# HG changeset patch
# User blanchet
# Date 1280495022 -7200
# Node ID d44a5f602b8c893bede0c002394c71542b98b74f
# Parent  61280b97b7612cea8bd63ed1408978f7fa9176ee# Parent  373351f5f834b97bf12a625665f8be2efb48842e
merged

diff -r 373351f5f834 -r d44a5f602b8c src/HOL/Imperative_HOL/Ref.thy
--- a/src/HOL/Imperative_HOL/Ref.thy	Fri Jul 30 00:02:25 2010 +0200
+++ b/src/HOL/Imperative_HOL/Ref.thy	Fri Jul 30 15:03:42 2010 +0200
@@ -263,22 +263,32 @@
 
 subsection {* Code generator setup *}
 
+text {* Intermediate operation avoids invariance problem in @{text Scala} (similiar to value restriction) *}
+
+definition ref' where
+  [code del]: "ref' = ref"
+
+lemma [code]:
+  "ref x = ref' x"
+  by (simp add: ref'_def)
+
+
 text {* SML *}
 
 code_type ref (SML "_/ Unsynchronized.ref")
 code_const Ref (SML "raise/ (Fail/ \"bare Ref\")")
-code_const ref (SML "(fn/ ()/ =>/ Unsynchronized.ref/ _)")
+code_const ref' (SML "(fn/ ()/ =>/ Unsynchronized.ref/ _)")
 code_const Ref.lookup (SML "(fn/ ()/ =>/ !/ _)")
 code_const Ref.update (SML "(fn/ ()/ =>/ _/ :=/ _)")
 
-code_reserved SML ref
+code_reserved SML Unsynchronized
 
 
 text {* OCaml *}
 
 code_type ref (OCaml "_/ ref")
 code_const Ref (OCaml "failwith/ \"bare Ref\"")
-code_const ref (OCaml "(fun/ ()/ ->/ ref/ _)")
+code_const ref' (OCaml "(fun/ ()/ ->/ ref/ _)")
 code_const Ref.lookup (OCaml "(fun/ ()/ ->/ !/ _)")
 code_const Ref.update (OCaml "(fun/ ()/ ->/ _/ :=/ _)")
 
@@ -289,7 +299,7 @@
 
 code_type ref (Haskell "Heap.STRef/ Heap.RealWorld/ _")
 code_const Ref (Haskell "error/ \"bare Ref\"")
-code_const ref (Haskell "Heap.newSTRef")
+code_const ref' (Haskell "Heap.newSTRef")
 code_const Ref.lookup (Haskell "Heap.readSTRef")
 code_const Ref.update (Haskell "Heap.writeSTRef")
 
@@ -298,7 +308,7 @@
 
 code_type ref (Scala "!Ref[_]")
 code_const Ref (Scala "!error(\"bare Ref\")")
-code_const ref (Scala "('_: Unit)/ =>/ Ref((_))")
+code_const ref' (Scala "('_: Unit)/ =>/ Ref((_))")
 code_const Ref.lookup (Scala "('_: Unit)/ =>/ Ref.lookup((_))")
 code_const Ref.update (Scala "('_: Unit)/ =>/ Ref.update((_), (_))")
 
diff -r 373351f5f834 -r d44a5f602b8c src/HOL/Imperative_HOL/ex/Imperative_Reverse.thy
--- a/src/HOL/Imperative_HOL/ex/Imperative_Reverse.thy	Fri Jul 30 00:02:25 2010 +0200
+++ b/src/HOL/Imperative_HOL/ex/Imperative_Reverse.thy	Fri Jul 30 15:03:42 2010 +0200
@@ -110,7 +110,7 @@
       subarray_def sublist'_all rev.simps[where j=0] elim!: crel_elims)
   (drule sym[of "List.length (Array.get h a)"], simp)
 
-definition "example = (Array.of_list [1::nat, 2, 3, 4, 5, 6, 7, 8, 9, 10] \<guillemotright>= (\<lambda>a. rev a 0 9))"
+definition "example = (Array.make 10 id \<guillemotright>= (\<lambda>a. rev a 0 9))"
 
 export_code example checking SML SML_imp OCaml? OCaml_imp? Haskell? Scala? Scala_imp?
 
