src/HOL/Tools/Predicate_Compile/code_prolog.ML
author wenzelm
Sat Mar 05 17:01:45 2016 +0100 (2016-03-05)
changeset 62519 a564458f94db
parent 61424 c3658c18b7bc
child 62549 9498623b27f0
permissions -rw-r--r--
tuned signature -- clarified modules;
     1 (*  Title:      HOL/Tools/Predicate_Compile/code_prolog.ML
     2     Author:     Lukas Bulwahn, TU Muenchen
     3 
     4 Prototype of an code generator for logic programming languages
     5 (a.k.a. Prolog).
     6 *)
     7 
     8 signature CODE_PROLOG =
     9 sig
    10   type code_options =
    11     {ensure_groundness : bool,
    12      limit_globally : int option,
    13      limited_types : (typ * int) list,
    14      limited_predicates : (string list * int) list,
    15      replacing : ((string * string) * string) list,
    16      manual_reorder : ((string * int) * int list) list}
    17   val set_ensure_groundness : code_options -> code_options
    18   val map_limit_predicates : ((string list * int) list -> (string list * int) list)
    19     -> code_options -> code_options
    20   val code_options_of : theory -> code_options
    21   val map_code_options : (code_options -> code_options) -> theory -> theory
    22 
    23   val prolog_system: string Config.T
    24   val prolog_timeout: real Config.T
    25 
    26   datatype arith_op = Plus | Minus
    27   datatype prol_term = Var of string | Cons of string | AppF of string * prol_term list
    28     | Number of int | ArithOp of arith_op * prol_term list;
    29   datatype prem = Conj of prem list
    30     | Rel of string * prol_term list | NotRel of string * prol_term list
    31     | Eq of prol_term * prol_term | NotEq of prol_term * prol_term
    32     | ArithEq of prol_term * prol_term | NotArithEq of prol_term * prol_term
    33     | Ground of string * typ;
    34 
    35   type clause = ((string * prol_term list) * prem);
    36   type logic_program = clause list;
    37   type constant_table = (string * string) list
    38 
    39   val generate : Predicate_Compile_Aux.mode option * bool ->
    40     Proof.context -> string -> (logic_program * constant_table)
    41   val write_program : logic_program -> string
    42   val run : Proof.context -> logic_program -> (string * prol_term list) ->
    43     string list -> int option -> prol_term list list
    44 
    45   val active : bool Config.T
    46   val test_goals :
    47     Proof.context -> bool -> (string * typ) list -> (term * term list) list ->
    48       Quickcheck.result list
    49 
    50   val trace : bool Unsynchronized.ref
    51 
    52   val replace : ((string * string) * string) -> logic_program -> logic_program
    53 end;
    54 
    55 structure Code_Prolog : CODE_PROLOG =
    56 struct
    57 
    58 (* diagnostic tracing *)
    59 
    60 val trace = Unsynchronized.ref false
    61 
    62 fun tracing s = if !trace then Output.tracing s else ()
    63 
    64 
    65 (* code generation options *)
    66 
    67 type code_options =
    68   {ensure_groundness : bool,
    69    limit_globally : int option,
    70    limited_types : (typ * int) list,
    71    limited_predicates : (string list * int) list,
    72    replacing : ((string * string) * string) list,
    73    manual_reorder : ((string * int) * int list) list}
    74 
    75 
    76 fun set_ensure_groundness {ensure_groundness, limit_globally, limited_types, limited_predicates,
    77   replacing, manual_reorder} =
    78   {ensure_groundness = true, limit_globally = limit_globally, limited_types = limited_types,
    79    limited_predicates = limited_predicates, replacing = replacing,
    80    manual_reorder = manual_reorder}
    81 
    82 fun map_limit_predicates f {ensure_groundness, limit_globally, limited_types, limited_predicates,
    83   replacing, manual_reorder} =
    84   {ensure_groundness = ensure_groundness, limit_globally = limit_globally,
    85    limited_types = limited_types, limited_predicates = f limited_predicates,
