moved SVC stuff to ex;
authorwenzelm
Tue, 05 Feb 2002 23:18:08 +0100
changeset 12869 f362c0323d92
parent 12868 cdf338ef5fad
child 12870 3905bc0e9002
moved SVC stuff to ex;
src/HOL/IsaMakefile
src/HOL/PreList.thy
src/HOL/SVC_Oracle.ML
src/HOL/SVC_Oracle.thy
src/HOL/Tools/svc_funcs.ML
src/HOL/ex/ROOT.ML
src/HOL/ex/SVC_Oracle.ML
src/HOL/ex/SVC_Oracle.thy
src/HOL/ex/svc_funcs.ML
--- a/src/HOL/IsaMakefile	Tue Feb 05 15:51:28 2002 +0100
+++ b/src/HOL/IsaMakefile	Tue Feb 05 23:18:08 2002 +0100
@@ -92,15 +92,13 @@
   Option.ML Option.thy Power.ML Power.thy PreList.thy \
   Product_Type.ML Product_Type.thy ROOT.ML Recdef.thy Record.thy \
   Relation.ML Relation.thy Relation_Power.ML Relation_Power.thy \
-  SVC_Oracle.ML SVC_Oracle.thy Set.ML Set.thy SetInterval.ML \
-  SetInterval.thy Sum_Type.ML Sum_Type.thy \
+  Set.ML Set.thy SetInterval.ML SetInterval.thy Sum_Type.ML Sum_Type.thy \
   Tools/datatype_abs_proofs.ML Tools/datatype_aux.ML \
   Tools/datatype_codegen.ML Tools/datatype_package.ML Tools/datatype_prop.ML \
   Tools/datatype_rep_proofs.ML \
   Tools/inductive_package.ML Tools/inductive_codegen.ML Tools/meson.ML Tools/numeral_syntax.ML \
   Tools/primrec_package.ML Tools/recdef_package.ML Tools/recfun_codegen.ML \
-  Tools/record_package.ML Tools/split_rule.ML \
-  Tools/svc_funcs.ML Tools/typedef_package.ML \
+  Tools/record_package.ML Tools/split_rule.ML Tools/typedef_package.ML \
   Transitive_Closure.thy Transitive_Closure.ML Typedef.thy \
   Wellfounded_Recursion.ML Wellfounded_Recursion.thy Wellfounded_Relations.ML \
   Wellfounded_Relations.thy arith_data.ML blastdata.ML cladata.ML \
@@ -553,10 +551,10 @@
   ex/MT.ML ex/MT.thy ex/MonoidGroup.thy ex/Multiquote.thy \
   ex/NatSum.thy ex/PER.thy ex/Primrec.thy ex/Puzzle.ML ex/Puzzle.thy \
   ex/Qsort.ML ex/Qsort.thy ex/ROOT.ML ex/Recdefs.thy ex/Records.thy \
-  ex/Ring.ML ex/Ring.thy ex/StringEx.thy ex/Tarski.ML \
-  ex/Tarski.thy ex/Tuple.thy ex/cla.ML ex/mesontest.ML ex/mesontest2.ML \
-  ex/mesontest2.thy ex/set.ML ex/set.thy ex/svc_test.ML ex/svc_test.thy \
-  ex/document/root.bib ex/document/root.tex
+  ex/Ring.ML ex/Ring.thy ex/StringEx.thy ex/SVC_Oracle.ML ex/SVC_Oracle.thy \
+  ex/Tarski.ML ex/Tarski.thy ex/Tuple.thy ex/cla.ML ex/mesontest.ML \
+  ex/mesontest2.ML ex/mesontest2.thy ex/set.ML ex/set.thy ex/svc_funcs.ML \
+  ex/svc_test.ML ex/svc_test.thy ex/document/root.bib ex/document/root.tex
 	@$(ISATOOL) usedir $(OUT)/HOL ex
 
 
--- a/src/HOL/PreList.thy	Tue Feb 05 15:51:28 2002 +0100
+++ b/src/HOL/PreList.thy	Tue Feb 05 23:18:08 2002 +0100
@@ -9,7 +9,7 @@
 
 theory PreList =
   Option + Wellfounded_Relations + NatSimprocs + Recdef + Record +
-  Relation_Power + SVC_Oracle:
+  Relation_Power:
 
 (*belongs to theory Divides*)
 declare dvdI [intro?]  dvdE [elim?]  dvd_trans [trans]
--- a/src/HOL/SVC_Oracle.ML	Tue Feb 05 15:51:28 2002 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,113 +0,0 @@
-(*  Title:      HOL/SVC_Oracle.ML
-    ID:         $Id$
-    Author:     Lawrence C Paulson
-    Copyright   1999  University of Cambridge
-
-Installing the oracle for SVC (Stanford Validity Checker)
-
-The following code merely CALLS the oracle; 
-  the soundness-critical functions are at HOL/Tools/svc_funcs.ML
-
-Based upon the work of Søren T. Heilmann
-*)
-
-
-(*Generalize an Isabelle formula, replacing by Vars
-  all subterms not intelligible to SVC.*)
-fun svc_abstract t =
-  let
-    (*The oracle's result is given to the subgoal using compose_tac because
-      its premises are matched against the assumptions rather than used
-      to make subgoals.  Therefore , abstraction must copy the parameters
-      precisely and make them available to all generated Vars.*)
-    val params = Term.strip_all_vars t
-    and body   = Term.strip_all_body t
-    val Us = map #2 params
-    val nPar = length params
-    val vname = ref "V_a"
-    val pairs = ref ([] : (term*term) list)
-    fun insert t = 
-	let val T = fastype_of t
-            val v = Unify.combound (Var ((!vname,0), Us--->T),
-				    0, nPar)
-	in  vname := bump_string (!vname); 
-	    pairs := (t, v) :: !pairs;
-	    v
-	end;
-    fun replace t = 
-	case t of
-	    Free _  => t  (*but not existing Vars, lest the names clash*)
-	  | Bound _ => t
-	  | _ => (case gen_assoc Pattern.aeconv (!pairs, t) of
-		      Some v => v
-		    | None   => insert t)
-    (*abstraction of a numeric literal*)
-    fun lit (t as Const("0", _)) = t
-      | lit (t as Const("1", _)) = t