diff -r 373351f5f834 -r d44a5f602b8c src/HOL/Imperative_HOL/ex/Linked_Lists.thy
--- a/src/HOL/Imperative_HOL/ex/Linked_Lists.thy	Fri Jul 30 00:02:25 2010 +0200
+++ b/src/HOL/Imperative_HOL/ex/Linked_Lists.thy	Fri Jul 30 15:03:42 2010 +0200
@@ -1014,6 +1014,6 @@
 ML {* @{code test_2} () *}
 ML {* @{code test_3} () *}
 
-export_code test_1 test_2 test_3 checking SML SML_imp OCaml? OCaml_imp? Haskell? Scala? (*Scala_imp?*)
+export_code test_1 test_2 test_3 checking SML SML_imp OCaml? OCaml_imp? Haskell? Scala? Scala_imp?
 
 end
diff -r 373351f5f834 -r d44a5f602b8c src/HOL/IsaMakefile
--- a/src/HOL/IsaMakefile	Fri Jul 30 00:02:25 2010 +0200
+++ b/src/HOL/IsaMakefile	Fri Jul 30 15:03:42 2010 +0200
@@ -1320,7 +1320,8 @@
 $(LOG)/HOL-Predicate_Compile_Examples.gz: $(OUT)/HOL			\
   Predicate_Compile_Examples/ROOT.ML					\
   Predicate_Compile_Examples/Predicate_Compile_Examples.thy		\
-  Predicate_Compile_Examples/Predicate_Compile_Quickcheck_Examples.thy
+  Predicate_Compile_Examples/Predicate_Compile_Quickcheck_Examples.thy  \
+  Predicate_Compile_Examples/Code_Prolog_Examples.thy
 	@$(ISABELLE_TOOL) usedir $(OUT)/HOL Predicate_Compile_Examples
 
