]:
       
   238   fixes x::"'a::pt"  (* ??? has to be 'a \<dots> 'b does not work *)
       
   239   shows "(p \<bullet> (Abs as x)) = Abs (p \<bullet> as) (p \<bullet> x)"
       
   240   by (lifting permute_prod.simps(1)[where 'a="atom set" and 'b="'a"])
       
   241 
       
   242 instance
       
   243   apply(default)
       
   244   apply(induct_tac [!] x rule: abs_induct)
       
   245   apply(simp_all)
       
   246   done
       
   247 
       
   248 end
       
   249 
       
   250 quotient_definition
       
   251   "supp_Abs_fun :: ('a::pt) abs \<Rightarrow> atom \<Rightarrow> bool"
       
   252 is
       
   253   "supp_abs_fun"
       
   254 
       
   255 lemma supp_Abs_fun_simp:
       
   256   shows "supp_Abs_fun (Abs bs x) = (supp x) - bs"
       
   257   by (lifting supp_abs_fun.simps(1))
       
   258 
       
   259 lemma supp_Abs_fun_eqvt [eqvt]:
       
   260   shows "(p \<bullet> supp_Abs_fun x) = supp_Abs_fun (p \<bullet> x)"
       
   261   apply(induct_tac x rule: abs_induct)
       
   262   apply(simp add: supp_Abs_fun_simp supp_eqvt Diff_eqvt)
       
   263   done
       
   264 
       
   265 lemma supp_Abs_fun_fresh:
       
   266   shows "a \<sharp> Abs bs x \<Longrightarrow> a \<sharp> supp_Abs_fun (Abs bs x)"
       
   267   apply(rule fresh_fun_eqvt_app)
       
   268   apply(simp add: eqvts_raw)
       
   269   apply(simp)
       
   270   done
       
   271 
       
   272 lemma Abs_swap:
       
   273   assumes a1: "a \<notin> (supp x) - bs"
       
   274   and     a2: "b \<notin> (supp x) - bs"
       
   275   shows "(Abs bs x) = (Abs ((a \<rightleftharpoons> b) \<bullet> bs) ((a \<rightleftharpoons> b) \<bullet> x))"
       
   276   using a1 a2 by (lifting alpha_abs_swap)
       
   277 
       
   278 lemma Abs_supports:
       
   279   shows "((supp x) - as) supports (Abs as x)"
       
   280   unfolding supports_def
       
   281   apply(clarify)
       
   282   apply(simp (no_asm))
       
   283   apply(subst Abs_swap[symmetric])
       
   284   apply(simp_all)
       
   285   done
       
   286 
       
   287 lemma supp_Abs_subset1:
       
   288   fixes x::"'a::fs"
       
   289   shows "(supp x) - as \<subseteq> supp (Abs as x)"
       
   290   apply(simp add: supp_conv_fresh)
       
   291   apply(auto)
       
   292   apply(drule_tac supp_Abs_fun_fresh)
       
   293   apply(simp only: supp_Abs_fun_simp)
       
   294   apply(simp add: fresh_def)
       
   295   apply(simp add: supp_finite_atom_set finite_supp)
       
   296   done
       
   297 
       
   298 lemma supp_Abs_subset2:
       
   299   fixes x::"'a::fs"
       
   300   shows "supp (Abs as x) \<subseteq> (supp x) - as"
       
   301   apply(rule supp_is_subset)
       
   302   apply(rule Abs_supports)
       
   303   apply(simp add: finite_supp)
       
   304   done
       
   305 
       
   306 lemma supp_Abs:
       
   307   fixes x::"'a::fs"
       
   308   shows "supp (Abs as x) = (supp x) - as"
       
   309   apply(rule_tac subset_antisym)
       
   310   apply(rule supp_Abs_subset2)
       
   311   apply(rule supp_Abs_subset1)
       