    86    replacing = replacing, manual_reorder = manual_reorder}
    87 
    88 fun merge_global_limit (NONE, NONE) = NONE
    89   | merge_global_limit (NONE, SOME n) = SOME n
    90   | merge_global_limit (SOME n, NONE) = SOME n
    91   | merge_global_limit (SOME n, SOME m) = SOME (Int.max (n, m))  (* FIXME odd merge *)
    92 
    93 structure Options = Theory_Data
    94 (
    95   type T = code_options
    96   val empty = {ensure_groundness = false, limit_globally = NONE,
    97     limited_types = [], limited_predicates = [], replacing = [], manual_reorder = []}
    98   val extend = I;
    99   fun merge
   100     ({ensure_groundness = ensure_groundness1, limit_globally = limit_globally1,
   101       limited_types = limited_types1, limited_predicates = limited_predicates1,
   102       replacing = replacing1, manual_reorder = manual_reorder1},
   103      {ensure_groundness = ensure_groundness2, limit_globally = limit_globally2,
   104       limited_types = limited_types2, limited_predicates = limited_predicates2,
   105       replacing = replacing2, manual_reorder = manual_reorder2}) =
   106     {ensure_groundness = ensure_groundness1 orelse ensure_groundness2 (* FIXME odd merge *),
   107      limit_globally = merge_global_limit (limit_globally1, limit_globally2),
   108      limited_types = AList.merge (op =) (K true) (limited_types1, limited_types2),
   109      limited_predicates = AList.merge (op =) (K true) (limited_predicates1, limited_predicates2),
   110      manual_reorder = AList.merge (op =) (K true) (manual_reorder1, manual_reorder2),
   111      replacing = Library.merge (op =) (replacing1, replacing2)};
   112 );
   113 
   114 val code_options_of = Options.get
   115 
   116 val map_code_options = Options.map
   117 
   118 
   119 (* system configuration *)
   120 
   121 datatype prolog_system = SWI_PROLOG | YAP
   122 
   123 fun string_of_system SWI_PROLOG = "swiprolog"
   124   | string_of_system YAP = "yap"
   125 
   126 val prolog_system = Attrib.setup_config_string @{binding prolog_system} (K "swiprolog")
   127 
   128 fun get_prolog_system ctxt =
   129   (case Config.get ctxt prolog_system of
   130     "swiprolog" => SWI_PROLOG
   131   | "yap" => YAP
   132   | name => error ("Bad prolog system: " ^ quote name ^ " (\"swiprolog\" or \"yap\" expected)"))
   133 
   134 
   135 val prolog_timeout = Attrib.setup_config_real @{binding prolog_timeout} (K 10.0)
   136 
   137 fun get_prolog_timeout ctxt = seconds (Config.get ctxt prolog_timeout)
   138 
   139 
   140 (* internal program representation *)
   141 
   142 datatype arith_op = Plus | Minus
   143 
   144 datatype prol_term = Var of string | Cons of string | AppF of string * prol_term list
   145   | Number of int | ArithOp of arith_op * prol_term list;
   146 
   147 fun dest_Var (Var v) = v
   148 
   149 fun add_vars (Var v) = insert (op =) v
   150   | add_vars (ArithOp (_, ts)) = fold add_vars ts
   151   | add_vars (AppF (_, ts)) = fold add_vars ts
   152   | add_vars _ = I
   153 
   154 fun map_vars f (Var v) = Var (f v)
   155   | map_vars f (ArithOp (opr, ts)) = ArithOp (opr, map (map_vars f) ts)
   156   | map_vars f (AppF (fs, ts)) = AppF (fs, map (map_vars f) ts)
   157   | map_vars f t = t
   158 
   159 fun maybe_AppF (c, []) = Cons c
   160   | maybe_AppF (c, xs) = AppF (c, xs)
   161 
   162 fun is_Var (Var _) = true
   163   | is_Var _ = false
   164 
   165 fun is_arith_term (Var _) = true
   166   | is_arith_term (Number _) = true
   167   | is_arith_term (ArithOp (_, operands)) = forall is_arith_term operands
   168   | is_arith_term _ = false
   169 
   170 fun string_of_prol_term (Var s) = "Var " ^ s
   171   | string_of_prol_term (Cons s) = "Cons " ^ s
   172   | string_of_prol_term (AppF (f, args)) = f ^ "(" ^ commas (map string_of_prol_term args) ^ ")"
   173   | string_of_prol_term (Number n) = "Number " ^ string_of_int n
   174 
   175 datatype prem = Conj of prem list
   176   | Rel of string * prol_term list | NotRel of string * prol_term list