-      | lit (t as Const("Numeral.number_of", _) $ w) = t
-      | lit t = replace t
-    (*abstraction of a real/rational expression*)
-    fun rat ((c as Const("op +", _)) $ x $ y) = c $ (rat x) $ (rat y)
-      | rat ((c as Const("op -", _)) $ x $ y) = c $ (rat x) $ (rat y)
-      | rat ((c as Const("op /", _)) $ x $ y) = c $ (rat x) $ (rat y)
-      | rat ((c as Const("op *", _)) $ x $ y) = c $ (rat x) $ (rat y)
-      | rat ((c as Const("uminus", _)) $ x) = c $ (rat x)
-      | rat t = lit t
-    (*abstraction of an integer expression: no div, mod*)
-    fun int ((c as Const("op +", _)) $ x $ y) = c $ (int x) $ (int y)
-      | int ((c as Const("op -", _)) $ x $ y) = c $ (int x) $ (int y)
-      | int ((c as Const("op *", _)) $ x $ y) = c $ (int x) $ (int y)
-      | int ((c as Const("uminus", _)) $ x) = c $ (int x)
-      | int t = lit t
-    (*abstraction of a natural number expression: no minus*)
-    fun nat ((c as Const("op +", _)) $ x $ y) = c $ (nat x) $ (nat y)
-      | nat ((c as Const("op *", _)) $ x $ y) = c $ (nat x) $ (nat y)
-      | nat ((c as Const("Suc", _)) $ x) = c $ (nat x)
-      | nat t = lit t
-    (*abstraction of a relation: =, <, <=*)
-    fun rel (T, c $ x $ y) =
-	    if T = HOLogic.realT then c $ (rat x) $ (rat y)
-	    else if T = HOLogic.intT then c $ (int x) $ (int y)
-	    else if T = HOLogic.natT then c $ (nat x) $ (nat y)
-	    else if T = HOLogic.boolT then c $ (fm x) $ (fm y)
-	    else replace (c $ x $ y)   (*non-numeric comparison*)
-    (*abstraction of a formula*)
-    and fm ((c as Const("op &", _)) $ p $ q) = c $ (fm p) $ (fm q)
-      | fm ((c as Const("op |", _)) $ p $ q) = c $ (fm p) $ (fm q)
-      | fm ((c as Const("op -->", _)) $ p $ q) = c $ (fm p) $ (fm q)
-      | fm ((c as Const("Not", _)) $ p) = c $ (fm p)
-      | fm ((c as Const("True", _))) = c
-      | fm ((c as Const("False", _))) = c
-      | fm (t as Const("op =",  Type ("fun", [T,_])) $ _ $ _) = rel (T, t)
-      | fm (t as Const("op <",  Type ("fun", [T,_])) $ _ $ _) = rel (T, t)
-      | fm (t as Const("op <=", Type ("fun", [T,_])) $ _ $ _) = rel (T, t)
-      | fm t = replace t
-    (*entry point, and abstraction of a meta-formula*)
-    fun mt ((c as Const("Trueprop", _)) $ p) = c $ (fm p)
-      | mt ((c as Const("==>", _)) $ p $ q)  = c $ (mt p) $ (mt q)
-      | mt t = fm t  (*it might be a formula*)
-  in (list_all (params, mt body), !pairs) end;
-
-
-(*Present the entire subgoal to the oracle, assumptions and all, but possibly
-  abstracted.  Use via compose_tac, which performs no lifting but will
-  instantiate variables.*)
-local val svc_thy = the_context () in
-
-fun svc_tac i st = 
-  let val prem = BasisLibrary.List.nth (prems_of st, i-1)
-      val (absPrem, _) = svc_abstract prem
-      val th = invoke_oracle svc_thy "svc_oracle"
-	             (#sign (rep_thm st), Svc.OracleExn absPrem)
-   in 
-      compose_tac (false, th, 0) i st
-   end 
-   handle Svc.OracleExn _ => Seq.empty
-	| Subscript       => Seq.empty;
-
-end;
-
-
-(*check if user has SVC installed*)
-fun svc_enabled () = getenv "SVC_HOME" <> "";
-fun if_svc_enabled f x = if svc_enabled () then f x else ();
--- a/src/HOL/SVC_Oracle.thy	Tue Feb 05 15:51:28 2002 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,22 +0,0 @@
-(*  Title:      HOL/SVC_Oracle.thy
-    ID:         $Id$
-    Author:     Lawrence C Paulson
-    Copyright   1999  University of Cambridge
-
-Installing the oracle for SVC (Stanford Validity Checker)
-
-Based upon the work of Søren T. Heilmann
-*)
-
-theory SVC_Oracle = NatBin (** + Real??**)
-files "Tools/svc_funcs.ML":
-
-consts
-  (*reserved for the oracle*)
-  iff_keep :: "[bool, bool] => bool"
-  iff_unfold :: "[bool, bool] => bool"
-
-oracle
-  svc_oracle = Svc.oracle
-
-end
--- a/src/HOL/Tools/svc_funcs.ML	Tue Feb 05 15:51:28 2002 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,260 +0,0 @@
-(*  Title:      HOL/Tools/svc_funcs.ML
-    ID:         $Id$
-    Author:     Lawrence C Paulson
-    Copyright   1999  University of Cambridge
-
-Translation functions for the interface to SVC
-
-Based upon the work of Søren T. Heilmann
-
-Integers and naturals are translated as follows:
-  In a positive context, replace x<y by x+1<=y
-  In a negative context, replace x<=y by x<y+1
-  In a negative context, replace x=y by x<y+1 & y<x+1
-Biconditionals (if-and-only-iff) are expanded if they require such translations
-  in either operand.
