src/HOL/Datatype_Universe.ML
changeset 15388 aa785cea8fff
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     1 (*  Title:      HOL/Datatype_Universe.ML
       
     2     ID:         $Id$
       
     3     Author:     Lawrence C Paulson, Cambridge University Computer Laboratory
       
     4     Copyright   1991  University of Cambridge
       
     5 *)
       
     6 
       
     7 (** apfst -- can be used in similar type definitions **)
       
     8 
       
     9 Goalw [apfst_def] "apfst f (a,b) = (f(a),b)";
       
    10 by (rtac split_conv 1);
       
    11 qed "apfst_conv";
       
    12 
       
    13 val [major,minor] = Goal
       
    14     "[| q = apfst f p;  !!x y. [| p = (x,y);  q = (f(x),y) |] ==> R \
       
    15 \    |] ==> R";
       
    16 by (rtac PairE 1);
       
    17 by (rtac minor 1);
       
    18 by (assume_tac 1);
       
    19 by (rtac (major RS trans) 1);
       
    20 by (etac ssubst 1);
       
    21 by (rtac apfst_conv 1);
       
    22 qed "apfst_convE";
       
    23 
       
    24 (** Push -- an injection, analogous to Cons on lists **)
       
    25 
       
    26 Goalw [Push_def] "Push i f = Push j g  ==> i=j";
       
    27 by (etac (fun_cong RS box_equals) 1);
       
    28 by (rtac nat_case_0 1);
       
    29 by (rtac nat_case_0 1);
       
    30 qed "Push_inject1";
       
    31 
       
    32 Goalw [Push_def] "Push i f = Push j g  ==> f=g";
       
    33 by (rtac (ext RS box_equals) 1);
       
    34 by (etac fun_cong 1);
       
    35 by (rtac (nat_case_Suc RS ext) 1);
       
    36 by (rtac (nat_case_Suc RS ext) 1);
       
    37 qed "Push_inject2";
       
    38 
       
    39 val [major,minor] = Goal
       
    40     "[| Push i f =Push j g;  [| i=j;  f=g |] ==> P \
       
    41 \    |] ==> P";
       
    42 by (rtac ((major RS Push_inject2) RS ((major RS Push_inject1) RS minor)) 1);
       
    43 qed "Push_inject";
       
    44 
       
    45 Goalw [Push_def] "Push (Inr (Suc k)) f = (%z. Inr 0) ==> P";
       
    46 by (rtac Suc_neq_Zero 1);
       
    47 by (etac (fun_cong RS box_equals RS Inr_inject) 1);
       
    48 by (rtac nat_case_0 1);
       
    49 by (rtac refl 1);
       
    50 qed "Push_neq_K0";
       
    51 
       
    52 (*** Isomorphisms ***)
       
    53 
       
    54 Goal "inj(Rep_Node)";
       
    55 by (rtac inj_inverseI 1);       (*cannot combine by RS: multiple unifiers*)
       
    56 by (rtac Rep_Node_inverse 1);
       
    57 qed "inj_Rep_Node";
       
    58 
       
    59 Goal "inj_on Abs_Node Node";
       
    60 by (rtac inj_on_inverseI 1);
       
    61 by (etac Abs_Node_inverse 1);
       
    62 qed "inj_on_Abs_Node";
       
    63 
       
    64 bind_thm ("Abs_Node_inj", inj_on_Abs_Node RS inj_onD);
       
    65 
       
    66 
       
    67 (*** Introduction rules for Node ***)
       
    68 
       
    69 Goalw [Node_def] "(%k. Inr 0, a) : Node";
       
    70 by (Blast_tac 1);
       
    71 qed "Node_K0_I";
       
    72 
       
    73 Goalw [Node_def,Push_def]
       
    74     "p: Node ==> apfst (Push i) p : Node";
       
    75 by (fast_tac (claset() addSIs [apfst_conv, nat_case_Suc RS trans]) 1);
       
    76 qed "Node_Push_I";
       
    77 
       
    78 
       
    79 (*** Distinctness of constructors ***)
       
    80 
       
    81 (** Scons vs Atom **)
       
    82 
       
    83 Goalw [Atom_def,Scons_def,Push_Node_def,One_nat_def]
       
    84  "Scons M N ~= Atom(a)";
       