   177   | Eq of prol_term * prol_term | NotEq of prol_term * prol_term
   178   | ArithEq of prol_term * prol_term | NotArithEq of prol_term * prol_term
   179   | Ground of string * typ;
   180 
   181 fun dest_Rel (Rel (c, ts)) = (c, ts)
   182 
   183 fun map_term_prem f (Conj prems) = Conj (map (map_term_prem f) prems)
   184   | map_term_prem f (Rel (r, ts)) = Rel (r, map f ts)
   185   | map_term_prem f (NotRel (r, ts)) = NotRel (r, map f ts)
   186   | map_term_prem f (Eq (l, r)) = Eq (f l, f r)
   187   | map_term_prem f (NotEq (l, r)) = NotEq (f l, f r)
   188   | map_term_prem f (ArithEq (l, r)) = ArithEq (f l, f r)
   189   | map_term_prem f (NotArithEq (l, r)) = NotArithEq (f l, f r)
   190   | map_term_prem f (Ground (v, T)) = Ground (dest_Var (f (Var v)), T)
   191 
   192 fun fold_prem_terms f (Conj prems) = fold (fold_prem_terms f) prems
   193   | fold_prem_terms f (Rel (_, ts)) = fold f ts
   194   | fold_prem_terms f (NotRel (_, ts)) = fold f ts
   195   | fold_prem_terms f (Eq (l, r)) = f l #> f r
   196   | fold_prem_terms f (NotEq (l, r)) = f l #> f r
   197   | fold_prem_terms f (ArithEq (l, r)) = f l #> f r
   198   | fold_prem_terms f (NotArithEq (l, r)) = f l #> f r
   199   | fold_prem_terms f (Ground (v, T)) = f (Var v)
   200 
   201 type clause = ((string * prol_term list) * prem);
   202 
   203 type logic_program = clause list;
   204 
   205 
   206 (* translation from introduction rules to internal representation *)
   207 
   208 fun mk_conform f empty avoid name =
   209   let
   210     fun dest_Char (Symbol.Char c) = c
   211     val name' = space_implode "" (map (dest_Char o Symbol.decode)
   212       (filter (fn s => Symbol.is_ascii_letter s orelse Symbol.is_ascii_digit s)
   213         (Symbol.explode name)))
   214     val name'' = f (if name' = "" then empty else name')
   215   in if member (op =) avoid name'' then singleton (Name.variant_list avoid) name'' else name'' end
   216 
   217 
   218 (** constant table **)
   219 
   220 type constant_table = (string * string) list
   221 
   222 fun declare_consts consts constant_table =
   223   let
   224     fun update' c table =
   225       if AList.defined (op =) table c then table else
   226         let
   227           val c' = mk_conform (Name.enforce_case false) "pred" (map snd table) (Long_Name.base_name c)
   228         in
   229           AList.update (op =) (c, c') table
   230         end
   231   in
   232     fold update' consts constant_table
   233   end
   234 
   235 fun translate_const constant_table c =
   236   (case AList.lookup (op =) constant_table c of
   237     SOME c' => c'
   238   | NONE => error ("No such constant: " ^ c))
   239 
   240 fun inv_lookup _ [] _ = NONE
   241   | inv_lookup eq ((key, value)::xs) value' =
   242       if eq (value', value) then SOME key
   243       else inv_lookup eq xs value'
   244 
   245 fun restore_const constant_table c =
   246   (case inv_lookup (op =) constant_table c of
   247     SOME c' => c'
   248   | NONE => error ("No constant corresponding to "  ^ c))
   249 
   250 
   251 (** translation of terms, literals, premises, and clauses **)
   252 
   253 fun translate_arith_const @{const_name "Groups.plus_class.plus"} = SOME Plus
   254   | translate_arith_const @{const_name "Groups.minus_class.minus"} = SOME Minus
   255   | translate_arith_const _ = NONE
   256 
   257 fun mk_nat_term constant_table n =
   258   let
   259     val zero = translate_const constant_table @{const_name "Groups.zero_class.zero"}
   260     val Suc = translate_const constant_table @{const_name "Suc"}
   261   in funpow n (fn t => AppF (Suc, [t])) (Cons zero) end
   262 
   263 fun translate_term ctxt constant_table t =
   264   (case try HOLogic.dest_number t of
   265     SOME (@{typ "int"}, n) => Number n
   266   | SOME (@{typ "nat"}, n) => mk_nat_term constant_table n
   267   | NONE =>
   268       (case strip_comb t of
   269         (Free (v, T), []) => Var v