   312   done
       
   313 
       
   314 instance abs :: (fs) fs
       
   315   apply(default)
       
   316   apply(induct_tac x rule: abs_induct)
       
   317   apply(simp add: supp_Abs)
       
   318   apply(simp add: finite_supp)
       
   319   done
       
   320 
       
   321 lemma Abs_fresh_iff:
       
   322   fixes x::"'a::fs"
       
   323   shows "a \<sharp> Abs bs x \<longleftrightarrow> a \<in> bs \<or> (a \<notin> bs \<and> a \<sharp> x)"
       
   324   apply(simp add: fresh_def)
       
   325   apply(simp add: supp_Abs)
       
   326   apply(auto)
       
   327   done
       
   328 
       
   329 lemma Abs_eq_iff:
       
   330   shows "Abs bs x = Abs cs y \<longleftrightarrow> (\<exists>p. (bs, x) \<approx>gen (op =) supp p (cs, y))"
       
   331   by (lifting alpha_abs.simps(1))
       
   332 
       
   333 
       
   334 
       
   335 (* 
       
   336   below is a construction site for showing that in the
       
   337   single-binder case, the old and new alpha equivalence 
       
   338   coincide
       
   339 *)
       
   340 
       
   341 fun
       
   342   alpha1
       
   343 where
       
   344   "alpha1 (a, x) (b, y) \<longleftrightarrow> (a = b \<and> x = y) \<or> (a \<noteq> b \<and> x = (a \<rightleftharpoons> b) \<bullet> y \<and> a \<sharp> y)"
       
   345 
       
   346 notation 
       
   347   alpha1 ("_ \<approx>abs1 _")
       
   348 
       
   349 fun
       
   350   alpha2
       
   351 where
       
   352   "alpha2 (a, x) (b, y) \<longleftrightarrow> (\<exists>c. c \<sharp> (a,b,x,y) \<and> ((c \<rightleftharpoons> a) \<bullet> x) = ((c \<rightleftharpoons> b) \<bullet> y))"
       
   353 
       
   354 notation 
       
   355   alpha2 ("_ \<approx>abs2 _")
       
   356 
       
   357 
       
   358 lemma
       
   359   assumes a: "(a, x) \<approx>abs1 (b, y)" "sort_of a = sort_of b"
       
   360   shows "({a}, x) \<approx>abs ({b}, y)"
       
   361 using a
       
   362 apply(simp)
       
   363 apply(erule disjE)
       
   364 apply(simp)
       
   365 apply(rule exI)
       
   366 apply(rule alpha_gen_refl)
       
   367 apply(simp)
       
   368 apply(rule_tac x="(a \<rightleftharpoons> b)" in  exI)
       
   369 apply(simp add: alpha_gen)
       
   370 apply(simp add: fresh_def)
       
   371 apply(rule conjI)
       
   372 apply(rule_tac ?p1="(a \<rightleftharpoons> b)" in  permute_eq_iff[THEN iffD1])
       
   373 apply(rule trans)
       
   374 apply(simp add: Diff_eqvt supp_eqvt)
       
   375 apply(subst swap_set_not_in)
       
   376 back
       
   377 apply(simp)
       
   378 apply(simp)
       
   379 apply(simp add: permute_set_eq)
       
   380 apply(simp add: eqvts)
       
   381 apply(rule_tac ?p1="(a \<rightleftharpoons> b)" in fresh_star_permute_iff[THEN iffD1])
       
   382 apply(simp add: permute_self)
       
   383 apply(simp add: Diff_eqvt supp_eqvt)
       
   384 apply(simp add: permute_set_eq)
       
   385 apply(subgoal_tac "supp (a \<rightleftharpoons> b) \<subseteq> {a, b}")
       
   386 apply(simp add: fresh_star_def fresh_def)
       
   387 apply(blast)
       
   388 apply(simp add: supp_swap)
       
   389 done
       
   390 
       
   391 lemma perm_zero:
       
