Nominal/Ex/ExLet.thy
changeset 1773 c0eac04ae3b4
parent 1765 9a894c42e80e
child 1774 c34347ec7ab3
equal deleted inserted replaced
1772:48c2eb84d5ce 1773:c0eac04ae3b4
       
     1 theory ExLet
       
     2 imports "../Parser" "../../Attic/Prove"
       
     3 begin
       
     4 
       
     5 text {* example 3 or example 5 from Terms.thy *}
       
     6 
       
     7 atom_decl name
       
     8 
       
     9 ML {* val _ = recursive := false *}
       
    10 ML {* val _ = alpha_type := AlphaLst *}
       
    11 nominal_datatype trm =
       
    12   Vr "name"
       
    13 | Ap "trm" "trm"
       
    14 | Lm x::"name" t::"trm"  bind x in t
       
    15 | Lt a::"lts" t::"trm"   bind "bn a" in t
       
    16 (*| L a::"lts" t1::"trm" t2::"trm"  bind "bn a" in t1, bind "bn a" in t2*)
       
    17 and lts =
       
    18   Lnil
       
    19 | Lcons "name" "trm" "lts"
       
    20 binder
       
    21   bn
       
    22 where
       
    23   "bn Lnil = []"
       
    24 | "bn (Lcons x t l) = (atom x) # (bn l)"
       
    25 
       
    26 
       
    27 thm alpha_trm_raw_alpha_lts_raw_alpha_bn_raw.intros
       
    28 
       
    29 thm trm_lts.fv
       
    30 thm trm_lts.eq_iff
       
    31 thm trm_lts.bn
       
    32 thm trm_lts.perm
       
    33 thm trm_lts.induct[no_vars]
       
    34 thm trm_lts.inducts[no_vars]
       
    35 thm trm_lts.distinct
       
    36 (*thm trm_lts.supp*)
       
    37 thm trm_lts.fv[simplified trm_lts.supp(1-2)]
       
    38 
       
    39 
       
    40 primrec
       
    41   permute_bn_raw
       
    42 where
       
    43   "permute_bn_raw pi (Lnil_raw) = Lnil_raw"
       
    44 | "permute_bn_raw pi (Lcons_raw a t l) = Lcons_raw (pi \<bullet> a) t (permute_bn_raw pi l)"
       
    45 
       
    46 quotient_definition
       
    47   "permute_bn :: perm \<Rightarrow> lts \<Rightarrow> lts"
       
    48 is
       
    49   "permute_bn_raw"
       
    50 
       
    51 lemma [quot_respect]: "((op =) ===> alpha_lts_raw ===> alpha_lts_raw) permute_bn_raw permute_bn_raw"
       
    52   apply simp
       
    53   apply clarify
       
    54   apply (erule alpha_trm_raw_alpha_lts_raw_alpha_bn_raw.inducts)
       
    55   apply simp_all
       
    56   apply (rule alpha_trm_raw_alpha_lts_raw_alpha_bn_raw.intros)
       
    57   apply simp
       
    58   apply (rule alpha_trm_raw_alpha_lts_raw_alpha_bn_raw.intros)
       
    59   apply simp
       
    60   done
       
    61 
       
    62 lemmas permute_bn = permute_bn_raw.simps[quot_lifted]
       
    63 
       
    64 lemma permute_bn_zero:
       
    65   "permute_bn 0 a = a"
       
    66   apply(induct a rule: trm_lts.inducts(2))
       
    67   apply(rule TrueI)
       
    68   apply(simp_all add:permute_bn eqvts)
       
    69   done
       
    70 
       
    71 lemma permute_bn_add:
       
    72   "permute_bn (p + q) a = permute_bn p (permute_bn q a)"
       
    73   oops
       
    74 
       
    75 lemma permute_bn_alpha_bn: "alpha_bn lts (permute_bn q lts)"
       
    76   apply(induct lts rule: trm_lts.inducts(2))
       
    77   apply(rule TrueI)
       
    78   apply(simp_all add:permute_bn eqvts trm_lts.eq_iff)
       
    79   done
       
    80 
       
    81 lemma perm_bn:
       
    82   "p \<bullet> bn l = bn(permute_bn p l)"
       
    83   apply(induct l rule: trm_lts.inducts(2))
       
    84   apply(rule TrueI)
       
    85   apply(simp_all add:permute_bn eqvts)
       
    86   done
       
    87 
       
    88 lemma fv_perm_bn:
       
    89   "fv_bn l = fv_bn (permute_bn p l)"
       
    90   apply(induct l rule: trm_lts.inducts(2))
       