 
diff -r 373351f5f834 -r d44a5f602b8c src/HOL/Predicate_Compile_Examples/Code_Prolog_Examples.thy
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/Predicate_Compile_Examples/Code_Prolog_Examples.thy	Fri Jul 30 15:03:42 2010 +0200
@@ -0,0 +1,17 @@
+theory Code_Prolog_Examples
+imports Predicate_Compile_Alternative_Defs
+uses "~~/src/HOL/Tools/Predicate_Compile/code_prolog.ML"
+begin
+
+section {* Example append *}
+
+inductive append
+where
+  "append [] ys ys"
+| "append xs ys zs ==> append (x # xs) ys (x # zs)"
+
+code_pred append .
+
+values 3 "{((x::'b list), y, z). append x y z}"
+
+end
diff -r 373351f5f834 -r d44a5f602b8c src/HOL/Tools/Predicate_Compile/code_prolog.ML
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/Tools/Predicate_Compile/code_prolog.ML	Fri Jul 30 15:03:42 2010 +0200
@@ -0,0 +1,337 @@
+(*  Title:      HOL/Tools/Predicate_Compile/code_prolog.ML
+    Author:     Lukas Bulwahn, TU Muenchen
+
+Prototype of an code generator for logic programming languages (a.k.a. Prolog)
+*)
+
+signature CODE_PROLOG =
+sig
+  datatype prol_term = Var of string | Cons of string | AppF of string * prol_term list;
+  datatype prem = Conj of prem list | NotRel of string * prol_term list
+    | Rel of string * prol_term list | Eq of prol_term * prol_term | NotEq of prol_term * prol_term;
+  type clause = ((string * prol_term list) * prem);
+  type logic_program = clause list;
+  type constant_table = (string * string) list
+  
+  val generate : Proof.context -> string list -> (logic_program * constant_table)
+  val write_program : logic_program -> string
+  val run : logic_program -> string -> string list -> int option -> prol_term list list
+
+  val trace : bool Unsynchronized.ref
+end;
+
+structure Code_Prolog : CODE_PROLOG =
+struct
+
+(* diagnostic tracing *)
+
+val trace = Unsynchronized.ref false
+
+fun tracing s = if !trace then Output.tracing s else () 
+(* general string functions *)
+
+val first_upper = implode o nth_map 0 Symbol.to_ascii_upper o explode;
+val first_lower = implode o nth_map 0 Symbol.to_ascii_lower o explode;
+
+(* internal program representation *)
+
+datatype prol_term = Var of string | Cons of string | AppF of string * prol_term list;
+
+fun string_of_prol_term (Var s) = "Var " ^ s
+  | string_of_prol_term (Cons s) = "Cons " ^ s
+  | string_of_prol_term (AppF (f, args)) = f ^ "(" ^ commas (map string_of_prol_term args) ^ ")" 
+
+datatype prem = Conj of prem list | NotRel of string * prol_term list
+    | Rel of string * prol_term list | Eq of prol_term * prol_term | NotEq of prol_term * prol_term;
+
+fun dest_Rel (Rel (c, ts)) = (c, ts)
+ 
+type clause = ((string * prol_term list) * prem);
+
+type logic_program = clause list;
+
+(* translation from introduction rules to internal representation *)
+
+(** constant table **)
+
+type constant_table = (string * string) list
+
+(* assuming no clashing *)
+fun mk_constant_table consts =
+  AList.make (first_lower o Long_Name.base_name) consts
+
+fun declare_consts consts constant_table =
+  fold (fn c => AList.update (op =) (c, first_lower (Long_Name.base_name c))) consts constant_table
+  
+fun translate_const constant_table c =
+  case AList.lookup (op =) constant_table c of
+    SOME c' => c'
+  | NONE => error ("No such constant: " ^ c)
+
+fun inv_lookup _ [] _ = NONE
+  | inv_lookup eq ((key, value)::xs) value' =
+      if eq (value', value) then SOME key
+      else inv_lookup eq xs value';
+
+fun restore_const constant_table c =
+  case inv_lookup (op =) constant_table c of
+    SOME c' => c'
+  | NONE => error ("No constant corresponding to "  ^ c)
+  
+(** translation of terms, literals, premises, and clauses **)
+
+fun translate_term ctxt constant_table t =
+  case strip_comb t of
+    (Free (v, T), []) => Var v 
+  | (Const (c, _), []) => Cons (translate_const constant_table c)
+  | (Const (c, _), args) =>
+    AppF (translate_const constant_table c, map (translate_term ctxt constant_table) args)