    85 by (rtac notI 1);
       
    86 by (etac (equalityD2 RS subsetD RS UnE) 1);
       
    87 by (rtac singletonI 1);
       
    88 by (REPEAT (eresolve_tac [imageE, Abs_Node_inj RS apfst_convE, 
       
    89                           Pair_inject, sym RS Push_neq_K0] 1
       
    90      ORELSE resolve_tac [Node_K0_I, Rep_Node RS Node_Push_I] 1));
       
    91 qed "Scons_not_Atom";
       
    92 bind_thm ("Atom_not_Scons", Scons_not_Atom RS not_sym);
       
    93 
       
    94 
       
    95 (*** Injectiveness ***)
       
    96 
       
    97 (** Atomic nodes **)
       
    98 
       
    99 Goalw [Atom_def] "inj(Atom)";
       
   100 by (blast_tac (claset() addSIs [injI, Node_K0_I] addSDs [Abs_Node_inj]) 1);
       
   101 qed "inj_Atom";
       
   102 bind_thm ("Atom_inject", inj_Atom RS injD);
       
   103 
       
   104 Goal "(Atom(a)=Atom(b)) = (a=b)";
       
   105 by (blast_tac (claset() addSDs [Atom_inject]) 1);
       
   106 qed "Atom_Atom_eq";
       
   107 AddIffs [Atom_Atom_eq];
       
   108 
       
   109 Goalw [Leaf_def,o_def] "inj(Leaf)";
       
   110 by (rtac injI 1);
       
   111 by (etac (Atom_inject RS Inl_inject) 1);
       
   112 qed "inj_Leaf";
       
   113 
       
   114 bind_thm ("Leaf_inject", inj_Leaf RS injD);
       
   115 AddSDs [Leaf_inject];
       
   116 
       
   117 Goalw [Numb_def,o_def] "inj(Numb)";
       
   118 by (rtac injI 1);
       
   119 by (etac (Atom_inject RS Inr_inject) 1);
       
   120 qed "inj_Numb";
       
   121 
       
   122 bind_thm ("Numb_inject", inj_Numb RS injD);
       
   123 AddSDs [Numb_inject];
       
   124 
       
   125 (** Injectiveness of Push_Node **)
       
   126 
       
   127 val [major,minor] = Goalw [Push_Node_def]
       
   128     "[| Push_Node i m =Push_Node j n;  [| i=j;  m=n |] ==> P \
       
   129 \    |] ==> P";
       
   130 by (rtac (major RS Abs_Node_inj RS apfst_convE) 1);
       
   131 by (REPEAT (resolve_tac [Rep_Node RS Node_Push_I] 1));
       
   132 by (etac (sym RS apfst_convE) 1);
       
   133 by (rtac minor 1);
       
   134 by (etac Pair_inject 1);
       
   135 by (etac (Push_inject1 RS sym) 1);
       
   136 by (rtac (inj_Rep_Node RS injD) 1);
       
   137 by (etac trans 1);
       
   138 by (safe_tac (claset() addSEs [Push_inject,sym]));
       
   139 qed "Push_Node_inject";
       
   140 
       
   141 
       
   142 (** Injectiveness of Scons **)
       
   143 
       
   144 Goalw [Scons_def,One_nat_def] "Scons M N <= Scons M' N' ==> M<=M'";
       
   145 by (blast_tac (claset() addSDs [Push_Node_inject]) 1);
       
   146 qed "Scons_inject_lemma1";
       
   147 
       
   148 Goalw [Scons_def,One_nat_def] "Scons M N <= Scons M' N' ==> N<=N'";
       
   149 by (blast_tac (claset() addSDs [Push_Node_inject]) 1);
       
   150 qed "Scons_inject_lemma2";
       
   151 
       
   152 Goal "Scons M N = Scons M' N' ==> M=M'";
       
   153 by (etac equalityE 1);
       
   154 by (REPEAT (ares_tac [equalityI, Scons_inject_lemma1] 1));
       
   155 qed "Scons_inject1";
       
   156 
       
   157 Goal "Scons M N = Scons M' N' ==> N=N'";
       
   158 by (etac equalityE 1);
       
   159 by (REPEAT (ares_tac [equalityI, Scons_inject_lemma2] 1));
       