   392   assumes a: "\<forall>x::atom. p \<bullet> x = x"
       
   393   shows "p = 0"
       
   394 using a
       
   395 by (simp add: expand_perm_eq)
       
   396 
       
   397 fun
       
   398   add_perm 
       
   399 where
       
   400   "add_perm [] = 0"
       
   401 | "add_perm ((a, b) # xs) = (a \<rightleftharpoons> b) + add_perm xs"
       
   402 
       
   403 fun
       
   404   elem_perm
       
   405 where
       
   406   "elem_perm [] = {}"
       
   407 | "elem_perm ((a, b) # xs) = {a, b} \<union> elem_perm xs"
       
   408 
       
   409 
       
   410 lemma add_perm_apend:
       
   411   shows "add_perm (xs @ ys) = add_perm xs + add_perm ys"
       
   412 apply(induct xs arbitrary: ys)
       
   413 apply(auto simp add: add_assoc)
       
   414 done
       
   415 
       
   416 lemma perm_list_exists:
       
   417   fixes p::perm
       
   418   shows "\<exists>xs. p = add_perm xs \<and> supp xs \<subseteq> supp p"
       
   419 apply(induct p taking: "\<lambda>p::perm. card (supp p)" rule: measure_induct)
       
   420 apply(rename_tac p)
       
   421 apply(case_tac "supp p = {}")
       
   422 apply(simp)
       
   423 apply(simp add: supp_perm)
       
   424 apply(drule perm_zero)
       
   425 apply(simp)
       
   426 apply(rule_tac x="[]" in exI)
       
   427 apply(simp add: supp_Nil)
       
   428 apply(subgoal_tac "\<exists>x. x \<in> supp p")
       
   429 defer
       
   430 apply(auto)[1]
       
   431 apply(erule exE)
       
   432 apply(drule_tac x="p + (((- p) \<bullet> x) \<rightleftharpoons> x)" in spec)
       
   433 apply(drule mp)
       
   434 defer
       
   435 apply(erule exE)
       
   436 apply(rule_tac x="xs @ [((- p) \<bullet> x, x)]" in exI)
       
   437 apply(simp add: add_perm_apend)
       
   438 apply(erule conjE)
       
   439 apply(drule sym)
       
   440 apply(simp)
       
   441 apply(simp add: expand_perm_eq)
       
   442 apply(simp add: supp_append)
       
   443 apply(simp add: supp_perm supp_Cons supp_Nil supp_Pair supp_atom)
       
   444 apply(rule conjI)
       
   445 prefer 2
       
   446 apply(auto)[1]
       
   447 apply (metis left_minus minus_unique permute_atom_def_raw permute_minus_cancel(2))
       
   448 defer
       
   449 apply(rule psubset_card_mono)
       
   450 apply(simp add: finite_supp)
       
   451 apply(rule psubsetI)
       
   452 defer
       
   453 apply(subgoal_tac "x \<notin> supp (p + (- p \<bullet> x \<rightleftharpoons> x))")
       
   454 apply(blast)
       
   455 apply(simp add: supp_perm)
       
   456 defer
       
   457 apply(auto simp add: supp_perm)[1]
       
   458 apply(case_tac "x = xa")
       
   459 apply(simp)
       
   460 apply(case_tac "((- p) \<bullet> x) = xa")
       
   461 apply(simp)
       
   462 apply(case_tac "sort_of xa = sort_of x")
       
   463 apply(simp)
       
   464 apply(auto)[1]
       
   465 apply(simp)
       
   466 apply(simp)
       
   467 apply(subgoal_tac "{a. p \<bullet> (- p \<bullet> x \<rightleftharpoons> x) \<bullet> a \<noteq> a} \<subseteq> {a. p \<bullet> a \<noteq> a}")
       
   468 apply(blast)
       
   469 apply(auto simp add: supp_perm)[1]
       