+  | _ => error ("illegal term for translation: " ^ Syntax.string_of_term ctxt t)
+
+fun translate_literal ctxt constant_table t =
+  case strip_comb t of
+    (Const (@{const_name "op ="}, _), [l, r]) =>
+      Eq (pairself (translate_term ctxt constant_table) (l, r))
+  | (Const (c, _), args) =>
+      Rel (translate_const constant_table c, map (translate_term ctxt constant_table) args)
+  | _ => error ("illegal literal for translation: " ^ Syntax.string_of_term ctxt t)
+
+fun NegRel_of (Rel lit) = NotRel lit
+  | NegRel_of (Eq eq) = NotEq eq
+  
+fun translate_prem ctxt constant_table t =  
+    case try HOLogic.dest_not t of
+      SOME t => NegRel_of (translate_literal ctxt constant_table t)
+    | NONE => translate_literal ctxt constant_table t
+
+fun translate_intros ctxt gr const constant_table =
+  let
+    val intros = Graph.get_node gr const
+    val (intros', ctxt') = Variable.import_terms true (map prop_of intros) ctxt
+    val constant_table' = declare_consts (fold Term.add_const_names intros' []) constant_table
+    fun translate_intro intro =
+      let
+        val head = HOLogic.dest_Trueprop (Logic.strip_imp_concl intro)
+        val prems = map HOLogic.dest_Trueprop (Logic.strip_imp_prems intro) 
+        val prems' = Conj (map (translate_prem ctxt' constant_table') prems)
+        val clause = (dest_Rel (translate_literal ctxt' constant_table' head), prems')
+      in clause end
+  in (map translate_intro intros', constant_table') end
+
+fun generate ctxt const =
+  let 
+     fun strong_conn_of gr keys =
+      Graph.strong_conn (Graph.subgraph (member (op =) (Graph.all_succs gr keys)) gr)
+    val gr = Predicate_Compile_Core.intros_graph_of ctxt
+    val scc = strong_conn_of gr const
+    val constant_table = mk_constant_table (flat scc)
+  in
+    apfst flat (fold_map (translate_intros ctxt gr) (flat scc) constant_table)
+  end
+
+(* transform logic program *)
+
+(** ensure groundness of terms before negation **)
+
+fun add_vars (Var x) vs = insert (op =) x vs
+  | add_vars (Cons c) vs = vs
+  | add_vars (AppF (f, args)) vs = fold add_vars args vs
+
+fun string_of_typ (Type (s, Ts)) = Long_Name.base_name s
+
+fun mk_groundness_prems ts =
+  let
+    val vars = fold add_vars ts []
+    fun mk_ground v =
+      Rel ("ground", [Var v])
+  in
+    map mk_ground vars
+  end
+
+fun ensure_groundness_prem (NotRel (c, ts)) = Conj (mk_groundness_prems ts @ [NotRel (c, ts)]) 
+  | ensure_groundness_prem (NotEq (l, r)) = Conj (mk_groundness_prems [l, r] @ [NotEq (l, r)])
+  | ensure_groundness_prem (Conj ps) = Conj (map ensure_groundness_prem ps)
+  | ensure_groundness_prem p = p
+
+fun ensure_groundness_before_negation p =
+  map (apsnd ensure_groundness_prem) p
+
+(* code printer *)
+
+fun write_term (Var v) = first_upper v
+  | write_term (Cons c) = c
+  | write_term (AppF (f, args)) = f ^ "(" ^ space_implode ", " (map write_term args) ^ ")" 
+
+fun write_rel (pred, args) =
+  pred ^ "(" ^ space_implode ", " (map write_term args) ^ ")" 
+
+fun write_prem (Conj prems) = space_implode ", " (map write_prem prems)
+  | write_prem (Rel p) = write_rel p  
+  | write_prem (NotRel p) = "not(" ^ write_rel p ^ ")"
+  | write_prem (Eq (l, r)) = write_term l ^ " = " ^ write_term r
+  | write_prem (NotEq (l, r)) = write_term l ^ " \\= " ^ write_term r
+
+fun write_clause (head, prem) =
+  write_rel head ^ (if prem = Conj [] then "." else " :- " ^ write_prem prem ^ ".")
+
+fun write_program p =
+  cat_lines (map write_clause p) 
+
+(** query templates **)
+
+fun query_first rel vnames =
+  "eval :- once("  ^ rel ^ "(" ^ space_implode ", " vnames ^ ")),\n" ^
+  "writef('" ^ space_implode ";" (map (fn v => v ^ " = %w") vnames) ^
+  "\\n', [" ^ space_implode ", " vnames ^ "]).\n"
+  
+fun query_firstn n rel vnames =
+  "eval :- findnsols(" ^ string_of_int n ^ ", (" ^ space_implode ", " vnames ^ "), " ^
+    rel ^ "(" ^ space_implode ", " vnames ^ "), Sols), writelist(Sols).\n" ^
