more work on simple_inductive
authorChristian Urban <urbanc@in.tum.de>
Tue, 10 Mar 2009 13:20:46 +0000
changeset 164 3f617d7a2691
parent 163 2319cff107f0
child 165 890fbfef6d6b
more work on simple_inductive
CookBook/Appendix.thy
CookBook/Package/Ind_Code.thy
CookBook/Package/Simple_Inductive_Package.thy
CookBook/Package/simple_inductive_package.ML
cookbook.pdf
--- a/CookBook/Appendix.thy	Sun Mar 08 20:53:00 2009 +0000
+++ b/CookBook/Appendix.thy	Tue Mar 10 13:20:46 2009 +0000
@@ -18,6 +18,12 @@
   user space type systems (in the form that already exists)
 
   unification and typing algorithms
+
+  useful datastructures:
+
+  discrimination nets
+
+  association lists
 *}
 
 end
--- a/CookBook/Package/Ind_Code.thy	Sun Mar 08 20:53:00 2009 +0000
+++ b/CookBook/Package/Ind_Code.thy	Tue Mar 10 13:20:46 2009 +0000
@@ -1,26 +1,178 @@
 theory Ind_Code
-imports "../Base" Simple_Inductive_Package
+imports "../Base" Simple_Inductive_Package Ind_Prelims
 begin
 
+section {* Code *}
+
+subsection {* Definitions *}
+
+text {*
+  If we give it a term and a constant name, it will define the 
+  constant as the term. 
+*}
+
+ML{*fun make_defs ((binding, syn), trm) lthy =
+let 
+  val arg = ((binding, syn), (Attrib.empty_binding, trm))
+  val ((_, (_ , thm)), lthy) = LocalTheory.define Thm.internalK arg lthy
+in 
+  (thm, lthy) 
+end*}
+
+text {*
+  Returns the definition and the local theory in which this definition has 
+  been made. What is @{ML Thm.internalK}?
+*}
+
+ML {*let
+  val lthy = TheoryTarget.init NONE @{theory}
+in
+  make_defs ((Binding.name "MyTrue", NoSyn), @{term "True"}) lthy
+end*}
+
+text {*
+  Why is the output of MyTrue blue?
+*}
+
+text {*
+  Constructs the term for the definition: the main arguments are a predicate
+  and the types of the arguments, it also expects orules which are the 
+  intro rules in the object logic; preds which are all predicates. returns the
+  term.
+*}
+
+ML %linenosgray{*fun defs_aux lthy orules preds (pred, arg_types) =
+let 
+  fun mk_all x P = HOLogic.all_const (fastype_of x) $ lambda x P
+
+  val fresh_args = 
+        arg_types 
+        |> map (pair "z")
+        |> Variable.variant_frees lthy orules 
+        |> map Free
+in
+  list_comb (pred, fresh_args)
+  |> fold_rev (curry HOLogic.mk_imp) orules
+  |> fold_rev mk_all preds
+  |> fold_rev lambda fresh_args 
+end*}
+
+text {*
+  The lines 5-9 produce fresh arguments with which the predicate can be applied.
+  For this it pairs every type with a string @{text [quotes] "z"} (Line 7); then 
+  generates variants for all these strings (names) so that they are unique w.r.t.~to 
+  the intro rules; in Line 9 it generates the corresponding variable terms for these 
+  unique names.
+
+  The unique free variables are applied to the predicate (Line 11); then
+  the intro rules are attached as preconditions (Line 12); in Line 13 we
+  quantify over all predicates; and in line 14 we just abstract over all
+  the (fresh) arguments of the predicate.
+*}
+
 text {*
-  What does the @{ML Thm.internalK} do, in the LocalTheory.define Thm.internalK?
+  The arguments of the main function for the definitions are 
+  the intro rules; the predicates and their names, their syntax 
+  annotations and the argument types of each predicate. It  
+  returns a theorem list (the definitions) and a local
+  theory where the definitions are made
+*}
+
+ML %linenosgray{*fun definitions rules preds prednames syns arg_typss lthy =
+let
+  val thy = ProofContext.theory_of lthy
+  val orules = map (ObjectLogic.atomize_term thy) rules
+  val defs = map (defs_aux lthy orules preds) (preds ~~ arg_typss) 
+in
+  fold_map make_defs (prednames ~~ syns ~~ defs) lthy
+end*}
+
+text {*
+  In line 4 we generate the intro rules in the object logic; for this we have to 
+  obtain the theory behind the local theory (Line 3); with this we can
+  call @{ML defs_aux} to generate the terms for the left-hand sides.
+  The actual definitions are made in Line 7.  
+*}
+
+subsection {* Introduction Rules *}
+
+ML{*fun inst_spec ct = 
+ Drule.instantiate' [SOME (ctyp_of_term ct)] [NONE, SOME ct] @{thm spec}*}
+
+text {*
+  Instantiates the @{text "x"} in @{thm spec[no_vars]} with a @{ML_type cterm}.
+*}
+
+text {*
+  Instantiates universal qantifications in the premises
+*}
+
+lemma "\<forall>x\<^isub>1 x\<^isub>2 x\<^isub>3. P (x\<^isub>1::nat) (x\<^isub>2::nat) (x\<^isub>3::nat) \<Longrightarrow> True"
+apply (tactic {* EVERY' (map (dtac o inst_spec) 
+          [@{cterm "y\<^isub>1::nat"},@{cterm "y\<^isub>2::nat"},@{cterm "y\<^isub>3::nat"}]) 1*})
+(*<*)oops(*>*)
+
+text {*
+  The tactic for proving the induction rules: 
 *}
 