   160 qed "Scons_inject2";
       
   161 
       
   162 val [major,minor] = Goal
       
   163     "[| Scons M N = Scons M' N';  [| M=M';  N=N' |] ==> P \
       
   164 \    |] ==> P";
       
   165 by (rtac ((major RS Scons_inject2) RS ((major RS Scons_inject1) RS minor)) 1);
       
   166 qed "Scons_inject";
       
   167 
       
   168 Goal "(Scons M N = Scons M' N') = (M=M' & N=N')";
       
   169 by (blast_tac (claset() addSEs [Scons_inject]) 1);
       
   170 qed "Scons_Scons_eq";
       
   171 
       
   172 (*** Distinctness involving Leaf and Numb ***)
       
   173 
       
   174 (** Scons vs Leaf **)
       
   175 
       
   176 Goalw [Leaf_def,o_def] "Scons M N ~= Leaf(a)";
       
   177 by (rtac Scons_not_Atom 1);
       
   178 qed "Scons_not_Leaf";
       
   179 bind_thm ("Leaf_not_Scons", Scons_not_Leaf RS not_sym);
       
   180 
       
   181 AddIffs [Scons_not_Leaf, Leaf_not_Scons];
       
   182 
       
   183 
       
   184 (** Scons vs Numb **)
       
   185 
       
   186 Goalw [Numb_def,o_def] "Scons M N ~= Numb(k)";
       
   187 by (rtac Scons_not_Atom 1);
       
   188 qed "Scons_not_Numb";
       
   189 bind_thm ("Numb_not_Scons", Scons_not_Numb RS not_sym);
       
   190 
       
   191 AddIffs [Scons_not_Numb, Numb_not_Scons];
       
   192 
       
   193 
       
   194 (** Leaf vs Numb **)
       
   195 
       
   196 Goalw [Leaf_def,Numb_def] "Leaf(a) ~= Numb(k)";
       
   197 by (simp_tac (simpset() addsimps [Inl_not_Inr]) 1);
       
   198 qed "Leaf_not_Numb";
       
   199 bind_thm ("Numb_not_Leaf", Leaf_not_Numb RS not_sym);
       
   200 
       
   201 AddIffs [Leaf_not_Numb, Numb_not_Leaf];
       
   202 
       
   203 
       
   204 (*** ndepth -- the depth of a node ***)
       
   205 
       
   206 Addsimps [apfst_conv];
       
   207 AddIffs  [Scons_not_Atom, Atom_not_Scons, Scons_Scons_eq];
       
   208 
       
   209 
       
   210 Goalw [ndepth_def] "ndepth (Abs_Node(%k. Inr 0, x)) = 0";
       
   211 by (EVERY1[stac (Node_K0_I RS Abs_Node_inverse), stac split_conv]);
       
   212 by (rtac Least_equality 1);
       
   213 by Auto_tac;  
       
   214 qed "ndepth_K0";
       
   215 
       
   216 Goal "nat_case (Inr (Suc i)) f k = Inr 0 --> Suc(LEAST x. f x = Inr 0) <= k";
       
   217 by (induct_tac "k" 1);
       
   218 by (ALLGOALS Simp_tac);
       
   219 by (rtac impI 1); 
       
   220 by (etac Least_le 1);
       
   221 val lemma = result();
       
   222 
       
   223 Goalw [ndepth_def,Push_Node_def]
       
   224     "ndepth (Push_Node (Inr (Suc i)) n) = Suc(ndepth(n))";
       
   225 by (stac (Rep_Node RS Node_Push_I RS Abs_Node_inverse) 1);
       
   226 by (cut_facts_tac [rewrite_rule [Node_def] Rep_Node] 1);
       
   227 by Safe_tac;
       
   228 by (etac ssubst 1);  (*instantiates type variables!*)
       
   229 by (Simp_tac 1);
       
   230 by (rtac Least_equality 1);
       
   231 by (rewtac Push_def);
       
   232 by (auto_tac (claset(), simpset() addsimps [lemma]));  
       
   233 by (etac LeastI 1);
       
   234 qed "ndepth_Push_Node";
       
   235 
       
   236 
       
   237 (*** ntrunc applied to the various node sets ***)
       