   270       | (Const (c, _), []) => Cons (translate_const constant_table c)
   271       | (Const (c, _), args) =>
   272           (case translate_arith_const c of
   273             SOME aop => ArithOp (aop, map (translate_term ctxt constant_table) args)
   274           | NONE =>
   275               AppF (translate_const constant_table c, map (translate_term ctxt constant_table) args))
   276       | _ => error ("illegal term for translation: " ^ Syntax.string_of_term ctxt t)))
   277 
   278 fun translate_literal ctxt constant_table t =
   279   (case strip_comb t of
   280     (Const (@{const_name HOL.eq}, _), [l, r]) =>
   281       let
   282         val l' = translate_term ctxt constant_table l
   283         val r' = translate_term ctxt constant_table r
   284       in
   285         (if is_Var l' andalso is_arith_term r' andalso not (is_Var r') then ArithEq else Eq)
   286           (l', r')
   287       end
   288   | (Const (c, _), args) =>
   289       Rel (translate_const constant_table c, map (translate_term ctxt constant_table) args)
   290   | _ => error ("illegal literal for translation: " ^ Syntax.string_of_term ctxt t))
   291 
   292 fun NegRel_of (Rel lit) = NotRel lit
   293   | NegRel_of (Eq eq) = NotEq eq
   294   | NegRel_of (ArithEq eq) = NotArithEq eq
   295 
   296 fun mk_groundness_prems t = map Ground (Term.add_frees t [])
   297 
   298 fun translate_prem ensure_groundness ctxt constant_table t =
   299   (case try HOLogic.dest_not t of
   300     SOME t =>
   301       if ensure_groundness then
   302         Conj (mk_groundness_prems t @ [NegRel_of (translate_literal ctxt constant_table t)])
   303       else
   304         NegRel_of (translate_literal ctxt constant_table t)
   305   | NONE => translate_literal ctxt constant_table t)
   306 
   307 fun imp_prems_conv cv ct =
   308   (case Thm.term_of ct of
   309     Const (@{const_name Pure.imp}, _) $ _ $ _ =>
   310       Conv.combination_conv (Conv.arg_conv cv) (imp_prems_conv cv) ct
   311   | _ => Conv.all_conv ct)
   312 
   313 fun preprocess_intro thy rule =
   314   Conv.fconv_rule
   315     (imp_prems_conv
   316       (HOLogic.Trueprop_conv (Conv.try_conv (Conv.rewr_conv @{thm Predicate.eq_is_eq}))))
   317     (Thm.transfer thy rule)
   318 
   319 fun translate_intros ensure_groundness ctxt gr const constant_table =
   320   let
   321     val intros = map (preprocess_intro (Proof_Context.theory_of ctxt)) (Graph.get_node gr const)
   322     val (intros', ctxt') = Variable.import_terms true (map Thm.prop_of intros) ctxt
   323     val constant_table' = declare_consts (fold Term.add_const_names intros' []) constant_table
   324     fun translate_intro intro =
   325       let
   326         val head = HOLogic.dest_Trueprop (Logic.strip_imp_concl intro)
   327         val prems = map HOLogic.dest_Trueprop (Logic.strip_imp_prems intro)
   328         val prems' = Conj (map (translate_prem ensure_groundness ctxt' constant_table') prems)
   329         val clause = (dest_Rel (translate_literal ctxt' constant_table' head), prems')
   330       in clause end
   331   in
   332     (map translate_intro intros', constant_table')
   333   end
   334 
   335 fun depending_preds_of (key, intros) =
   336   fold Term.add_const_names (map Thm.prop_of intros) []
   337 
   338 fun add_edges edges_of key G =
   339   let
   340     fun extend' key (G, visited) =
   341       (case try (Graph.get_node G) key of
   342         SOME v =>
   343           let
   344             val new_edges = filter (fn k => is_some (try (Graph.get_node G) k)) (edges_of (key, v))
   345             val (G', visited') = fold extend'
   346               (subtract (op =) (key :: visited) new_edges) (G, key :: visited)
   347           in
   348             (fold (Graph.add_edge o (pair key)) new_edges G', visited')
   349           end
   350       | NONE => (G, visited))
   351   in
   352     fst (extend' key (G, []))
   353   end
   354 
   355 fun print_intros ctxt gr consts =