-
-For each variable of type nat, an assumption is added that it is non-negative.
-*)
-
-structure Svc =
-struct
- val trace = ref false;
-
- datatype expr =
-     Buildin of string * expr list
-   | Interp of string * expr list
-   | UnInterp of string * expr list
-   | FalseExpr 
-   | TrueExpr
-   | Int of int
-   | Rat of int * int;
-
- open BasisLibrary
-
- fun signedInt i = 
-     if i < 0 then "-" ^ Int.toString (~i)
-     else Int.toString i;
-	 
- fun is_intnat T = T = HOLogic.intT orelse T = HOLogic.natT;
- 
- fun is_numeric T = is_intnat T orelse T = HOLogic.realT;
- 
- fun is_numeric_op T = is_numeric (domain_type T);
-
- fun toString t =
-     let fun ue (Buildin(s, l)) = 
-	     "(" ^ s ^ (foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ ") "
-	   | ue (Interp(s, l)) = 
-	     "{" ^ s ^ (foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ "} "
-	   | ue (UnInterp(s, l)) = 
-	     "(" ^ s ^ (foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ ") "
-	   | ue (FalseExpr) = "FALSE "
-	   | ue (TrueExpr)  = "TRUE "
-	   | ue (Int i)     = (signedInt i) ^ " "
-	   | ue (Rat(i, j)) = (signedInt i) ^ "|" ^ (signedInt j) ^ " "
-     in
-	 ue t
-     end;
-
- fun valid e = 
-  let val svc_home = getenv "SVC_HOME" 
-      val svc_machine = getenv "SVC_MACHINE"
-      val check_valid = if svc_home = ""
-	                then error "Environment variable SVC_HOME not set"
-			else if svc_machine = ""
-	                then error "Environment variable SVC_MACHINE not set"
-			else svc_home ^ "/" ^ svc_machine ^ "/bin/check_valid"
-      val svc_input = toString e
-      val _ = if !trace then tracing ("Calling SVC:\n" ^ svc_input) else ()
-      val svc_input_file  = File.tmp_path (Path.basic "SVM_in");
-      val svc_output_file = File.tmp_path (Path.basic "SVM_out");
-      val _ = (File.write svc_input_file svc_input;
-	       execute (check_valid ^ " -dump-result " ^ 
-			File.sysify_path svc_output_file ^
-			" " ^ File.sysify_path svc_input_file ^ 
-			"> /dev/null 2>&1"))
-      val svc_output =
-        (case Library.try File.read svc_output_file of
-          Some out => out
-        | None => error "SVC returned no output");
-  in
-      if ! trace then tracing ("SVC Returns:\n" ^ svc_output)
-      else (File.rm svc_input_file; File.rm svc_output_file);
-      String.isPrefix "VALID" svc_output
-  end
-
- (*New exception constructor for passing arguments to the oracle*)
- exception OracleExn of term;
-
- fun apply c args =
-     let val (ts, bs) = ListPair.unzip args
-     in  (list_comb(c,ts), exists I bs)  end;
-
- (*Determining whether the biconditionals must be unfolded: if there are
-   int or nat comparisons below*)
- val iff_tag =
-   let fun tag t =
-	 let val (c,ts) = strip_comb t
-	 in  case c of
-	     Const("op &", _)   => apply c (map tag ts)
-	   | Const("op |", _)   => apply c (map tag ts)
-	   | Const("op -->", _) => apply c (map tag ts)
-	   | Const("Not", _)    => apply c (map tag ts)
-	   | Const("True", _)   => (c, false)
-	   | Const("False", _)  => (c, false)
-	   | Const("op =", Type ("fun", [T,_])) => 
-		 if T = HOLogic.boolT then
-		     (*biconditional: with int/nat comparisons below?*)
-		     let val [t1,t2] = ts
-			 val (u1,b1) = tag t1
-			 and (u2,b2) = tag t2
-			 val cname = if b1 orelse b2 then "unfold" else "keep"
-		     in 
-			(Const ("SVC_Oracle.iff_" ^ cname, dummyT) $ u1 $ u2,
-			 b1 orelse b2)
-		     end
-		 else (*might be numeric equality*) (t, is_intnat T)
-	   | Const("op <", Type ("fun", [T,_]))  => (t, is_intnat T)
-	   | Const("op <=", Type ("fun", [T,_])) => (t, is_intnat T)
-	   | _ => (t, false)
-	 end
-   in #1 o tag end;
-
- (*Map expression e to 0<=a --> e, where "a" is the name of a nat variable*)
- fun add_nat_var (a, e) = 
-     Buildin("=>", [Buildin("<=", [Int 0, UnInterp (a, [])]),
-		    e]);
-
- fun param_string [] = ""
-   | param_string is = "_" ^ space_implode "_" (map string_of_int is)