   238 
       
   239 Goalw [ntrunc_def] "ntrunc 0 M = {}";
       
   240 by (Blast_tac 1);
       
   241 qed "ntrunc_0";
       
   242 
       
   243 Goalw [Atom_def,ntrunc_def] "ntrunc (Suc k) (Atom a) = Atom(a)";
       
   244 by (fast_tac (claset() addss (simpset() addsimps [ndepth_K0])) 1);
       
   245 qed "ntrunc_Atom";
       
   246 
       
   247 Goalw [Leaf_def,o_def] "ntrunc (Suc k) (Leaf a) = Leaf(a)";
       
   248 by (rtac ntrunc_Atom 1);
       
   249 qed "ntrunc_Leaf";
       
   250 
       
   251 Goalw [Numb_def,o_def] "ntrunc (Suc k) (Numb i) = Numb(i)";
       
   252 by (rtac ntrunc_Atom 1);
       
   253 qed "ntrunc_Numb";
       
   254 
       
   255 Goalw [Scons_def,ntrunc_def,One_nat_def]
       
   256     "ntrunc (Suc k) (Scons M N) = Scons (ntrunc k M) (ntrunc k N)";
       
   257 by (safe_tac (claset() addSIs [imageI]));
       
   258 by (REPEAT (stac ndepth_Push_Node 3 THEN etac Suc_mono 3));
       
   259 by (REPEAT (rtac Suc_less_SucD 1 THEN 
       
   260             rtac (ndepth_Push_Node RS subst) 1 THEN 
       
   261             assume_tac 1));
       
   262 qed "ntrunc_Scons";
       
   263 
       
   264 Addsimps [ntrunc_0, ntrunc_Atom, ntrunc_Leaf, ntrunc_Numb, ntrunc_Scons];
       
   265 
       
   266 
       
   267 (** Injection nodes **)
       
   268 
       
   269 Goalw [In0_def] "ntrunc (Suc 0) (In0 M) = {}";
       
   270 by (Simp_tac 1);
       
   271 by (rewtac Scons_def);
       
   272 by (Blast_tac 1);
       
   273 qed "ntrunc_one_In0";
       
   274 
       
   275 Goalw [In0_def]
       
   276     "ntrunc (Suc (Suc k)) (In0 M) = In0 (ntrunc (Suc k) M)";
       
   277 by (Simp_tac 1);
       
   278 qed "ntrunc_In0";
       
   279 
       
   280 Goalw [In1_def] "ntrunc (Suc 0) (In1 M) = {}";
       
   281 by (Simp_tac 1);
       
   282 by (rewtac Scons_def);
       
   283 by (Blast_tac 1);
       
   284 qed "ntrunc_one_In1";
       
   285 
       
   286 Goalw [In1_def]
       
   287     "ntrunc (Suc (Suc k)) (In1 M) = In1 (ntrunc (Suc k) M)";
       
   288 by (Simp_tac 1);
       
   289 qed "ntrunc_In1";
       
   290 
       
   291 Addsimps [ntrunc_one_In0, ntrunc_In0, ntrunc_one_In1, ntrunc_In1];
       
   292 
       
   293 
       
   294 (*** Cartesian Product ***)
       
   295 
       
   296 Goalw [uprod_def] "[| M:A;  N:B |] ==> Scons M N : uprod A B";
       
   297 by (REPEAT (ares_tac [singletonI,UN_I] 1));
       
   298 qed "uprodI";
       
   299 
       
   300 (*The general elimination rule*)
       
   301 val major::prems = Goalw [uprod_def]
       
   302     "[| c : uprod A B;  \
       
   303 \       !!x y. [| x:A;  y:B;  c = Scons x y |] ==> P \
       
   304 \    |] ==> P";
       
   305 by (cut_facts_tac [major] 1);
       
   306 by (REPEAT (eresolve_tac [asm_rl,singletonE,UN_E] 1
       
   307      ORELSE resolve_tac prems 1));
       
   308 qed "uprodE";
       
   309 
       
   310 (*Elimination of a pair -- introduces no eigenvariables*)
       
   311 val prems = Goal
       
   312     "[| Scons M N : uprod A B;      [| M:A;  N:B |] ==> P   \
       
   313 \    |] ==> P";
       
   314 by (rtac uprodE 1);
       