+    "writelist([]).\n" ^
+    "writelist([(" ^ space_implode ", " vnames ^ ")|T]) :- " ^
+    "writef('" ^ space_implode ";" (map (fn v => v ^ " = %w") vnames) ^
+    "\\n', [" ^ space_implode ", " vnames ^ "]), writelist(T).\n"
+  
+val prelude =
+  "#!/usr/bin/swipl -q -t main -f\n\n" ^
+  ":- use_module(library('dialect/ciao/aggregates')).\n" ^
+  ":- style_check(-singleton).\n\n" ^
+  "main :- catch(eval, E, (print_message(error, E), fail)), halt.\n" ^
+  "main :- halt(1).\n"
+
+(* parsing prolog solution *)
+
+val scan_atom =
+  Scan.many1 (fn s => Symbol.is_ascii_lower s orelse Symbol.is_ascii_quasi s)
+
+val scan_var =
+  Scan.many1
+    (fn s => Symbol.is_ascii_upper s orelse Symbol.is_ascii_digit s orelse Symbol.is_ascii_quasi s)
+
+val scan_ident =
+  Scan.repeat (Scan.one
+    (fn s => Symbol.is_ascii_letter s orelse Symbol.is_ascii_digit s orelse Symbol.is_ascii_quasi s))
+
+fun dest_Char (Symbol.Char s) = s
+
+val string_of = concat o map (dest_Char o Symbol.decode)
+
+val is_atom_ident = forall Symbol.is_ascii_lower
+
+val is_var_ident =
+  forall (fn s => Symbol.is_ascii_upper s orelse Symbol.is_ascii_digit s orelse Symbol.is_ascii_quasi s)
+
+fun scan_terms xs = (((scan_term --| $$ ",") ::: scan_terms)
+  || (scan_term >> single)) xs
+and scan_term xs =
+  ((scan_var >> (Var o string_of))
+  || ((scan_atom -- ($$ "(" |-- scan_terms --| $$ ")"))
+    >> (fn (f, ts) => AppF (string_of f, ts)))
+  || (scan_atom >> (Cons o string_of))) xs
+
+val parse_term = fst o Scan.finite Symbol.stopper
+    (Scan.error (!! (fn _ => raise Fail "parsing prolog output failed")) scan_term)
+  o explode
+  
+fun parse_solutions sol =
+  let
+    fun dest_eq s = case space_explode "=" s of
+        (l :: r :: []) => parse_term (unprefix " " r)
+      | _ => raise Fail "unexpected equation in prolog output"
+    fun parse_solution s = map dest_eq (space_explode ";" s)
+  in
+    map parse_solution (fst (split_last (space_explode "\n" sol)))
+  end 
+  
+(* calling external interpreter and getting results *)
+
+fun run p query_rel vnames nsols =
+  let
+    val cmd = Path.named_root
+    val query = case nsols of NONE => query_first | SOME n => query_firstn n 
+    val prog = prelude ^ query query_rel vnames ^ write_program p
+    val _ = tracing ("Generated prolog program:\n" ^ prog)
+    val prolog_file = File.tmp_path (Path.basic "prolog_file")
+    val _ = File.write prolog_file prog
+    val (solution, _) = bash_output ("/usr/local/bin/swipl -f " ^ File.shell_path prolog_file)
+    val _ = tracing ("Prolog returned solution(s):\n" ^ solution)
+    val tss = parse_solutions solution
+  in
+    tss
+  end
+
+(* values command *)
+
+fun restore_term ctxt constant_table (Var s, T) = Free (s, T)
+  | restore_term ctxt constant_table (Cons s, T) = Const (restore_const constant_table s, T)
+  | restore_term ctxt constant_table (AppF (f, args), T) =
+    let
+      val thy = ProofContext.theory_of ctxt
+      val c = restore_const constant_table f
+      val cT = Sign.the_const_type thy c
+      val (argsT, resT) = strip_type cT
+      val subst = Sign.typ_match thy (resT, T) Vartab.empty
+      val argsT' = map (Envir.subst_type subst) argsT
+    in
+      list_comb (Const (c, Envir.subst_type subst cT),
+        map (restore_term ctxt constant_table) (args ~~ argsT'))
+    end
+
+fun values ctxt soln t_compr =
+  let
+    val split = case t_compr of (Const (@{const_name Collect}, _) $ t) => t
+      | _ => error ("Not a set comprehension: " ^ Syntax.string_of_term ctxt t_compr);
+    val (body, Ts, fp) = HOLogic.strip_psplits split;
+    val output_names = Name.variant_list (Term.add_free_names body [])
+      (map (fn i => "x" ^ string_of_int i) (1 upto length Ts))
+    val output_frees = rev (map2 (curry Free) output_names Ts)
+    val body = subst_bounds (output_frees, body)
+    val (pred as Const (name, T), all_args) =
+      case strip_comb body of