+ML{*fun induction_tac defs prems insts =
+  EVERY1 [ObjectLogic.full_atomize_tac,
+          cut_facts_tac prems,
+          K (rewrite_goals_tac defs),
+          EVERY' (map (dtac o inst_spec) insts),
+          assume_tac]*}
+
+lemma 
+  assumes asm: "even n"
+  shows "P 0 \<Longrightarrow> 
+           (\<And>m. Q m \<Longrightarrow> P (Suc m)) \<Longrightarrow> (\<And>m. P m \<Longrightarrow> Q (Suc m)) \<Longrightarrow> P n"
+apply(tactic {* induction_tac [@{thm even_def}, @{thm odd_def}] [@{thm asm}] 
+  [@{cterm "P::nat\<Rightarrow>bool"}, @{cterm "Q::nat\<Rightarrow>bool"}] *})
+done
+
+ML %linenosgray{*fun inductions rules defs preds Tss lthy1  =
+let
+  val Ps = replicate (length preds) "P"
+  val (newprednames, lthy2) = Variable.variant_fixes Ps lthy1
+  
+  val thy = ProofContext.theory_of lthy2
+
+  val Tss' = map (fn Ts => Ts ---> HOLogic.boolT) Tss
+  val newpreds = map Free (newprednames ~~ Tss')
+  val cnewpreds = map (cterm_of thy) newpreds
+  val rules' = map (subst_free (preds ~~ newpreds)) rules
+
+  fun prove_induction ((pred, newpred), Ts)  =
+  let
+    val zs = replicate (length Ts) "z"
+    val (newargnames, lthy3) = Variable.variant_fixes zs lthy2;
+    val newargs = map Free (newargnames ~~ Ts)
+
+    val prem = HOLogic.mk_Trueprop (list_comb (pred, newargs))
+    val goal = Logic.list_implies 
+         (rules', HOLogic.mk_Trueprop (list_comb (newpred, newargs)))
+  in
+    Goal.prove lthy3 [] [prem] goal
+      (fn {prems, ...} => induction_tac defs prems cnewpreds)
+      |> singleton (ProofContext.export lthy3 lthy1)
+  end 
+in
+  map prove_induction (preds ~~ newpreds ~~ Tss)
+end*}
+
+ML {* Goal.prove  *}
+ML {* singleton *}
+ML {* ProofContext.export *}
 
 text {*
 
-  @{ML_chunk [display,gray] definitions_aux}
-  @{ML_chunk [display,gray,linenos] definitions}
-
 *}
 
 text {*
-
-  @{ML_chunk [display,gray] induction_rules}
+  @{ML_chunk [display,gray] subproof1}
 