   315 by (REPEAT (ares_tac prems 1 ORELSE eresolve_tac [Scons_inject,ssubst] 1));
       
   316 qed "uprodE2";
       
   317 
       
   318 
       
   319 (*** Disjoint Sum ***)
       
   320 
       
   321 Goalw [usum_def] "M:A ==> In0(M) : usum A B";
       
   322 by (Blast_tac 1);
       
   323 qed "usum_In0I";
       
   324 
       
   325 Goalw [usum_def] "N:B ==> In1(N) : usum A B";
       
   326 by (Blast_tac 1);
       
   327 qed "usum_In1I";
       
   328 
       
   329 val major::prems = Goalw [usum_def]
       
   330     "[| u : usum A B;  \
       
   331 \       !!x. [| x:A;  u=In0(x) |] ==> P; \
       
   332 \       !!y. [| y:B;  u=In1(y) |] ==> P \
       
   333 \    |] ==> P";
       
   334 by (rtac (major RS UnE) 1);
       
   335 by (REPEAT (rtac refl 1 
       
   336      ORELSE eresolve_tac (prems@[imageE,ssubst]) 1));
       
   337 qed "usumE";
       
   338 
       
   339 
       
   340 (** Injection **)
       
   341 
       
   342 Goalw [In0_def,In1_def,One_nat_def] "In0(M) ~= In1(N)";
       
   343 by (rtac notI 1);
       
   344 by (etac (Scons_inject1 RS Numb_inject RS Zero_neq_Suc) 1);
       
   345 qed "In0_not_In1";
       
   346 
       
   347 bind_thm ("In1_not_In0", In0_not_In1 RS not_sym);
       
   348 
       
   349 AddIffs [In0_not_In1, In1_not_In0];
       
   350 
       
   351 Goalw [In0_def] "In0(M) = In0(N) ==>  M=N";
       
   352 by (etac (Scons_inject2) 1);
       
   353 qed "In0_inject";
       
   354 
       
   355 Goalw [In1_def] "In1(M) = In1(N) ==>  M=N";
       
   356 by (etac (Scons_inject2) 1);
       
   357 qed "In1_inject";
       
   358 
       
   359 Goal "(In0 M = In0 N) = (M=N)";
       
   360 by (blast_tac (claset() addSDs [In0_inject]) 1);
       
   361 qed "In0_eq";
       
   362 
       
   363 Goal "(In1 M = In1 N) = (M=N)";
       
   364 by (blast_tac (claset() addSDs [In1_inject]) 1);
       
   365 qed "In1_eq";
       
   366 
       
   367 AddIffs [In0_eq, In1_eq];
       
   368 
       
   369 Goal "inj In0";
       
   370 by (blast_tac (claset() addSIs [injI]) 1);
       
   371 qed "inj_In0";
       
   372 
       
   373 Goal "inj In1";
       
   374 by (blast_tac (claset() addSIs [injI]) 1);
       
   375 qed "inj_In1";
       
   376 
       
   377 
       
   378 (*** Function spaces ***)
       
   379 
       
   380 Goalw [Lim_def] "Lim f = Lim g ==> f = g";
       
   381 by (rtac ext 1);
       
   382 by (blast_tac (claset() addSEs [Push_Node_inject]) 1);
       
   383 qed "Lim_inject";
       
   384 
       
   385 
       
   386 (*** proving equality of sets and functions using ntrunc ***)
       
   387 
       
   388 Goalw [ntrunc_def] "ntrunc k M <= M";
       
   389 by (Blast_tac 1);
       
   390 qed "ntrunc_subsetI";
       
   391 
       
   392 val [major] = Goalw [ntrunc_def] "(!!k. ntrunc k M <= N) ==> M<=N";
       
   393 by (blast_tac (claset() addIs [less_add_Suc1, less_add_Suc2, 
       
   394 			       major RS subsetD]) 1);
       
   395 qed "ntrunc_subsetD";
       
   396 
       
   397 (*A generalized form of the take-lemma*)
       
   398 val [major] = Goal "(!!k. ntrunc k M = ntrunc k N) ==> M=N";
       
   399 by (rtac equalityI 1);
       
   400 by (ALLGOALS (rtac ntrunc_subsetD));
       