+        (Const (name, T), all_args) => (Const (name, T), all_args)
+      | (head, _) => error ("Not a constant: " ^ Syntax.string_of_term ctxt head)
+    val vnames =
+      case try (map (fst o dest_Free)) all_args of
+        SOME vs => vs
+      | NONE => error ("Not only free variables in " ^ commas (map (Syntax.string_of_term ctxt) all_args))
+    val _ = tracing "Generating prolog program..."
+    val (p, constant_table) = generate ctxt [name]
+    val _ = tracing "Running prolog program..."
+    val tss = run p (translate_const constant_table name) (map first_upper vnames) soln
+    val _ = tracing "Restoring terms..."
+    fun mk_set_comprehension t =
+      let
+        val frees = Term.add_frees t []
+        val uu as (uuN, uuT) = singleton (Variable.variant_frees ctxt [t]) ("uu", fastype_of t)
+      in HOLogic.mk_Collect (uuN, uuT, fold (fn (s, T) => fn t => HOLogic.mk_exists (s, T, t))
+        frees (HOLogic.mk_conj (HOLogic.mk_eq (Free uu, t), @{term "True"}))) end
+    val set_comprs = map (fn ts =>
+      mk_set_comprehension (HOLogic.mk_tuple (map (restore_term ctxt constant_table) (ts ~~ Ts)))) tss
+  in
+    foldl1 (HOLogic.mk_binop @{const_name sup}) (set_comprs @ [Free ("...", fastype_of t_compr)])
+  end
+
+fun values_cmd print_modes soln raw_t state =
+  let
+    val ctxt = Toplevel.context_of state
+    val t = Syntax.read_term ctxt raw_t
+    val t' = values ctxt soln t
+    val ty' = Term.type_of t'
+    val ctxt' = Variable.auto_fixes t' ctxt
+    val p = Print_Mode.with_modes print_modes (fn () =>
+      Pretty.block [Pretty.quote (Syntax.pretty_term ctxt' t'), Pretty.fbrk,
+        Pretty.str "::", Pretty.brk 1, Pretty.quote (Syntax.pretty_typ ctxt' ty')]) ();
+  in Pretty.writeln p end;
+
+
+(* renewing the values command for Prolog queries *)
+
+val opt_print_modes =
+  Scan.optional (Parse.$$$ "(" |-- Parse.!!! (Scan.repeat1 Parse.xname --| Parse.$$$ ")")) [];
+
+val _ = Outer_Syntax.improper_command "values" "enumerate and print comprehensions" Keyword.diag
+  (opt_print_modes -- Scan.optional (Parse.nat >> SOME) NONE -- Parse.term
+   >> (fn ((print_modes, soln), t) => Toplevel.keep
+        (values_cmd print_modes soln t)));
+
+end;
diff -r 373351f5f834 -r d44a5f602b8c src/HOL/Tools/Predicate_Compile/predicate_compile_core.ML
--- a/src/HOL/Tools/Predicate_Compile/predicate_compile_core.ML	Fri Jul 30 00:02:25 2010 +0200
+++ b/src/HOL/Tools/Predicate_Compile/predicate_compile_core.ML	Fri Jul 30 15:03:42 2010 +0200
@@ -27,6 +27,7 @@
   val all_modes_of : compilation -> Proof.context -> (string * mode list) list
   val all_random_modes_of : Proof.context -> (string * mode list) list
   val intros_of : Proof.context -> string -> thm list
+  val intros_graph_of : Proof.context -> thm list Graph.T
   val add_intro : thm -> theory -> theory
   val set_elim : thm -> theory -> theory
   val register_alternative_function : string -> mode -> string -> theory -> theory
@@ -295,6 +296,9 @@
 
 val predfun_neg_intro_of = #neg_intro ooo the_predfun_data
 
+val intros_graph_of =
+  Graph.map_nodes (#intros o rep_pred_data) o PredData.get o ProofContext.theory_of
+
 (* diagnostic display functions *)
 
 fun print_modes options modes =
diff -r 373351f5f834 -r d44a5f602b8c src/Tools/Code/code_ml.ML
--- a/src/Tools/Code/code_ml.ML	Fri Jul 30 00:02:25 2010 +0200
+++ b/src/Tools/Code/code_ml.ML	Fri Jul 30 15:03:42 2010 +0200
@@ -987,7 +987,8 @@
       )))
   #> fold (Code_Target.add_reserved target_SML) ML_Syntax.reserved_names
   #> fold (Code_Target.add_reserved target_SML)
-      ["o" (*dictionary projections use it already*), "Fail", "div", "mod" (*standard infixes*), "IntInf"]
+      ["ref" (*rebinding is illegal*), "o" (*dictionary projections use it already*),
+        "Fail", "div", "mod" (*standard infixes*), "IntInf"]
   #> fold (Code_Target.add_reserved target_OCaml) [
       "and", "as", "assert", "begin", "class",
       "constraint", "do", "done", "downto", "else", "end", "exception",