-*}
-
-text {*
+  @{ML_chunk [display,gray] subproof2}
 
   @{ML_chunk [display,gray] intro_rules}
 
--- a/CookBook/Package/Simple_Inductive_Package.thy	Sun Mar 08 20:53:00 2009 +0000
+++ b/CookBook/Package/Simple_Inductive_Package.thy	Tue Mar 10 13:20:46 2009 +0000
@@ -1,8 +1,62 @@
 theory Simple_Inductive_Package
-imports Main
-uses ("simple_inductive_package.ML")
+imports Main "../Base"
+uses "simple_inductive_package.ML"
 begin
 
+(*
+simple_inductive
+  trcl :: "('a \<Rightarrow> 'a \<Rightarrow> bool) \<Rightarrow> 'a \<Rightarrow> 'a \<Rightarrow> bool"
+where
+  base: "trcl R x x"
+| step: "trcl R x y \<Longrightarrow> R y z \<Longrightarrow> trcl R x z"
+
+thm trcl_def
+thm trcl.induct
+thm trcl.intros
+
+simple_inductive
+  even and odd
+where
+  even0: "even 0"
+| evenS: "odd n \<Longrightarrow> even (Suc n)"
+| oddS: "even n \<Longrightarrow> odd (Suc n)"
+
+thm even_def odd_def
+thm even.induct odd.induct
+thm even0
+thm evenS
+thm oddS
+thm even_odd.intros
+
+simple_inductive
+  accpart for r :: "'a \<Rightarrow> 'a \<Rightarrow> bool"
+where
+  accpartI: "(\<forall>y. r y x \<longrightarrow> accpart r y) \<Longrightarrow> accpart r x"
+
+thm accpart_def
+thm accpart.induct
+thm accpartI
+
+locale rel =
+  fixes r :: "'a \<Rightarrow> 'a \<Rightarrow> bool"
+
+simple_inductive (in rel) accpart'
+where
+  accpartI': "\<And>x. (\<And>y. r y x \<Longrightarrow> accpart' y) \<Longrightarrow> accpart' x"
+
+
+context rel
+begin
+  thm accpartI'
+  thm accpart'.induct
+end
+
+thm rel.accpartI'
+thm rel.accpart'.induct
+
+
+lemma "True" by simp
+*)
 
 use_chunks "simple_inductive_package.ML"
 
--- a/CookBook/Package/simple_inductive_package.ML	Sun Mar 08 20:53:00 2009 +0000
+++ b/CookBook/Package/simple_inductive_package.ML	Tue Mar 10 13:20:46 2009 +0000
@@ -18,107 +18,143 @@
 structure SimpleInductivePackage: SIMPLE_INDUCTIVE_PACKAGE =
 struct
 
-fun mk_all x P = HOLogic.all_const (fastype_of x) $ lambda x P 
-
-(* @chunk definitions_aux *) 
-fun definitions_aux ((binding, syn), trm) lthy =
+(* @chunk make_definitions *) 
+fun make_defs ((binding, syn), trm) lthy =
 let 
-  val ((_, (_, thm)), lthy) = 
-    LocalTheory.define Thm.internalK ((binding, syn), (Attrib.empty_binding, trm)) lthy
+  val arg = ((binding, syn), (Attrib.empty_binding, trm))
+  val ((_, (_ , thm)), lthy) = LocalTheory.define Thm.internalK arg lthy
 in 
   (thm, lthy) 
 end
 (* @end *)
 
+(* @chunk definitions_aux *) 
+fun defs_aux lthy orules preds params (pred, arg_types) =
+let 
+  fun mk_all x P = HOLogic.all_const (fastype_of x) $ lambda x P 
+
+  val fresh_args = 
+        arg_types 
+        |> map (pair "z")
+        |> Variable.variant_frees lthy orules 
+        |> map Free
+in
+  list_comb (pred, fresh_args)
+  |> fold_rev (curry HOLogic.mk_imp) orules
+  |> fold_rev mk_all preds
+  |> fold_rev lambda (params @ fresh_args) 
+end
+(* @end *)
+
 (* @chunk definitions *) 
-fun definitions params rules preds preds' Tss lthy =
+fun definitions rules params preds prednames syns arg_typess lthy =
 let
   val thy = ProofContext.theory_of lthy
-  val rules' = map (ObjectLogic.atomize_term thy) rules
+  val orules = map (ObjectLogic.atomize_term thy) rules
+  val defs = 
+    map (defs_aux lthy orules preds params) (preds ~~ arg_typess) 
 in
-  fold_map (fn ((((R, _), syn), pred), Ts) =>
-    let 
-      val zs = map Free (Variable.variant_frees lthy rules' (map (pair "z") Ts))
-        
-      val t0 = list_comb (pred, zs);
-      val t1 = fold_rev (curry HOLogic.mk_imp) rules' t0;
-      val t2 = fold_rev mk_all preds' t1;      
-      val t3 = fold_rev lambda (params @ zs) t2;
-    in
-      definitions_aux ((R, syn), t3)
-    end) (preds ~~ preds' ~~ Tss) lthy
+  fold_map make_defs (prednames ~~ syns ~~ defs) lthy
 end
 (* @end *)
 