-
- (*Translate an Isabelle formula into an SVC expression
-   pos ["positive"]: true if an assumption, false if a goal*)
- fun expr_of pos t =
-  let
-    val params = rev (rename_wrt_term t (Term.strip_all_vars t))
-    and body   = Term.strip_all_body t
-    val nat_vars = ref ([] : string list)
-    (*translation of a variable: record all natural numbers*)
-    fun trans_var (a,T,is) =
-	(if T = HOLogic.natT then nat_vars := (a ins_string (!nat_vars))
-	                     else ();
-         UnInterp (a ^ param_string is, []))
-    (*A variable, perhaps applied to a series of parameters*)
-    fun var (Free(a,T), is)      = trans_var ("F_" ^ a, T, is)
-      | var (Var((a, 0), T), is) = trans_var (a, T, is)
-      | var (Bound i, is)        = 
-          let val (a,T) = List.nth (params, i)
-	  in  trans_var ("B_" ^ a, T, is)  end
-      | var (t $ Bound i, is)    = var(t,i::is)
-            (*removing a parameter from a Var: the bound var index will
-               become part of the Var's name*)
-      | var (t,_) = raise OracleExn t;
-    (*translation of a literal*)
-    fun lit (Const("Numeral.number_of", _) $ w) =
-          (HOLogic.dest_binum w handle TERM _ => raise Match)
-      | lit (Const("0", _)) = 0
-      | lit (Const("1", _)) = 1
-    (*translation of a literal expression [no variables]*)
-    fun litExp (Const("op +", T) $ x $ y) = 
-	  if is_numeric_op T then (litExp x) + (litExp y)
-          else raise OracleExn t
-      | litExp (Const("op -", T) $ x $ y) = 
-	  if is_numeric_op T then (litExp x) - (litExp y)
-          else raise OracleExn t
-      | litExp (Const("op *", T) $ x $ y) = 
-	  if is_numeric_op T then (litExp x) * (litExp y)
-          else raise OracleExn t
-      | litExp (Const("uminus", T) $ x)   = 
-	  if is_numeric_op T then ~(litExp x)
-          else raise OracleExn t
-      | litExp t = lit t 
-		   handle Match => raise OracleExn t
-    (*translation of a real/rational expression*)
-    fun suc t = Interp("+", [Int 1, t])
-    fun tm (Const("Suc", T) $ x) = suc (tm x)
-      | tm (Const("op +", T) $ x $ y) = 
-	  if is_numeric_op T then Interp("+", [tm x, tm y])
-          else raise OracleExn t
-      | tm (Const("op -", T) $ x $ y) = 
-	  if is_numeric_op T then 
-	      Interp("+", [tm x, Interp("*", [Int ~1, tm y])])
-          else raise OracleExn t
-      | tm (Const("op *", T) $ x $ y) = 
-	  if is_numeric_op T then Interp("*", [tm x, tm y])
-          else raise OracleExn t
-      | tm (Const("RealDef.rinv", T) $ x) = 
-	  if domain_type T = HOLogic.realT then 
-	      Rat(1, litExp x)
-          else raise OracleExn t
-      | tm (Const("uminus", T) $ x) = 
-	  if is_numeric_op T then Interp("*", [Int ~1, tm x])
-          else raise OracleExn t
-      | tm t = Int (lit t) 
-	       handle Match => var (t,[])
-    (*translation of a formula*)
-    and fm pos (Const("op &", _) $ p $ q) =  
-	    Buildin("AND", [fm pos p, fm pos q])
-      | fm pos (Const("op |", _) $ p $ q) =  
-	    Buildin("OR", [fm pos p, fm pos q])
-      | fm pos (Const("op -->", _) $ p $ q) =  
-	    Buildin("=>", [fm (not pos) p, fm pos q])
-      | fm pos (Const("Not", _) $ p) =  
-	    Buildin("NOT", [fm (not pos) p])
-      | fm pos (Const("True", _)) = TrueExpr
-      | fm pos (Const("False", _)) = FalseExpr
-      | fm pos (Const("SVC_Oracle.iff_keep", _) $ p $ q) = 
-	     (*polarity doesn't matter*)
-	    Buildin("=", [fm pos p, fm pos q]) 
-      | fm pos (Const("SVC_Oracle.iff_unfold", _) $ p $ q) = 
-	    Buildin("AND",   (*unfolding uses both polarities*)
-			 [Buildin("=>", [fm (not pos) p, fm pos q]),
-			  Buildin("=>", [fm (not pos) q, fm pos p])])
-      | fm pos (t as Const("op =", Type ("fun", [T,_])) $ x $ y) = 
-	    let val tx = tm x and ty = tm y
-		in if pos orelse T = HOLogic.realT then
-		       Buildin("=", [tx, ty])
-		   else if is_intnat T then
-		       Buildin("AND", 