   401 by (ALLGOALS (rtac (ntrunc_subsetI RSN (2, subset_trans))));
       
   402 by (rtac (major RS equalityD1) 1);
       
   403 by (rtac (major RS equalityD2) 1);
       
   404 qed "ntrunc_equality";
       
   405 
       
   406 val [major] = Goalw [o_def]
       
   407     "[| !!k. (ntrunc(k) o h1) = (ntrunc(k) o h2) |] ==> h1=h2";
       
   408 by (rtac (ntrunc_equality RS ext) 1);
       
   409 by (rtac (major RS fun_cong) 1);
       
   410 qed "ntrunc_o_equality";
       
   411 
       
   412 (*** Monotonicity ***)
       
   413 
       
   414 Goalw [uprod_def] "[| A<=A';  B<=B' |] ==> uprod A B <= uprod A' B'";
       
   415 by (Blast_tac 1);
       
   416 qed "uprod_mono";
       
   417 
       
   418 Goalw [usum_def] "[| A<=A';  B<=B' |] ==> usum A B <= usum A' B'";
       
   419 by (Blast_tac 1);
       
   420 qed "usum_mono";
       
   421 
       
   422 Goalw [Scons_def] "[| M<=M';  N<=N' |] ==> Scons M N <= Scons M' N'";
       
   423 by (Blast_tac 1);
       
   424 qed "Scons_mono";
       
   425 
       
   426 Goalw [In0_def] "M<=N ==> In0(M) <= In0(N)";
       
   427 by (REPEAT (ares_tac [subset_refl,Scons_mono] 1));
       
   428 qed "In0_mono";
       
   429 
       
   430 Goalw [In1_def] "M<=N ==> In1(M) <= In1(N)";
       
   431 by (REPEAT (ares_tac [subset_refl,Scons_mono] 1));
       
   432 qed "In1_mono";
       
   433 
       
   434 
       
   435 (*** Split and Case ***)
       
   436 
       
   437 Goalw [Split_def] "Split c (Scons M N) = c M N";
       
   438 by (Blast_tac  1);
       
   439 qed "Split";
       
   440 
       
   441 Goalw [Case_def] "Case c d (In0 M) = c(M)";
       
   442 by (Blast_tac 1);
       
   443 qed "Case_In0";
       
   444 
       
   445 Goalw [Case_def] "Case c d (In1 N) = d(N)";
       
   446 by (Blast_tac 1);
       
   447 qed "Case_In1";
       
   448 
       
   449 Addsimps [Split, Case_In0, Case_In1];
       
   450 
       
   451 
       
   452 (**** UN x. B(x) rules ****)
       
   453 
       
   454 Goalw [ntrunc_def] "ntrunc k (UN x. f(x)) = (UN x. ntrunc k (f x))";
       
   455 by (Blast_tac 1);
       
   456 qed "ntrunc_UN1";
       
   457 
       
   458 Goalw [Scons_def] "Scons (UN x. f x) M = (UN x. Scons (f x) M)";
       
   459 by (Blast_tac 1);
       
   460 qed "Scons_UN1_x";
       
   461 
       
   462 Goalw [Scons_def] "Scons M (UN x. f x) = (UN x. Scons M (f x))";
       
   463 by (Blast_tac 1);
       
   464 qed "Scons_UN1_y";
       
   465 
       
   466 Goalw [In0_def] "In0(UN x. f(x)) = (UN x. In0(f(x)))";
       
   467 by (rtac Scons_UN1_y 1);
       
   468 qed "In0_UN1";
       
   469 
       
   470 Goalw [In1_def] "In1(UN x. f(x)) = (UN x. In1(f(x)))";
       
   471 by (rtac Scons_UN1_y 1);
       
   472 qed "In1_UN1";
       
   473 
       
   474 
       
   475 (*** Equality for Cartesian Product ***)
       
   476 
       
   477 Goalw [dprod_def]
       
   478     "[| (M,M'):r;  (N,N'):s |] ==> (Scons M N, Scons M' N') : dprod r s";
       
   479 by (Blast_tac 1);
       
   480 qed "dprodI";
       
   481 
       
   482 (*The general elimination rule*)
       
   483 val major::prems = Goalw [dprod_def]
       