   470 apply(case_tac "x = xa")
       
   471 apply(simp)
       
   472 apply(case_tac "((- p) \<bullet> x) = xa")
       
   473 apply(simp)
       
   474 apply(case_tac "sort_of xa = sort_of x")
       
   475 apply(simp)
       
   476 apply(auto)[1]
       
   477 apply(simp)
       
   478 apply(simp)
       
   479 done
       
   480 
       
   481 lemma tt0:
       
   482   fixes p::perm
       
   483   shows "(supp x) \<sharp>* p \<Longrightarrow> \<forall>a \<in> supp p. a \<sharp> x"
       
   484 apply(auto simp add: fresh_star_def supp_perm fresh_def)
       
   485 done
       
   486 
       
   487 lemma uu0:
       
   488   shows "(\<forall>a \<in> elem_perm xs. a \<sharp> x) \<Longrightarrow> (add_perm xs \<bullet> x) = x"
       
   489 apply(induct xs rule: add_perm.induct)
       
   490 apply(simp)
       
   491 apply(simp add: swap_fresh_fresh)
       
   492 done
       
   493 
       
   494 lemma yy0:
       
   495   fixes xs::"(atom \<times> atom) list"
       
   496   shows "supp xs = elem_perm xs"
       
   497 apply(induct xs rule: elem_perm.induct)
       
   498 apply(auto simp add: supp_Nil supp_Cons supp_Pair supp_atom)
       
   499 done
       
   500 
       
   501 lemma tt1:
       
   502   shows "(supp x) \<sharp>* p \<Longrightarrow> p \<bullet> x = x"
       
   503 apply(drule tt0)
       
   504 apply(subgoal_tac "\<exists>xs. p = add_perm xs \<and> supp xs \<subseteq> supp p")
       
   505 prefer 2
       
   506 apply(rule perm_list_exists)
       
   507 apply(erule exE)
       
   508 apply(simp only: yy0)
       
   509 apply(rule uu0)
       
   510 apply(auto)
       
   511 done
       
   512 
       
   513 
       
   514 lemma perm_induct_test:
       
   515   fixes P :: "perm => bool"
       
   516   assumes fin: "finite (supp p)" 
       
   517   assumes zero: "P 0"
       
   518   assumes swap: "\<And>a b. \<lbrakk>sort_of a = sort_of b; a \<noteq> b\<rbrakk> \<Longrightarrow> P (a \<rightleftharpoons> b)"
       
   519   assumes plus: "\<And>p1 p2. \<lbrakk>supp p1 \<inter> supp p2 = {}; P p1; P p2\<rbrakk> \<Longrightarrow> P (p1 + p2)"
       
   520   shows "P p"
       
   521 using fin
       
   522 apply(induct F\<equiv>"supp p" arbitrary: p rule: finite_induct)
       
   523 apply(simp add: supp_perm)
       
   524 apply(drule perm_zero)
       
   525 apply(simp add: zero)
       
   526 apply(rotate_tac 3)
       
   527 oops
       
   528 
       
   529 lemma yy:
       
   530   assumes "S1 - {x} = S2 - {x}" "x \<in> S1" "x \<in> S2"
       
   531   shows "S1 = S2"
       
   532 using assms
       
   533 apply (metis insert_Diff_single insert_absorb)
       
   534 done
       
   535 
       
   536 lemma permute_boolI:
       
   537   fixes P::"bool"
       
   538   shows "p \<bullet> P \<Longrightarrow> P"
       
   539 apply(simp add: permute_bool_def)
       
   540 done
       
   541 
       
   542 lemma permute_boolE:
       
   543   fixes P::"bool"
       
   544   shows "P \<Longrightarrow> p \<bullet> P"
       
   545 apply(simp add: permute_bool_def)
       
   546 done
       
   547 
       
   548 lemma kk:
       
   549   assumes a: "p \<bullet> x = y"
       