    91   apply(rule TrueI)
       
    92   apply(simp_all add:permute_bn eqvts)
       
    93   done
       
    94 
       
    95 lemma fv_fv_bn:
       
    96   "fv_bn l - set (bn l) = fv_lts l - set (bn l)"
       
    97   apply(induct l rule: trm_lts.inducts(2))
       
    98   apply(rule TrueI)
       
    99   apply(simp_all add:permute_bn eqvts)
       
   100   by blast
       
   101 
       
   102 lemma Lt_subst:
       
   103   "supp (Abs_lst (bn lts) trm) \<sharp>* q \<Longrightarrow> (Lt lts trm) = Lt (permute_bn q lts) (q \<bullet> trm)"
       
   104   apply (simp only: trm_lts.eq_iff)
       
   105   apply (rule_tac x="q" in exI)
       
   106   apply (simp add: alphas)
       
   107   apply (simp add: permute_bn_alpha_bn)
       
   108   apply (simp add: perm_bn[symmetric])
       
   109   apply (simp add: eqvts[symmetric])
       
   110   apply (simp add: supp_abs)
       
   111   apply (simp add: trm_lts.supp)
       
   112   apply (rule supp_perm_eq[symmetric])
       
   113   apply (subst supp_finite_atom_set)
       
   114   apply (rule finite_Diff)
       
   115   apply (simp add: finite_supp)
       
   116   apply (assumption)
       
   117   done
       
   118 
       
   119 
       
   120 lemma fin_bn:
       
   121   "finite (set (bn l))"
       
   122   apply(induct l rule: trm_lts.inducts(2))
       
   123   apply(simp_all add:permute_bn eqvts)
       
   124   done
       
   125 
       
   126 thm trm_lts.inducts[no_vars]
       
   127 
       
   128 lemma 
       
   129   fixes t::trm
       
   130   and   l::lts
       
   131   and   c::"'a::fs"
       
   132   assumes a1: "\<And>name c. P1 c (Vr name)"
       
   133   and     a2: "\<And>trm1 trm2 c. \<lbrakk>\<And>d. P1 d trm1; \<And>d. P1 d trm2\<rbrakk> \<Longrightarrow> P1 c (Ap trm1 trm2)"
       
   134   and     a3: "\<And>name trm c. \<lbrakk>atom name \<sharp> c; \<And>d. P1 d trm\<rbrakk> \<Longrightarrow> P1 c (Lm name trm)"
       
   135   and     a4: "\<And>lts trm c. \<lbrakk>set (bn lts) \<sharp>* c; \<And>d. P2 d lts; \<And>d. P1 d trm\<rbrakk> \<Longrightarrow> P1 c (Lt lts trm)"
       
   136   and     a5: "\<And>c. P2 c Lnil"
       
   137   and     a6: "\<And>name trm lts c. \<lbrakk>\<And>d. P1 d trm; \<And>d. P2 d lts\<rbrakk> \<Longrightarrow> P2 c (Lcons name trm lts)"
       
   138   shows "P1 c t" and "P2 c l"
       
   139 proof -
       
   140   have "(\<And>(p::perm) (c::'a::fs). P1 c (p \<bullet> t))" and
       
   141        b': "(\<And>(p::perm) (q::perm) (c::'a::fs). P2 c (permute_bn p (q \<bullet> l)))"
       
   142     apply(induct rule: trm_lts.inducts)
       
   143     apply(simp)
       
   144     apply(rule a1)
       
   145     apply(simp)
       
   146     apply(rule a2)
       
   147     apply(simp)
       
   148     apply(simp)
       
   149     apply(simp)
       
   150     apply(subgoal_tac "\<exists>q. (q \<bullet> (atom (p \<bullet> name))) \<sharp> c \<and> supp (Lm (p \<bullet> name) (p \<bullet> trm)) \<sharp>* q")
       
   151     apply(erule exE)
       
   152     apply(rule_tac t="Lm (p \<bullet> name) (p \<bullet> trm)" 
       
   153                and s="q\<bullet> Lm (p \<bullet> name) (p \<bullet> trm)" in subst)
       
   154     apply(rule supp_perm_eq)
       
   155     apply(simp)
       
   156     apply(simp)
       
   157     apply(rule a3)
       
   158     apply(simp add: atom_eqvt)
       
   159     apply(subst permute_plus[symmetric])
       
   160     apply(blast)
       
   161     apply(rule at_set_avoiding2_atom)
       
   162     apply(simp add: finite_supp)
       
   163     apply(simp add: finite_supp)
       