   484     "[| c : dprod r s;  \
       
   485 \       !!x y x' y'. [| (x,x') : r;  (y,y') : s;  c = (Scons x y, Scons x' y') |] ==> P \
       
   486 \    |] ==> P";
       
   487 by (cut_facts_tac [major] 1);
       
   488 by (REPEAT_FIRST (eresolve_tac [asm_rl, UN_E, mem_splitE, singletonE]));
       
   489 by (REPEAT (ares_tac prems 1 ORELSE hyp_subst_tac 1));
       
   490 qed "dprodE";
       
   491 
       
   492 
       
   493 (*** Equality for Disjoint Sum ***)
       
   494 
       
   495 Goalw [dsum_def]  "(M,M'):r ==> (In0(M), In0(M')) : dsum r s";
       
   496 by (Blast_tac 1);
       
   497 qed "dsum_In0I";
       
   498 
       
   499 Goalw [dsum_def]  "(N,N'):s ==> (In1(N), In1(N')) : dsum r s";
       
   500 by (Blast_tac 1);
       
   501 qed "dsum_In1I";
       
   502 
       
   503 val major::prems = Goalw [dsum_def]
       
   504     "[| w : dsum r s;  \
       
   505 \       !!x x'. [| (x,x') : r;  w = (In0(x), In0(x')) |] ==> P; \
       
   506 \       !!y y'. [| (y,y') : s;  w = (In1(y), In1(y')) |] ==> P \
       
   507 \    |] ==> P";
       
   508 by (cut_facts_tac [major] 1);
       
   509 by (REPEAT_FIRST (eresolve_tac [asm_rl, UN_E, UnE, mem_splitE, singletonE]));
       
   510 by (DEPTH_SOLVE (ares_tac prems 1 ORELSE hyp_subst_tac 1));
       
   511 qed "dsumE";
       
   512 
       
   513 AddSIs [uprodI, dprodI];
       
   514 AddIs  [usum_In0I, usum_In1I, dsum_In0I, dsum_In1I];
       
   515 AddSEs [uprodE, dprodE, usumE, dsumE];
       
   516 
       
   517 
       
   518 (*** Monotonicity ***)
       
   519 
       
   520 Goal "[| r<=r';  s<=s' |] ==> dprod r s <= dprod r' s'";
       
   521 by (Blast_tac 1);
       
   522 qed "dprod_mono";
       
   523 
       
   524 Goal "[| r<=r';  s<=s' |] ==> dsum r s <= dsum r' s'";
       
   525 by (Blast_tac 1);
       
   526 qed "dsum_mono";
       
   527 
       
   528 
       
   529 (*** Bounding theorems ***)
       
   530 
       
   531 Goal "(dprod (A <*> B) (C <*> D)) <= (uprod A C) <*> (uprod B D)";
       
   532 by (Blast_tac 1);
       
   533 qed "dprod_Sigma";
       
   534 
       
   535 bind_thm ("dprod_subset_Sigma", [dprod_mono, dprod_Sigma] MRS subset_trans |> standard);
       
   536 
       
   537 (*Dependent version*)
       
   538 Goal "(dprod (Sigma A B) (Sigma C D)) <= Sigma (uprod A C) (Split (%x y. uprod (B x) (D y)))";
       
   539 by Safe_tac;
       
   540 by (stac Split 1);
       
   541 by (Blast_tac 1);
       
   542 qed "dprod_subset_Sigma2";
       
   543 
       
   544 Goal "(dsum (A <*> B) (C <*> D)) <= (usum A C) <*> (usum B D)";
       
   545 by (Blast_tac 1);
       
   546 qed "dsum_Sigma";
       
   547 
       
   548 bind_thm ("dsum_subset_Sigma", [dsum_mono, dsum_Sigma] MRS subset_trans |> standard);
       
   549 
       
   550 
       
   551 (*** Domain ***)
       
   552 
       
   553 Goal "Domain (dprod r s) = uprod (Domain r) (Domain s)";
       
   554 by Auto_tac;
       
   555 qed "Domain_dprod";
       
   556 
       
   557 Goal "Domain (dsum r s) = usum (Domain r) (Domain s)";
       
   558 by Auto_tac;
       
   559 qed "Domain_dsum";
       
   560 
       
   561 Addsimps [Domain_dprod, Domain_dsum];