src/HOL/ex/svc_funcs.ML
changeset 60332 7676bcaa1f95
parent 60331 f215fd466e30
child 60333 fd54c15231d3
--- a/src/HOL/ex/svc_funcs.ML	Mon Jun 01 15:06:09 2015 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,255 +0,0 @@
-(*  Title:      HOL/ex/svc_funcs.ML
-    Author:     Lawrence C Paulson
-    Copyright   1999  University of Cambridge
-
-Translation functions for the interface to SVC.
-
-Based upon the work of Soren 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.
-
-Relevant Isabelle environment settings:
-
-  #SVC_HOME=
-  #SVC_MACHINE=i386-redhat-linux
-  #SVC_MACHINE=sparc-sun-solaris
-*)
-
-structure Svc =
-struct
- val trace = Unsynchronized.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;
-
- 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 ^ (Library.foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ ") "
-           | ue (Interp(s, l)) =
-             "{" ^ s ^ (Library.foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ "} "
-           | ue (UnInterp(s, l)) =
-             "(" ^ s ^ (Library.foldl (fn (a, b) => a ^ " " ^ (ue b)) ("", l)) ^ ") "
-           | ue (FalseExpr) = "FALSE "
-           | ue (TrueExpr)  = "TRUE "
-           | ue (Int i)     = signed_string_of_int i ^ " "
-           | ue (Rat(i, j)) = signed_string_of_int i ^ "|" ^ signed_string_of_int 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;
-      val _ =
-        Isabelle_System.bash_output (check_valid ^ " -dump-result " ^
-          File.shell_path svc_output_file ^ " " ^ File.shell_path svc_input_file ^
-          ">/dev/null 2>&1")
-      val svc_output =
-        (case 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
-
- fun fail t = raise TERM ("SVC oracle", [t]);
-
- 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(@{const_name HOL.conj}, _)   => apply c (map tag ts)
-           | Const(@{const_name HOL.disj}, _)   => apply c (map tag ts)
-           | Const(@{const_name HOL.implies}, _) => apply c (map tag ts)
-           | Const(@{const_name Not}, _)    => apply c (map tag ts)
-           | Const(@{const_name True}, _)   => (c, false)
-           | Const(@{const_name False}, _)  => (c, false)
-           | Const(@{const_name HOL.eq}, 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(@{const_name Orderings.less}, Type ("fun", [T,_]))  => (t, is_intnat T)
-           | Const(@{const_name Orderings.less_eq}, 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 (Term.rename_wrt_term t (Term.strip_all_vars t))
-    and body   = Term.strip_all_body t
-    val nat_vars = Unsynchronized.ref ([] : string list)
-    (*translation of a variable: record all natural numbers*)
-    fun trans_var (a,T,is) =
-        (if T = HOLogic.natT then nat_vars := (insert (op =) a (!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) = 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,_) = fail t;
-    (*translation of a literal*)
-    val lit = snd o HOLogic.dest_number;
-    (*translation of a literal expression [no variables]*)
-    fun litExp (Const(@{const_name Groups.plus}, T) $ x $ y) =
-          if is_numeric_op T then (litExp x) + (litExp y)
-          else fail t
-      | litExp (Const(@{const_name Groups.minus}, T) $ x $ y) =
-          if is_numeric_op T then (litExp x) - (litExp y)
-          else fail t
-      | litExp (Const(@{const_name Groups.times}, T) $ x $ y) =
-          if is_numeric_op T then (litExp x) * (litExp y)
-          else fail t
-      | litExp (Const(@{const_name Groups.uminus}, T) $ x)   =
-          if is_numeric_op T then ~(litExp x)
-          else fail t
-      | litExp t = lit t
-                   handle Match => fail t
-    (*translation of a real/rational expression*)
-    fun suc t = Interp("+", [Int 1, t])
-    fun tm (Const(@{const_name Suc}, T) $ x) = suc (tm x)
-      | tm (Const(@{const_name Groups.plus}, T) $ x $ y) =
-          if is_numeric_op T then Interp("+", [tm x, tm y])
-          else fail t
-      | tm (Const(@{const_name Groups.minus}, T) $ x $ y) =
-          if is_numeric_op T then
-              Interp("+", [tm x, Interp("*", [Int ~1, tm y])])
-          else fail t
-      | tm (Const(@{const_name Groups.times}, T) $ x $ y) =
-          if is_numeric_op T then Interp("*", [tm x, tm y])
-          else fail t
-      | tm (Const(@{const_name Fields.inverse}, T) $ x) =
-          if domain_type T = HOLogic.realT then
-              Rat(1, litExp x)
-          else fail t
-      | tm (Const(@{const_name Groups.uminus}, T) $ x) =
-          if is_numeric_op T then Interp("*", [Int ~1, tm x])
-          else fail t
-      | tm t = Int (lit t)
-               handle Match => var (t,[])
-    (*translation of a formula*)
-    and fm pos (Const(@{const_name HOL.conj}, _) $ p $ q) =
-            Buildin("AND", [fm pos p, fm pos q])
-      | fm pos (Const(@{const_name HOL.disj}, _) $ p $ q) =
-            Buildin("OR", [fm pos p, fm pos q])
-      | fm pos (Const(@{const_name HOL.implies}, _) $ p $ q) =
-            Buildin("=>", [fm (not pos) p, fm pos q])
-      | fm pos (Const(@{const_name Not}, _) $ p) =
-            Buildin("NOT", [fm (not pos) p])
-      | fm pos (Const(@{const_name True}, _)) = TrueExpr
-      | fm pos (Const(@{const_name False}, _)) = FalseExpr
-      | fm pos (Const(@{const_name iff_keep}, _) $ p $ q) =
-             (*polarity doesn't matter*)
-            Buildin("=", [fm pos p, fm pos q])
-      | fm pos (Const(@{const_name 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(@{const_name HOL.eq}, 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 fail t
-            end
-        (*inequalities: possible types are nat, int, real*)
-      | fm pos (t as Const(@{const_name Orderings.less},  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 fail t
-      | fm pos (t as Const(@{const_name Orderings.less_eq},  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 fail t
-      | fm pos t = var(t,[]);
-      (*entry point, and translation of a meta-formula*)
-      fun mt pos ((c as Const(@{const_name Trueprop}, _)) $ p) = fm pos (iff_tag p)
-        | mt pos ((c as Const(@{const_name Pure.imp}, _)) $ 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
-     fold_rev add_nat_var (!nat_vars) body_e
-  end;
-
-
- (*The oracle proves the given formula, if possible*)
-  fun oracle ct =
-    let
-      val thy = Thm.theory_of_cterm ct;
-      val t = Thm.term_of ct;
-      val _ =
-        if ! trace then tracing ("SVC oracle: problem is\n" ^ Syntax.string_of_term_global thy t)
-       else ();
-    in if valid (expr_of false t) then ct else fail t end;
-
-end;