   164     apply(simp add: fresh_def)
       
   165     apply(simp add: trm_lts.fv[simplified trm_lts.supp])
       
   166     apply(simp)
       
   167     apply(subgoal_tac "\<exists>q. (q \<bullet> set (bn (p \<bullet> lts))) \<sharp>* c \<and> supp (Abs_lst (bn (p \<bullet> lts)) (p \<bullet> trm)) \<sharp>* q")
       
   168     apply(erule exE)
       
   169     apply(erule conjE)
       
   170     apply(subst Lt_subst)
       
   171     apply assumption
       
   172     apply(rule a4)
       
   173     apply(simp add:perm_bn[symmetric])
       
   174     apply(simp add: eqvts)
       
   175     apply (simp add: fresh_star_def fresh_def)
       
   176     apply(rotate_tac 1)
       
   177     apply(drule_tac x="q + p" in meta_spec)
       
   178     apply(simp)
       
   179     apply(rule at_set_avoiding2)
       
   180     apply(rule fin_bn)
       
   181     apply(simp add: finite_supp)
       
   182     apply(simp add: finite_supp)
       
   183     apply(simp add: fresh_star_def fresh_def supp_abs)
       
   184     apply(simp add: eqvts permute_bn)
       
   185     apply(rule a5)
       
   186     apply(simp add: permute_bn)
       
   187     apply(rule a6)
       
   188     apply simp
       
   189     apply simp
       
   190     done
       
   191   then have a: "P1 c (0 \<bullet> t)" by blast
       
   192   have "P2 c (permute_bn 0 (0 \<bullet> l))" using b' by blast
       
   193   then show "P1 c t" and "P2 c l" using a permute_bn_zero by simp_all
       
   194 qed
       
   195 
       
   196 
       
   197 
       
   198 lemma lets_bla:
       
   199   "x \<noteq> z \<Longrightarrow> y \<noteq> z \<Longrightarrow> x \<noteq> y \<Longrightarrow>(Lt (Lcons x (Vr y) Lnil) (Vr x)) \<noteq> (Lt (Lcons x (Vr z) Lnil) (Vr x))"
       
   200   by (simp add: trm_lts.eq_iff)
       
   201 
       
   202 lemma lets_ok:
       
   203   "(Lt (Lcons x (Vr y) Lnil) (Vr x)) = (Lt (Lcons y (Vr y) Lnil) (Vr y))"
       
   204   apply (simp add: trm_lts.eq_iff)
       
   205   apply (rule_tac x="(x \<leftrightarrow> y)" in exI)
       
   206   apply (simp_all add: alphas)
       
   207   apply (simp add: fresh_star_def eqvts)
       
   208   done
       
   209 
       
   210 lemma lets_ok3:
       
   211   "x \<noteq> y \<Longrightarrow>
       
   212    (Lt (Lcons x (Ap (Vr y) (Vr x)) (Lcons y (Vr y) Lnil)) (Ap (Vr x) (Vr y))) \<noteq>
       
   213    (Lt (Lcons y (Ap (Vr x) (Vr y)) (Lcons x (Vr x) Lnil)) (Ap (Vr x) (Vr y)))"
       
   214   apply (simp add: alphas trm_lts.eq_iff)
       
   215   done
       
   216 
       
   217 
       
   218 lemma lets_not_ok1:
       
   219   "x \<noteq> y \<Longrightarrow>
       
   220    (Lt (Lcons x (Vr x) (Lcons y (Vr y) Lnil)) (Ap (Vr x) (Vr y))) \<noteq>
       
   221    (Lt (Lcons y (Vr x) (Lcons x (Vr y) Lnil)) (Ap (Vr x) (Vr y)))"
       
   222   apply (simp add: alphas trm_lts.eq_iff fresh_star_def eqvts)
       
   223   done
       
   224 
       
   225 lemma lets_nok:
       
   226   "x \<noteq> y \<Longrightarrow> x \<noteq> z \<Longrightarrow> z \<noteq> y \<Longrightarrow>
       
   227    (Lt (Lcons x (Ap (Vr z) (Vr z)) (Lcons y (Vr z) Lnil)) (Ap (Vr x) (Vr y))) \<noteq>
       
   228    (Lt (Lcons y (Vr z) (Lcons x (Ap (Vr z) (Vr z)) Lnil)) (Ap (Vr x) (Vr y)))"
       
   229   apply (simp add: alphas trm_lts.eq_iff fresh_star_def)
       
   230   done
       
   231 
       
   232 
       
   233 end
       
   234 
       
   235 
       
   236