   356   tracing (cat_lines (map (fn const =>
   357     "Constant " ^ const ^ "has intros:\n" ^
   358     cat_lines (map (Thm.string_of_thm ctxt) (Graph.get_node gr const))) consts))
   359 
   360 
   361 (* translation of moded predicates *)
   362 
   363 (** generating graph of moded predicates **)
   364 
   365 (* could be moved to Predicate_Compile_Core *)
   366 fun requires_modes polarity cls =
   367   let
   368     fun req_mode_of pol (t, derivation) =
   369       (case fst (strip_comb t) of
   370         Const (c, _) => SOME (c, (pol, Predicate_Compile_Core.head_mode_of derivation))
   371       | _ => NONE)
   372     fun req (Predicate_Compile_Aux.Prem t, derivation) =
   373           req_mode_of polarity (t, derivation)
   374       | req (Predicate_Compile_Aux.Negprem t, derivation) =
   375           req_mode_of (not polarity) (t, derivation)
   376       | req _ = NONE
   377   in
   378     maps (fn (_, prems) => map_filter req prems) cls
   379   end
   380 
   381 structure Mode_Graph =
   382   Graph(
   383     type key = string * (bool * Predicate_Compile_Aux.mode)
   384     val ord = prod_ord fast_string_ord (prod_ord bool_ord Predicate_Compile_Aux.mode_ord)
   385   )
   386 
   387 fun mk_moded_clauses_graph ctxt scc gr =
   388   let
   389     val options = Predicate_Compile_Aux.default_options
   390     val mode_analysis_options =
   391       {use_generators = true, reorder_premises = true, infer_pos_and_neg_modes = true}
   392     fun infer prednames (gr, (pos_modes, neg_modes, random)) =
   393       let
   394         val (lookup_modes, lookup_neg_modes, needs_random) =
   395           ((fn s => the (AList.lookup (op =) pos_modes s)),
   396            (fn s => the (AList.lookup (op =) neg_modes s)),
   397            (fn s => member (op =) (the (AList.lookup (op =) random s))))
   398         val (preds, all_vs, param_vs, all_modes, clauses) =
   399           Predicate_Compile_Core.prepare_intrs options ctxt prednames
   400             (maps (Core_Data.intros_of ctxt) prednames)
   401         val ((moded_clauses, random'), _) =
   402           Mode_Inference.infer_modes mode_analysis_options options
   403             (lookup_modes, lookup_neg_modes, needs_random) ctxt preds all_modes param_vs clauses
   404         val modes = map (fn (p, mps) => (p, map fst mps)) moded_clauses
   405         val pos_modes' = map (apsnd (map_filter (fn (true, m) => SOME m | _ => NONE))) modes
   406         val neg_modes' = map (apsnd (map_filter (fn (false, m) => SOME m | _ => NONE))) modes
   407         val _ =
   408           tracing ("Inferred modes:\n" ^
   409             cat_lines (map (fn (s, ms) => s ^ ": " ^ commas (map
   410               (fn (p, m) =>
   411                 Predicate_Compile_Aux.string_of_mode m ^ (if p then "pos" else "neg")) ms)) modes))
   412         val gr' = gr
   413           |> fold (fn (p, mps) => fold (fn (mode, cls) =>
   414                 Mode_Graph.new_node ((p, mode), cls)) mps)
   415             moded_clauses
   416           |> fold (fn (p, mps) => fold (fn (mode, cls) => fold (fn req =>
   417               Mode_Graph.add_edge ((p, mode), req)) (requires_modes (fst mode) cls)) mps)
   418             moded_clauses
   419       in
   420         (gr', (AList.merge (op =) (op =) (pos_modes, pos_modes'),
   421           AList.merge (op =) (op =) (neg_modes, neg_modes'),
   422           AList.merge (op =) (op =) (random, random')))
   423       end
   424   in
   425     fst (fold infer (rev scc) (Mode_Graph.empty, ([], [], [])))
   426   end
   427 
   428 fun declare_moded_predicate moded_preds table =
   429   let
   430     fun update' (p as (pred, (pol, mode))) table =
   431       if AList.defined (op =) table p then table else
   432         let
   433           val name = Long_Name.base_name pred ^ (if pol then "p" else "n")
   434             ^ Predicate_Compile_Aux.ascii_string_of_mode mode
   435           val p' = mk_conform (Name.enforce_case false) "pred" (map snd table) name