-				    [Buildin("<", [tx, suc ty]), 
-				     Buildin("<", [ty, suc tx])])
-		   else raise OracleExn t
-	    end
-	(*inequalities: possible types are nat, int, real*)
-      | fm pos (t as Const("op <",  Type ("fun", [T,_])) $ x $ y) = 
-	    if not pos orelse T = HOLogic.realT then
-		Buildin("<", [tm x, tm y])
-	    else if is_intnat T then
-		Buildin("<=", [suc (tm x), tm y])
-	    else raise OracleExn t
-      | fm pos (t as Const("op <=",  Type ("fun", [T,_])) $ x $ y) = 
-	    if pos orelse T = HOLogic.realT then
-		Buildin("<=", [tm x, tm y])
-	    else if is_intnat T then
-		Buildin("<", [tm x, suc (tm y)])
-	    else raise OracleExn t
-      | fm pos t = var(t,[]);
-      (*entry point, and translation of a meta-formula*)
-      fun mt pos ((c as Const("Trueprop", _)) $ p) = fm pos (iff_tag p)
-	| mt pos ((c as Const("==>", _)) $ p $ q) = 
-	    Buildin("=>", [mt (not pos) p, mt pos q])
-	| mt pos t = fm pos (iff_tag t)  (*it might be a formula*)
-
-      val body_e = mt pos body  (*evaluate now to assign into !nat_vars*)
-  in 
-     foldr add_nat_var (!nat_vars, body_e) 
-  end;
-
-
- (*The oracle proves the given formula t, if possible*)
- fun oracle (sign, OracleExn t) = 
-   let val dummy = if !trace then tracing ("Subgoal abstracted to\n" ^
-					   Sign.string_of_term sign t)
-                   else ()
-   in
-       if valid (expr_of false t) then t
-       else raise OracleExn t
-   end;
-
-end;
--- a/src/HOL/ex/ROOT.ML	Tue Feb 05 15:51:28 2002 +0100
+++ b/src/HOL/ex/ROOT.ML	Tue Feb 05 23:18:08 2002 +0100
@@ -35,4 +35,5 @@
 time_use_thy "MT";
 time_use_thy "Tarski";
 
+time_use_thy "SVC_Oracle";
 if_svc_enabled time_use_thy "svc_test";
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/ex/SVC_Oracle.ML	Tue Feb 05 23:18:08 2002 +0100
@@ -0,0 +1,113 @@
+(*  Title:      HOL/SVC_Oracle.ML
+    ID:         $Id$
+    Author:     Lawrence C Paulson
+    Copyright   1999  University of Cambridge
+
+Installing the oracle for SVC (Stanford Validity Checker)
+
+The following code merely CALLS the oracle; 
+  the soundness-critical functions are at HOL/Tools/svc_funcs.ML
+
+Based upon the work of Søren T. Heilmann
+*)
+
+
+(*Generalize an Isabelle formula, replacing by Vars
+  all subterms not intelligible to SVC.*)
+fun svc_abstract t =
+  let
+    (*The oracle's result is given to the subgoal using compose_tac because
+      its premises are matched against the assumptions rather than used
+      to make subgoals.  Therefore , abstraction must copy the parameters
+      precisely and make them available to all generated Vars.*)
+    val params = Term.strip_all_vars t
+    and body   = Term.strip_all_body t
+    val Us = map #2 params
+    val nPar = length params
+    val vname = ref "V_a"
+    val pairs = ref ([] : (term*term) list)
+    fun insert t = 
+	let val T = fastype_of t
+            val v = Unify.combound (Var ((!vname,0), Us--->T),
+				    0, nPar)
+	in  vname := bump_string (!vname); 
+	    pairs := (t, v) :: !pairs;
+	    v
+	end;
+    fun replace t = 
+	case t of
+	    Free _  => t  (*but not existing Vars, lest the names clash*)
+	  | Bound _ => t
+	  | _ => (case gen_assoc Pattern.aeconv (!pairs, t) of
+		      Some v => v
+		    | None   => insert t)
+    (*abstraction of a numeric literal*)
+    fun lit (t as Const("0", _)) = t
+      | lit (t as Const("1", _)) = t
+      | lit (t as Const("Numeral.number_of", _) $ w) = t
+      | lit t = replace t
+    (*abstraction of a real/rational expression*)
+    fun rat ((c as Const("op +", _)) $ x $ y) = c $ (rat x) $ (rat y)
+      | rat ((c as Const("op -", _)) $ x $ y) = c $ (rat x) $ (rat y)
+      | rat ((c as Const("op /", _)) $ x $ y) = c $ (rat x) $ (rat y)
+      | rat ((c as Const("op *", _)) $ x $ y) = c $ (rat x) $ (rat y)
+      | rat ((c as Const("uminus", _)) $ x) = c $ (rat x)
+      | rat t = lit t
+    (*abstraction of an integer expression: no div, mod*)