   550   shows "\<forall>a \<in> supp x. (p \<bullet> a) \<in> supp y"
       
   551 using a
       
   552 apply(auto)
       
   553 apply(rule_tac p="- p" in permute_boolI)
       
   554 apply(simp add: mem_eqvt supp_eqvt)
       
   555 done
       
   556 
       
   557 lemma ww:
       
   558   assumes "a \<notin> supp x" "b \<in> supp x" "a \<noteq> b" "sort_of a = sort_of b"
       
   559   shows "((a \<rightleftharpoons> b) \<bullet> x) \<noteq> x"
       
   560 apply(subgoal_tac "(supp x) supports x")
       
   561 apply(simp add: supports_def)
       
   562 using assms
       
   563 apply -
       
   564 apply(drule_tac x="a" in spec)
       
   565 defer
       
   566 apply(rule supp_supports)
       
   567 apply(auto)
       
   568 apply(rotate_tac 1)
       
   569 apply(drule_tac p="(a \<rightleftharpoons> b)" in permute_boolE)
       
   570 apply(simp add: mem_eqvt supp_eqvt)
       
   571 done
       
   572 
       
   573 lemma alpha_abs_sym:
       
   574   assumes a: "({a}, x) \<approx>abs ({b}, y)"
       
   575   shows "({b}, y) \<approx>abs ({a}, x)"
       
   576 using a
       
   577 apply(simp)
       
   578 apply(erule exE)
       
   579 apply(rule_tac x="- p" in exI)
       
   580 apply(simp add: alpha_gen)
       
   581 apply(simp add: fresh_star_def fresh_minus_perm)
       
   582 apply (metis permute_minus_cancel(2))
       
   583 done
       
   584 
       
   585 lemma alpha_abs_trans:
       
   586   assumes a: "({a1}, x1) \<approx>abs ({a2}, x2)"
       
   587   assumes b: "({a2}, x2) \<approx>abs ({a3}, x3)"
       
   588   shows "({a1}, x1) \<approx>abs ({a3}, x3)"
       
   589 using a b
       
   590 apply(simp)
       
   591 apply(erule exE)+
       
   592 apply(rule_tac x="pa + p" in exI)
       
   593 apply(simp add: alpha_gen)
       
   594 apply(simp add: fresh_star_def fresh_plus_perm)
       
   595 done
       
   596 
       
   597 lemma alpha_equal:
       
   598   assumes a: "({a}, x) \<approx>abs ({a}, y)" 
       
   599   shows "(a, x) \<approx>abs1 (a, y)"
       
   600 using a
       
   601 apply(simp)
       
   602 apply(erule exE)
       
   603 apply(simp add: alpha_gen)
       
   604 apply(erule conjE)+
       
   605 apply(case_tac "a \<notin> supp x")
       
   606 apply(simp)
       
   607 apply(subgoal_tac "supp x \<sharp>* p")
       
   608 apply(drule tt1)
       
   609 apply(simp)
       
   610 apply(simp)
       
   611 apply(simp)
       
   612 apply(case_tac "a \<notin> supp y")
       
   613 apply(simp)
       
   614 apply(drule tt1)
       
   615 apply(clarify)
       
   616 apply(simp (no_asm_use))
       
   617 apply(simp)
       
   618 apply(simp)
       
   619 apply(drule yy)
       
   620 apply(simp)
       
   621 apply(simp)
       
   622 apply(simp)
       
   623 apply(case_tac "a \<sharp> p")
       
   624 apply(subgoal_tac "supp y \<sharp>* p")
       
   625 apply(drule tt1)
       
   626 apply(clarify)
       
   627 apply(simp (no_asm_use))
       
   628 apply(metis)
       
   629 apply(auto simp add: fresh_star_def)[1]
       
   630 apply(frule_tac kk)
       
   631 apply(drule_tac x="a" in bspec)
       
   632 apply(simp)
       