   436         in
   437           AList.update (op =) (p, p') table
   438         end
   439   in
   440     fold update' moded_preds table
   441   end
   442 
   443 fun mk_program ctxt moded_gr moded_preds (prog, (moded_pred_table, constant_table)) =
   444   let
   445     val moded_pred_table' = declare_moded_predicate moded_preds moded_pred_table
   446     fun mk_literal pol derivation constant_table' t =
   447       let
   448         val (p, args) = strip_comb t
   449         val mode = Predicate_Compile_Core.head_mode_of derivation
   450         val name = fst (dest_Const p)
   451 
   452         val p' = the (AList.lookup (op =) moded_pred_table' (name, (pol, mode)))
   453         val args' = map (translate_term ctxt constant_table') args
   454       in
   455         Rel (p', args')
   456       end
   457     fun mk_prem pol (indprem, derivation) constant_table =
   458       (case indprem of
   459         Predicate_Compile_Aux.Generator (s, T) => (Ground (s, T), constant_table)
   460       | _ =>
   461         declare_consts (Term.add_const_names (Predicate_Compile_Aux.dest_indprem indprem) [])
   462           constant_table
   463         |> (fn constant_table' =>
   464           (case indprem of Predicate_Compile_Aux.Negprem t =>
   465             NegRel_of (mk_literal (not pol) derivation constant_table' t)
   466           | _ =>
   467             mk_literal pol derivation constant_table' (Predicate_Compile_Aux.dest_indprem indprem),
   468               constant_table')))
   469     fun mk_clause pred_name pol (ts, prems) (prog, constant_table) =
   470       let
   471         val constant_table' = declare_consts (fold Term.add_const_names ts []) constant_table
   472         val args = map (translate_term ctxt constant_table') ts
   473         val (prems', constant_table'') = fold_map (mk_prem pol) prems constant_table'
   474       in
   475         (((pred_name, args), Conj prems') :: prog, constant_table'')
   476       end
   477     fun mk_clauses (pred, mode as (pol, _)) =
   478       let
   479         val clauses = Mode_Graph.get_node moded_gr (pred, mode)
   480         val pred_name = the (AList.lookup (op =) moded_pred_table' (pred, mode))
   481       in
   482         fold (mk_clause pred_name pol) clauses
   483       end
   484   in
   485     apsnd (pair moded_pred_table') (fold mk_clauses moded_preds (prog, constant_table))
   486   end
   487 
   488 fun generate (use_modes, ensure_groundness) ctxt const =
   489   let
   490     fun strong_conn_of gr keys =
   491       Graph.strong_conn (Graph.restrict (member (op =) (Graph.all_succs gr keys)) gr)
   492     val gr = Core_Data.intros_graph_of ctxt
   493     val gr' = add_edges depending_preds_of const gr
   494     val scc = strong_conn_of gr' [const]
   495     val initial_constant_table =
   496       declare_consts [@{const_name "Groups.zero_class.zero"}, @{const_name "Suc"}] []
   497   in
   498     (case use_modes of
   499       SOME mode =>
   500         let
   501           val moded_gr = mk_moded_clauses_graph ctxt scc gr
   502           val moded_gr' = Mode_Graph.restrict
   503             (member (op =) (Mode_Graph.all_succs moded_gr [(const, (true, mode))])) moded_gr
   504           val scc = Mode_Graph.strong_conn moded_gr'
   505         in
   506           apfst rev (apsnd snd
   507             (fold (mk_program ctxt moded_gr') (rev scc) ([], ([], initial_constant_table))))
   508         end
   509     | NONE =>
   510         let
   511           val _ = print_intros ctxt gr (flat scc)
   512           val constant_table = declare_consts (flat scc) initial_constant_table
   513         in
   514           apfst flat
   515             (fold_map (translate_intros ensure_groundness ctxt gr) (flat scc) constant_table)
   516         end)
   517   end
   518 
   519 
   520 (* implementation for fully enumerating predicates and
   521   for size-limited predicates for enumerating the values of a datatype upto a specific size *)
