removed all unnecessary code
authorpaulson
Thu, 19 Aug 1999 15:13:17 +0200
changeset 7285 52ea6848b908
parent 7284 29105299799c
child 7286 fcbf147e7b4c
removed all unnecessary code
src/HOL/Tools/svc_funcs.ML
--- a/src/HOL/Tools/svc_funcs.ML	Thu Aug 19 15:12:51 1999 +0200
+++ b/src/HOL/Tools/svc_funcs.ML	Thu Aug 19 15:13:17 1999 +0200
@@ -3,7 +3,7 @@
     Author:     Lawrence C Paulson
     Copyright   1999  University of Cambridge
 
-Translation and abstraction functions for the interface to SVC
+Translation functions for the interface to SVC
 
 Based upon the work of Søren T. Heilmann
 
@@ -22,51 +22,37 @@
  val trace = ref false;
 
  datatype expr =
-     bracketed_expr of expr
-   | ref_def_expr of string * expr
-   | ref_expr of string
-   | typed_expr of Type * expr
-   | buildin_expr of string * expr list
-   | interp_expr of string * expr list
-   | uninterp_expr of string * expr list
-   | false_expr 
-   | true_expr
-   | distinct_expr of string
-   | int_expr of int
-   | rat_expr of int * int
- and Type = 
-     simple_type of string
-   | array_type of Type * Type
-   | record_type of (expr * Type) list
-   | bitvec_type of int;
+     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 signedInt i = 
-	 if i < 0 then "-" ^ Int.toString (~i)
-	 else Int.toString i
-	 fun ut(simple_type s) = s ^ " "
-	   | ut(array_type(t1, t2)) = "ARRAY " ^ (ut t1) ^ (ut t2)
-	   | ut(record_type fl) = 
-	     "RECORD" ^ 
-	     (foldl (fn (a, (d, t)) => a ^ (ue d) ^ (ut t)) (" ", fl))
-	   | ut(bitvec_type n) = "BITVEC " ^ (Int.toString n) ^ " "
-	 and ue(bracketed_expr e) = "(" ^ (ue e) ^ ") "
-	   | ue(ref_def_expr(r, e)) = "$" ^ r ^ ":" ^ (ue e)
-	   | ue(ref_expr r) = "$" ^ r ^ " "
-	   | ue(typed_expr(t, e)) = (ut t) ^ (ue e)
-	   | ue(buildin_expr(s, l)) = 
+     let fun ue (Buildin(s, l)) = 
 	     "(" ^ s ^ (foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ ") "
-	   | ue(interp_expr(s, l)) = 
+	   | ue (Interp(s, l)) = 
 	     "{" ^ s ^ (foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ "} "
-	   | ue(uninterp_expr(s, l)) = 
+	   | ue (UnInterp(s, l)) = 
 	     "(" ^ s ^ (foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ ") "
-	   | ue(false_expr) = "FALSE "
-	   | ue(true_expr) = "TRUE "
-	   | ue(distinct_expr s) = "@" ^ s ^ " "
-	   | ue(int_expr i) = (signedInt i) ^ " "
-	   | ue(rat_expr(i, j)) = (signedInt i) ^ "|" ^ (signedInt j) ^ " "
+	   | ue (FalseExpr) = "FALSE "
+	   | ue (TrueExpr)  = "TRUE "
+	   | ue (Int i)     = (signedInt i) ^ " "
+	   | ue (Rat(i, j)) = (signedInt i) ^ "|" ^ (signedInt j) ^ " "
      in
 	 ue t
      end;
@@ -91,8 +77,8 @@
       val svc_output = File.read svc_output_file
 	               handle _ => error "SVC returned no output"
   in
-      if ! trace then writeln ("SVC Returns:\n" ^ svc_output) else ();
-      if not (! trace) then (File.rm svc_input_file; File.rm svc_output_file) else ();
+      if ! trace then writeln ("SVC Returns:\n" ^ svc_output)
+      else (File.rm svc_input_file; File.rm svc_output_file);
       String.isPrefix "VALID" svc_output
   end
 
@@ -103,9 +89,7 @@
      let val (ts, bs) = ListPair.unzip args
      in  (list_comb(c,ts), exists I bs)  end;
 
- fun is_intnat T = T = HOLogic.intT orelse T = HOLogic.natT;
- 
- (*Determining whether the biconditionals must be unfoled: if there are
+ (*Determining whether the biconditionals must be unfolded: if there are
    int or nat comparisons below*)
  val iff_tag =
    let fun tag t =
@@ -128,19 +112,17 @@
 			(Const ("SVC_Oracle.iff_" ^ cname, dummyT) $ u1 $ u2,
 			 b1 orelse b2)
 		     end
-		 else (*numeric equality*)          (t, is_intnat T)
+		 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_expr("=>", [buildin_expr("<=", [int_expr 0, 
-					     uninterp_expr (a, [])]),
-			 e]);
+     Buildin("=>", [Buildin("<=", [Int 0, UnInterp (a, [])]),
+		    e]);
 