+    fun int ((c as Const("op +", _)) $ x $ y) = c $ (int x) $ (int y)
+      | int ((c as Const("op -", _)) $ x $ y) = c $ (int x) $ (int y)
+      | int ((c as Const("op *", _)) $ x $ y) = c $ (int x) $ (int y)
+      | int ((c as Const("uminus", _)) $ x) = c $ (int x)
+      | int t = lit t
+    (*abstraction of a natural number expression: no minus*)
+    fun nat ((c as Const("op +", _)) $ x $ y) = c $ (nat x) $ (nat y)
+      | nat ((c as Const("op *", _)) $ x $ y) = c $ (nat x) $ (nat y)
+      | nat ((c as Const("Suc", _)) $ x) = c $ (nat x)
+      | nat t = lit t
+    (*abstraction of a relation: =, <, <=*)
+    fun rel (T, c $ x $ y) =
+	    if T = HOLogic.realT then c $ (rat x) $ (rat y)
+	    else if T = HOLogic.intT then c $ (int x) $ (int y)
+	    else if T = HOLogic.natT then c $ (nat x) $ (nat y)
+	    else if T = HOLogic.boolT then c $ (fm x) $ (fm y)
+	    else replace (c $ x $ y)   (*non-numeric comparison*)
+    (*abstraction of a formula*)
+    and fm ((c as Const("op &", _)) $ p $ q) = c $ (fm p) $ (fm q)
+      | fm ((c as Const("op |", _)) $ p $ q) = c $ (fm p) $ (fm q)
+      | fm ((c as Const("op -->", _)) $ p $ q) = c $ (fm p) $ (fm q)
+      | fm ((c as Const("Not", _)) $ p) = c $ (fm p)
+      | fm ((c as Const("True", _))) = c
+      | fm ((c as Const("False", _))) = c
+      | fm (t as Const("op =",  Type ("fun", [T,_])) $ _ $ _) = rel (T, t)
+      | fm (t as Const("op <",  Type ("fun", [T,_])) $ _ $ _) = rel (T, t)
+      | fm (t as Const("op <=", Type ("fun", [T,_])) $ _ $ _) = rel (T, t)
+      | fm t = replace t
+    (*entry point, and abstraction of a meta-formula*)
+    fun mt ((c as Const("Trueprop", _)) $ p) = c $ (fm p)
+      | mt ((c as Const("==>", _)) $ p $ q)  = c $ (mt p) $ (mt q)
+      | mt t = fm t  (*it might be a formula*)
+  in (list_all (params, mt body), !pairs) end;
+
+
+(*Present the entire subgoal to the oracle, assumptions and all, but possibly
+  abstracted.  Use via compose_tac, which performs no lifting but will
+  instantiate variables.*)
+local val svc_thy = the_context () in
+
+fun svc_tac i st = 
+  let val prem = BasisLibrary.List.nth (prems_of st, i-1)
+      val (absPrem, _) = svc_abstract prem
+      val th = invoke_oracle svc_thy "svc_oracle"
+	             (#sign (rep_thm st), Svc.OracleExn absPrem)
+   in 
+      compose_tac (false, th, 0) i st
+   end 
+   handle Svc.OracleExn _ => Seq.empty
+	| Subscript       => Seq.empty;
+
+end;
+
+
+(*check if user has SVC installed*)
+fun svc_enabled () = getenv "SVC_HOME" <> "";
+fun if_svc_enabled f x = if svc_enabled () then f x else ();
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/ex/SVC_Oracle.thy	Tue Feb 05 23:18:08 2002 +0100
@@ -0,0 +1,22 @@
+(*  Title:      HOL/ex/SVC_Oracle.thy
+    ID:         $Id$
+    Author:     Lawrence C Paulson
+    Copyright   1999  University of Cambridge
+
+Installing the oracle for SVC (Stanford Validity Checker)
+
+Based upon the work of Søren T. Heilmann
+*)
+
+theory SVC_Oracle = Main (** + Real??**)
+files "svc_funcs.ML":
+
+consts
+  (*reserved for the oracle*)
+  iff_keep :: "[bool, bool] => bool"
+  iff_unfold :: "[bool, bool] => bool"
+
+oracle
+  svc_oracle = Svc.oracle
+
+end
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/ex/svc_funcs.ML	Tue Feb 05 23:18:08 2002 +0100
@@ -0,0 +1,260 @@
+(*  Title:      HOL/Tools/svc_funcs.ML
+    ID:         $Id$
+    Author:     Lawrence C Paulson
+    Copyright   1999  University of Cambridge
+
+Translation functions for the interface to SVC
+
+Based upon the work of Søren T. Heilmann
+
+Integers and naturals are translated as follows:
+  In a positive context, replace x<y by x+1<=y
+  In a negative context, replace x<=y by x<y+1
+  In a negative context, replace x=y by x<y+1 & y<x+1
+Biconditionals (if-and-only-iff) are expanded if they require such translations
+  in either operand.
+
+For each variable of type nat, an assumption is added that it is non-negative.