 fun inst_spec ct = 
   Drule.instantiate' [SOME (ctyp_of_term ct)] [NONE, SOME ct] @{thm spec};
 
+(* @chunk induction_tac *)
+fun induction_tac defs prems insts =
+  EVERY1 [ObjectLogic.full_atomize_tac,
+          cut_facts_tac prems,
+          K (rewrite_goals_tac defs),
+          EVERY' (map (dtac o inst_spec) insts),
+          assume_tac]
+(* @end *)
+
+(* @chunk induction_rules *)
+fun inductions rules defs parnames preds Tss lthy1  =
+let
+  val (_, lthy2) = Variable.add_fixes parnames lthy1
+  
+  val Ps = replicate (length preds) "P"
+  val (newprednames, lthy3) = Variable.variant_fixes Ps lthy2
+
+  val thy = ProofContext.theory_of lthy3			      
+
+  val Tss' = map (fn Ts => Ts ---> HOLogic.boolT) Tss
+  val newpreds = map Free (newprednames ~~ Tss')
+  val cnewpreds = map (cterm_of thy) newpreds
+  val rules' = map (subst_free (preds ~~ newpreds)) rules
+
+  fun prove_induction ((pred, newpred), Ts)  =
+  let
+    val (newargnames, lthy4) = 
+          Variable.variant_fixes (replicate (length Ts) "z") lthy3;
+    val newargs = map Free (newargnames ~~ Ts)
+
+    val prem = HOLogic.mk_Trueprop (list_comb (pred, newargs))
+    val goal = Logic.list_implies 
+         (rules', HOLogic.mk_Trueprop (list_comb (newpred, newargs)))
+  in
+    Goal.prove lthy4 [] [prem] goal
+      (fn {prems, ...} => induction_tac defs prems cnewpreds)
+      |> singleton (ProofContext.export lthy4 lthy1)
+  end 
+in
+  map prove_induction (preds ~~ newpreds ~~ Tss)
+end
+(* @end *)
+
 val all_elims = fold (fn ct => fn th => th RS inst_spec ct);
 val imp_elims = fold (fn th => fn th' => [th', th] MRS @{thm mp});
 
 
-(* @chunk induction_rules *)
-fun INDUCTION rules preds' Tss defs lthy1 lthy2 =
-let
-  val (Pnames, lthy3) = Variable.variant_fixes (replicate (length preds') "P") lthy2;
-  val Ps = map (fn (s, Ts) => Free (s, Ts ---> HOLogic.boolT)) (Pnames ~~ Tss);
-  val cPs = map (cterm_of (ProofContext.theory_of lthy3)) Ps;
-  val rules'' = map (subst_free (preds' ~~ Ps)) rules;
-
-  fun prove_indrule ((R, P), Ts)  =
+(* @chunk subproof1 *) 
+fun subproof2 prem params2 prems2 =  
+ SUBPROOF (fn {prems, ...} =>
   let
-    val (znames, lthy4) = Variable.variant_fixes (replicate (length Ts) "z") lthy3;
-    val zs = map Free (znames ~~ Ts)
+    val prem' = prems MRS prem;
+    val prem'' = 
+       case prop_of prem' of
+           _ $ (Const (@{const_name All}, _) $ _) =>
+             prem' |> all_elims params2 
+                   |> imp_elims prems2
+         | _ => prem';
+  in 
+    rtac prem'' 1 
+  end)
+(* @end *)
 