  (*Translate an Isabelle formula into an SVC expression
    pos ["positive"]: true if an assumption, false if a goal*)
@@ -153,7 +135,7 @@
     fun trans_var (a,T) =
 	(if T = HOLogic.natT then nat_vars := (a ins_string (!nat_vars))
 	                     else ();
-         uninterp_expr (a, []))
+         UnInterp (a, []))
     fun var (Free(a,T))      = trans_var ("F_" ^ a, T)
       | var (Var((a, 0), T)) = trans_var (a, T)
       | var (Bound i)        = 
@@ -167,70 +149,88 @@
       | lit (Const("RealDef.0r", _)) = 0
       | lit (Const("RealDef.1r", _)) = 1
     (*translation of a literal expression [no variables]*)
-    fun litExp (Const("op +", T) $ x $ y) = (litExp x) + (litExp y)
-      | litExp (Const("op -", T) $ x $ y) = (litExp x) - (litExp y)
-      | litExp (Const("op *", T) $ x $ y) = (litExp x) * (litExp y)
-      | litExp (Const("uminus", _) $ x)   = ~(litExp x)
+    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
+		   handle Match => raise OracleExn t
     (*translation of a real/rational expression*)
-    fun suc t = interp_expr("+", [int_expr 1, t])
+    fun suc t = Interp("+", [Int 1, t])
     fun tm (Const("Suc", T) $ x) = suc (tm x)
-      | tm (Const("op +", T) $ x $ y) = interp_expr("+", [tm x, tm y])
-      | tm (Const("op -", _) $ x $ y) = 
-	  interp_expr("+", [tm x, interp_expr("*", [int_expr ~1, tm y])])
-      | tm (Const("op *", _) $ x $ y) = interp_expr("*", [tm x, tm y])
-      | tm (Const("op /", _) $ x $ y) = 
-	  interp_expr("*", [tm x, rat_expr(1, litExp y)])
-      | tm (Const("uminus", _) $ x) = interp_expr("*", [int_expr ~1, tm x])
-      | tm t = int_expr (lit t) 
+      | 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_expr("AND", [fm pos p, fm pos q])
+	    Buildin("AND", [fm pos p, fm pos q])
       | fm pos (Const("op |", _) $ p $ q) =  
-	    buildin_expr("OR", [fm pos p, fm pos q])
+	    Buildin("OR", [fm pos p, fm pos q])
       | fm pos (Const("op -->", _) $ p $ q) =  
-	    buildin_expr("=>", [fm (not pos) p, fm pos q])
+	    Buildin("=>", [fm (not pos) p, fm pos q])
       | fm pos (Const("Not", _) $ p) =  
-	    buildin_expr("NOT", [fm (not pos) p])
-      | fm pos (Const("True", _)) = true_expr
-      | fm pos (Const("False", _)) = false_expr
+	    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_expr("=", [fm pos p, fm pos q]) 
+	    Buildin("=", [fm pos p, fm pos q]) 
       | fm pos (Const("SVC_Oracle.iff_unfold", _) $ p $ q) = 
-	    buildin_expr("AND",   (*unfolding uses both polarities*)
-			 [buildin_expr("=>", [fm (not pos) p, fm pos q]),
-			  buildin_expr("=>", [fm (not pos) q, fm pos p])])
+	    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_expr("=", [tx, ty])
+		       Buildin("=", [tx, ty])
 		   else if is_intnat T then
-		       buildin_expr("AND", 
-				    [buildin_expr("<", [tx, suc ty]), 
-				     buildin_expr("<", [ty, suc tx])])
+		       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_expr("<", [tm x, tm y])
+		Buildin("<", [tm x, tm y])
 	    else if is_intnat T then
-		buildin_expr("<=", [suc (tm x), tm y])
+		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_expr("<=", [tm x, tm y])
+		Buildin("<=", [tm x, tm y])
 	    else if is_intnat T then
-		buildin_expr("<", [tm x, suc (tm y)])
+		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_expr("=>", [mt (not pos) p, mt pos 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*)
@@ -239,89 +239,14 @@
   end;
 
 
- (*Generalize an Isabelle formula, replacing by Vars
-   all subterms not intelligible to SVC.  
-   Do not present "raw" terms to expr_of; the translation could be unsound!*)
- fun abstract t =
-  let
-    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 (op aconv) (!pairs, t) of
-		      Some v => v
-		    | None   => insert 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 ((c as Const("RealDef.0r", _))) = c
-      | rat ((c as Const("RealDef.1r", _))) = c 
-      | rat (t as Const("Numeral.number_of", _) $ w) = t
-      | rat t = replace 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 as Const("Numeral.number_of", _) $ w) = t
-      | int t = replace 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 as Const("0", _)) = t
-      | nat (t as Const("Numeral.number_of", _) $ w) = t
-      | nat t = replace 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,_])) $ x $ y) = rel (T, t)
-      | fm (t as Const("op <", Type ("fun", [T,_])) $ x $ y) = rel (T, t)
-      | fm (t as Const("op <=", Type ("fun", [T,_])) $ x $ y) = 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;
-
- (*The oracle proves not the original formula but the abstracted version*)
- fun oracle (sign, OracleExn P) = 
-   let val (absP, _) = abstract P
-       val dummy = if !trace then writeln ("Subgoal abstracted to\n" ^
-					   Sign.string_of_term sign absP)
+ (*The oracle proves the given formula t, if possible*)
+ fun oracle (sign, OracleExn t) = 
+   let val dummy = if !trace then writeln ("Subgoal abstracted to\n" ^
+					   Sign.string_of_term sign t)
                    else ()
    in
-       if valid (expr_of false absP) then absP
-       else raise OracleExn P
+       if valid (expr_of false t) then t
+       else raise OracleExn t
    end;
 
 end;