+*)
+
+structure Svc =
+struct
+ val trace = ref false;
+
+ datatype expr =
+     Buildin of string * expr list
+   | Interp of string * expr list
+   | UnInterp of string * expr list
+   | FalseExpr 
+   | TrueExpr
+   | Int of int
+   | Rat of int * int;
+
+ open BasisLibrary
+
+ fun signedInt i = 
+     if i < 0 then "-" ^ Int.toString (~i)
+     else Int.toString i;
+	 
+ fun is_intnat T = T = HOLogic.intT orelse T = HOLogic.natT;
+ 
+ fun is_numeric T = is_intnat T orelse T = HOLogic.realT;
+ 
+ fun is_numeric_op T = is_numeric (domain_type T);
+
+ fun toString t =
+     let fun ue (Buildin(s, l)) = 
+	     "(" ^ s ^ (foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ ") "
+	   | ue (Interp(s, l)) = 
+	     "{" ^ s ^ (foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ "} "
+	   | ue (UnInterp(s, l)) = 
+	     "(" ^ s ^ (foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ ") "
+	   | ue (FalseExpr) = "FALSE "
+	   | ue (TrueExpr)  = "TRUE "
+	   | ue (Int i)     = (signedInt i) ^ " "
+	   | ue (Rat(i, j)) = (signedInt i) ^ "|" ^ (signedInt j) ^ " "
+     in
+	 ue t
+     end;
+
+ fun valid e = 
+  let val svc_home = getenv "SVC_HOME" 
+      val svc_machine = getenv "SVC_MACHINE"
+      val check_valid = if svc_home = ""
+	                then error "Environment variable SVC_HOME not set"
+			else if svc_machine = ""
+	                then error "Environment variable SVC_MACHINE not set"
+			else svc_home ^ "/" ^ svc_machine ^ "/bin/check_valid"
+      val svc_input = toString e
+      val _ = if !trace then tracing ("Calling SVC:\n" ^ svc_input) else ()
+      val svc_input_file  = File.tmp_path (Path.basic "SVM_in");
+      val svc_output_file = File.tmp_path (Path.basic "SVM_out");
+      val _ = (File.write svc_input_file svc_input;
+	       execute (check_valid ^ " -dump-result " ^ 
+			File.sysify_path svc_output_file ^
+			" " ^ File.sysify_path svc_input_file ^ 
+			"> /dev/null 2>&1"))
+      val svc_output =
+        (case Library.try File.read svc_output_file of
+          Some out => out
+        | None => error "SVC returned no output");
+  in
+      if ! trace then tracing ("SVC Returns:\n" ^ svc_output)
+      else (File.rm svc_input_file; File.rm svc_output_file);
+      String.isPrefix "VALID" svc_output
+  end
+
+ (*New exception constructor for passing arguments to the oracle*)
+ exception OracleExn of term;
+
+ fun apply c args =
+     let val (ts, bs) = ListPair.unzip args
+     in  (list_comb(c,ts), exists I bs)  end;
+
+ (*Determining whether the biconditionals must be unfolded: if there are
+   int or nat comparisons below*)
+ val iff_tag =
+   let fun tag t =
+	 let val (c,ts) = strip_comb t
+	 in  case c of
+	     Const("op &", _)   => apply c (map tag ts)
+	   | Const("op |", _)   => apply c (map tag ts)
+	   | Const("op -->", _) => apply c (map tag ts)
+	   | Const("Not", _)    => apply c (map tag ts)
+	   | Const("True", _)   => (c, false)
+	   | Const("False", _)  => (c, false)
+	   | Const("op =", Type ("fun", [T,_])) => 
+		 if T = HOLogic.boolT then
+		     (*biconditional: with int/nat comparisons below?*)
+		     let val [t1,t2] = ts
+			 val (u1,b1) = tag t1
+			 and (u2,b2) = tag t2
+			 val cname = if b1 orelse b2 then "unfold" else "keep"
+		     in 
+			(Const ("SVC_Oracle.iff_" ^ cname, dummyT) $ u1 $ u2,
+			 b1 orelse b2)
+		     end
+		 else (*might be numeric equality*) (t, is_intnat T)
+	   | Const("op <", Type ("fun", [T,_]))  => (t, is_intnat T)
+	   | Const("op <=", Type ("fun", [T,_])) => (t, is_intnat T)
+	   | _ => (t, false)
+	 end
+   in #1 o tag end;
+
+ (*Map expression e to 0<=a --> e, where "a" is the name of a nat variable*)
+ fun add_nat_var (a, e) = 
+     Buildin("=>", [Buildin("<=", [Int 0, UnInterp (a, [])]),
+		    e]);
+
+ fun param_string [] = ""
+   | param_string is = "_" ^ space_implode "_" (map string_of_int is)
+
+ (*Translate an Isabelle formula into an SVC expression
+   pos ["positive"]: true if an assumption, false if a goal*)
+ fun expr_of pos t =
+  let
+    val params = rev (rename_wrt_term t (Term.strip_all_vars t))
+    and body   = Term.strip_all_body t
+    val nat_vars = ref ([] : string list)
+    (*translation of a variable: record all natural numbers*)
+    fun trans_var (a,T,is) =
+	(if T = HOLogic.natT then nat_vars := (a ins_string (!nat_vars))
+	                     else ();
+         UnInterp (a ^ param_string is, []))
+    (*A variable, perhaps applied to a series of parameters*)
+    fun var (Free(a,T), is)      = trans_var ("F_" ^ a, T, is)
+      | var (Var((a, 0), T), is) = trans_var (a, T, is)