-    val prem = HOLogic.mk_Trueprop (list_comb (R, zs))
-    val goal = Logic.list_implies (rules'', HOLogic.mk_Trueprop (list_comb (P, zs)))
+(* @chunk subproof2 *) 
+fun subproof1 rules preds i = 
+ SUBPROOF (fn {params, prems, context = ctxt', ...} =>
+  let
+    val (prems1, prems2) = chop (length prems - length rules) prems;
+    val (params1, params2) = chop (length params - length preds) params;
   in
-    Goal.prove lthy4 [] [prem] goal
-      (fn {prems, ...} => EVERY1
-         ([ObjectLogic.full_atomize_tac,
-           cut_facts_tac prems,
-           K (rewrite_goals_tac defs)] @
-          map (fn ct => dtac (inst_spec ct)) cPs @
-          [assume_tac])) |>
-       singleton (ProofContext.export lthy4 lthy1)
-  end;
-in
-      map prove_indrule (preds' ~~ Ps ~~ Tss)
-  end
+    rtac (ObjectLogic.rulify (all_elims params1 (nth prems2 i))) 1 
+    THEN
+    EVERY1 (map (fn prem => subproof2 prem params2 prems2 ctxt') prems1)
+  end)
 (* @end *)
 
 (* @chunk intro_rules *) 
-fun INTROS rules preds' defs lthy1 lthy2 = 
+fun INTROS rules parnames preds defs lthy1 = 
 let
-  fun prove_intro (i, r) =
-      Goal.prove lthy2 [] [] r
-        (fn {prems, context = ctxt} => EVERY
-           [ObjectLogic.rulify_tac 1,
-            rewrite_goals_tac defs,
-            REPEAT (resolve_tac [@{thm allI},@{thm impI}] 1),
-            SUBPROOF (fn {params, prems, context = ctxt', ...} =>
-              let
-                val (prems1, prems2) = chop (length prems - length rules) prems;
-                val (params1, params2) = chop (length params - length preds') params;
-              in
-                rtac (ObjectLogic.rulify (all_elims params1 (nth prems2 i))) 1 
-                THEN
-                EVERY1 (map (fn prem =>
-                  SUBPROOF (fn {prems = prems', concl, ...} =>
-                    let
-          
-                      val prem' = prems' MRS prem;
-                      val prem'' = case prop_of prem' of
-                          _ $ (Const (@{const_name All}, _) $ _) =>
-                            prem' |> all_elims params2 
-                                  |> imp_elims prems2
-                        | _ => prem';
-                    in rtac prem'' 1 end) ctxt') prems1)
-              end) ctxt 1]) |>
-      singleton (ProofContext.export lthy2 lthy1)
+  val (_, lthy2) = Variable.add_fixes parnames lthy1
+
+  fun prove_intro (i, goal) =
+    Goal.prove lthy2 [] [] goal
+        (fn {context = ctxt, ...} => 
+           EVERY1
+           [ObjectLogic.rulify_tac,
+            K (rewrite_goals_tac defs),
+            REPEAT o (resolve_tac [@{thm allI},@{thm impI}]),
+            subproof1 rules preds i ctxt])
+        |> singleton (ProofContext.export lthy2 lthy1)
 in
   map_index prove_intro rules
 end
+
 (* @end *)
 
 (* @chunk add_inductive_i *)
@@ -129,12 +165,15 @@
   val Tss = map (binder_types o fastype_of) preds';   
   val (ass,rules) = split_list specs;    
 
-  val (defs, lthy1) = definitions params' rules preds preds' Tss lthy
-  val (_, lthy2) = Variable.add_fixes (map (Binding.name_of o fst) params) lthy1;
+  val prednames = map (fst o fst) preds
+  val syns = map snd preds
+  val parnames = map (Binding.name_of o fst) params
+
+  val (defs, lthy1) = definitions rules params' preds' prednames syns Tss lthy;
       
-  val inducts = INDUCTION rules preds' Tss defs lthy1 lthy2
-
-  val intros = INTROS rules preds' defs lthy1 lthy2
+  val inducts = inductions rules defs parnames preds' Tss lthy1 	
+  
+  val intros = INTROS rules parnames preds' defs lthy1
 
   val mut_name = space_implode "_" (map (Binding.name_of o fst o fst) preds);
   val case_names = map (Binding.name_of o fst o fst) specs
Binary file cookbook.pdf has changed