   633 apply(simp add: fresh_def)
       
   634 apply(simp add: supp_perm)
       
   635 apply(subgoal_tac "((p \<bullet> a) \<sharp> p)")
       
   636 apply(simp add: fresh_def supp_perm)
       
   637 apply(simp add: fresh_star_def)
       
   638 done
       
   639 
       
   640 lemma alpha_unequal:
       
   641   assumes a: "({a}, x) \<approx>abs ({b}, y)" "sort_of a = sort_of b" "a \<noteq> b"
       
   642   shows "(a, x) \<approx>abs1 (b, y)"
       
   643 using a
       
   644 apply -
       
   645 apply(subgoal_tac "a \<notin> supp x - {a}")
       
   646 apply(subgoal_tac "b \<notin> supp x - {a}")
       
   647 defer
       
   648 apply(simp add: alpha_gen)
       
   649 apply(simp)
       
   650 apply(drule_tac alpha_abs_swap)
       
   651 apply(assumption)
       
   652 apply(simp only: insert_eqvt empty_eqvt swap_atom_simps)
       
   653 apply(drule alpha_abs_sym)
       
   654 apply(rotate_tac 4)
       
   655 apply(drule_tac alpha_abs_trans)
       
   656 apply(assumption)
       
   657 apply(drule alpha_equal)
       
   658 apply(simp)
       
   659 apply(rule_tac p="(a \<rightleftharpoons> b)" in permute_boolI)
       
   660 apply(simp add: fresh_eqvt)
       
   661 apply(simp add: fresh_def)
       
   662 done
       
   663 
       
   664 lemma alpha_new_old:
       
   665   assumes a: "({a}, x) \<approx>abs ({b}, y)" "sort_of a = sort_of b" 
       
   666   shows "(a, x) \<approx>abs1 (b, y)"
       
   667 using a
       
   668 apply(case_tac "a=b")
       
   669 apply(simp only: alpha_equal)
       
   670 apply(drule alpha_unequal)
       
   671 apply(simp)
       
   672 apply(simp)
       
   673 apply(simp)
       
   674 done
       
   675 
       
   676 fun
       
   677   distinct_perms 
       
   678 where
       
   679   "distinct_perms [] = True"
       
   680 | "distinct_perms (p # ps) = (supp p \<inter> supp ps = {} \<and> distinct_perms ps)"
       
   681 
       
   682 (* support of concrete atom sets *)
       
   683 
       
   684 lemma atom_eqvt_raw:
       
   685   fixes p::"perm"
       
   686   shows "(p \<bullet> atom) = atom"
       
   687 by (simp add: expand_fun_eq permute_fun_def atom_eqvt)
       
   688 
       
   689 lemma atom_image_cong:
       
   690   shows "(atom ` X = atom ` Y) = (X = Y)"
       
   691 apply(rule inj_image_eq_iff)
       
   692 apply(simp add: inj_on_def)
       
   693 done
       
   694 
       
   695 lemma supp_atom_image:
       
   696   fixes as::"'a::at_base set"
       
   697   shows "supp (atom ` as) = supp as"
       
   698 apply(simp add: supp_def)
       
   699 apply(simp add: image_eqvt)
       
   700 apply(simp add: atom_eqvt_raw)
       
   701 apply(simp add: atom_image_cong)
       
   702 done
       
   703 
       
   704 lemma swap_atom_image_fresh: "\<lbrakk>a \<sharp> atom ` (fn :: ('a :: at_base set)); b \<sharp> atom ` fn\<rbrakk> \<Longrightarrow> (a \<rightleftharpoons> b) \<bullet> fn = fn"
       
   705   apply (simp add: fresh_def)
       
   706   apply (simp add: supp_atom_image)
       
   707   apply (fold fresh_def)
       
   708   apply (simp add: swap_fresh_fresh)
       
   709   done
       
   710 
       
   711 
       
   712 end
       
   713