+      | var (Bound i, is)        = 
+          let val (a,T) = List.nth (params, i)
+	  in  trans_var ("B_" ^ a, T, is)  end
+      | var (t $ Bound i, is)    = var(t,i::is)
+            (*removing a parameter from a Var: the bound var index will
+               become part of the Var's name*)
+      | var (t,_) = raise OracleExn t;
+    (*translation of a literal*)
+    fun lit (Const("Numeral.number_of", _) $ w) =
+          (HOLogic.dest_binum w handle TERM _ => raise Match)
+      | lit (Const("0", _)) = 0
+      | lit (Const("1", _)) = 1
+    (*translation of a literal expression [no variables]*)
+    fun litExp (Const("op +", T) $ x $ y) = 
+	  if is_numeric_op T then (litExp x) + (litExp y)
+          else raise OracleExn t
+      | litExp (Const("op -", T) $ x $ y) = 
+	  if is_numeric_op T then (litExp x) - (litExp y)
+          else raise OracleExn t
+      | litExp (Const("op *", T) $ x $ y) = 
+	  if is_numeric_op T then (litExp x) * (litExp y)
+          else raise OracleExn t
+      | litExp (Const("uminus", T) $ x)   = 
+	  if is_numeric_op T then ~(litExp x)
+          else raise OracleExn t
+      | litExp t = lit t 
+		   handle Match => raise OracleExn t
+    (*translation of a real/rational expression*)
+    fun suc t = Interp("+", [Int 1, t])
+    fun tm (Const("Suc", T) $ x) = suc (tm x)
+      | tm (Const("op +", T) $ x $ y) = 
+	  if is_numeric_op T then Interp("+", [tm x, tm y])
+          else raise OracleExn t
+      | tm (Const("op -", T) $ x $ y) = 
+	  if is_numeric_op T then 
+	      Interp("+", [tm x, Interp("*", [Int ~1, tm y])])
+          else raise OracleExn t
+      | tm (Const("op *", T) $ x $ y) = 
+	  if is_numeric_op T then Interp("*", [tm x, tm y])
+          else raise OracleExn t
+      | tm (Const("RealDef.rinv", T) $ x) = 
+	  if domain_type T = HOLogic.realT then 
+	      Rat(1, litExp x)
+          else raise OracleExn t
+      | tm (Const("uminus", T) $ x) = 
+	  if is_numeric_op T then Interp("*", [Int ~1, tm x])
+          else raise OracleExn t
+      | tm t = Int (lit t) 
+	       handle Match => var (t,[])
+    (*translation of a formula*)
+    and fm pos (Const("op &", _) $ p $ q) =  
+	    Buildin("AND", [fm pos p, fm pos q])
+      | fm pos (Const("op |", _) $ p $ q) =  
+	    Buildin("OR", [fm pos p, fm pos q])
+      | fm pos (Const("op -->", _) $ p $ q) =  
+	    Buildin("=>", [fm (not pos) p, fm pos q])
+      | fm pos (Const("Not", _) $ p) =  
+	    Buildin("NOT", [fm (not pos) p])
+      | fm pos (Const("True", _)) = TrueExpr
+      | fm pos (Const("False", _)) = FalseExpr
+      | fm pos (Const("SVC_Oracle.iff_keep", _) $ p $ q) = 
+	     (*polarity doesn't matter*)
+	    Buildin("=", [fm pos p, fm pos q]) 
+      | fm pos (Const("SVC_Oracle.iff_unfold", _) $ p $ q) = 
+	    Buildin("AND",   (*unfolding uses both polarities*)
+			 [Buildin("=>", [fm (not pos) p, fm pos q]),
+			  Buildin("=>", [fm (not pos) q, fm pos p])])
+      | fm pos (t as Const("op =", Type ("fun", [T,_])) $ x $ y) = 
+	    let val tx = tm x and ty = tm y
+		in if pos orelse T = HOLogic.realT then
+		       Buildin("=", [tx, ty])
+		   else if is_intnat T then
+		       Buildin("AND", 
+				    [Buildin("<", [tx, suc ty]), 
+				     Buildin("<", [ty, suc tx])])
+		   else raise OracleExn t
+	    end
+	(*inequalities: possible types are nat, int, real*)
+      | fm pos (t as Const("op <",  Type ("fun", [T,_])) $ x $ y) = 
+	    if not pos orelse T = HOLogic.realT then
+		Buildin("<", [tm x, tm y])
+	    else if is_intnat T then
+		Buildin("<=", [suc (tm x), tm y])
+	    else raise OracleExn t
+      | fm pos (t as Const("op <=",  Type ("fun", [T,_])) $ x $ y) = 
+	    if pos orelse T = HOLogic.realT then
+		Buildin("<=", [tm x, tm y])
+	    else if is_intnat T then
+		Buildin("<", [tm x, suc (tm y)])
+	    else raise OracleExn t
+      | fm pos t = var(t,[]);
+      (*entry point, and translation of a meta-formula*)
+      fun mt pos ((c as Const("Trueprop", _)) $ p) = fm pos (iff_tag p)
+	| mt pos ((c as Const("==>", _)) $ p $ q) = 
+	    Buildin("=>", [mt (not pos) p, mt pos q])
+	| mt pos t = fm pos (iff_tag t)  (*it might be a formula*)
+
+      val body_e = mt pos body  (*evaluate now to assign into !nat_vars*)
+  in 
+     foldr add_nat_var (!nat_vars, body_e) 
+  end;
+
+
+ (*The oracle proves the given formula t, if possible*)
+ fun oracle (sign, OracleExn t) = 
+   let val dummy = if !trace then tracing ("Subgoal abstracted to\n" ^
+					   Sign.string_of_term sign t)
+                   else ()
+   in
+       if valid (expr_of false t) then t
+       else raise OracleExn t
+   end;
+
+end;