   522 
   523 fun add_ground_typ (Conj prems) = fold add_ground_typ prems
   524   | add_ground_typ (Ground (_, T)) = insert (op =) T
   525   | add_ground_typ _ = I
   526 
   527 fun mk_relname (Type (Tcon, Targs)) =
   528       Name.enforce_case false (Long_Name.base_name Tcon) ^ space_implode "_" (map mk_relname Targs)
   529   | mk_relname _ = raise Fail "unexpected type"
   530 
   531 fun mk_lim_relname T = "lim_" ^  mk_relname T
   532 
   533 fun is_recursive_constr T (Const (constr_name, T')) = member (op =) (binder_types T') T
   534 
   535 fun mk_ground_impl ctxt limited_types (T as Type (Tcon, Targs)) (seen, constant_table) =
   536   if member (op =) seen T then ([], (seen, constant_table))
   537   else
   538     let
   539       val (limited, size) =
   540         (case AList.lookup (op =) limited_types T of
   541           SOME s => (true, s)
   542         | NONE => (false, 0))
   543       val rel_name = (if limited then mk_lim_relname else mk_relname) T
   544       fun mk_impl (Const (constr_name, cT), recursive) (seen, constant_table) =
   545         let
   546           val constant_table' = declare_consts [constr_name] constant_table
   547           val Ts = binder_types cT
   548           val (rec_clauses, (seen', constant_table'')) =
   549             fold_map (mk_ground_impl ctxt limited_types) Ts (seen, constant_table')
   550           val vars = map (fn i => Var ("x" ^ string_of_int i)) (1 upto (length Ts))
   551           val lim_var =
   552             if limited then
   553               if recursive then [AppF ("suc", [Var "Lim"])]
   554               else [Var "Lim"]
   555             else []
   556           fun mk_prem v T' =
   557             if limited andalso T' = T then Rel (mk_lim_relname T', [Var "Lim", v])
   558             else Rel (mk_relname T', [v])
   559           val clause =
   560             ((rel_name, lim_var @ [maybe_AppF (translate_const constant_table'' constr_name, vars)]),
   561              Conj (map2 mk_prem vars Ts))
   562         in
   563           (clause :: flat rec_clauses, (seen', constant_table''))
   564         end
   565       val constrs = Function_Lib.inst_constrs_of ctxt T
   566       val constrs' = (constrs ~~ map (is_recursive_constr T) constrs)
   567         |> (fn cs => filter_out snd cs @ filter snd cs)
   568       val (clauses, constant_table') =
   569         apfst flat (fold_map mk_impl constrs' (T :: seen, constant_table))
   570       val size_term = funpow size (fn t => AppF ("suc", [t])) (Cons "zero")
   571     in
   572       ((if limited then
   573         cons ((mk_relname T, [Var "x"]), Rel (mk_lim_relname T, [size_term, Var "x"]))
   574       else I) clauses, constant_table')
   575     end
   576  | mk_ground_impl ctxt _ T (seen, constant_table) =
   577    raise Fail ("unexpected type :" ^ Syntax.string_of_typ ctxt T)
   578 
   579 fun replace_ground (Conj prems) = Conj (map replace_ground prems)
   580   | replace_ground (Ground (x, T)) =
   581     Rel (mk_relname T, [Var x])
   582   | replace_ground p = p
   583 
   584 fun add_ground_predicates ctxt limited_types (p, constant_table) =
   585   let
   586     val ground_typs = fold (add_ground_typ o snd) p []
   587     val (grs, (_, constant_table')) =
   588       fold_map (mk_ground_impl ctxt limited_types) ground_typs ([], constant_table)
   589     val p' = map (apsnd replace_ground) p
   590   in
   591     ((flat grs) @ p', constant_table')
   592   end
   593 
   594 
   595 (* make depth-limited version of predicate *)
   596 
   597 fun mk_lim_rel_name rel_name = "lim_" ^ rel_name
   598 
   599 fun mk_depth_limited rel_names ((rel_name, ts), prem) =
   600   let
   601     fun has_positive_recursive_prems (Conj prems) = exists has_positive_recursive_prems prems
   602       | has_positive_recursive_prems (Rel (rel, ts)) = member (op =) rel_names rel
   603       | has_positive_recursive_prems _ = false
   604     fun mk_lim_prem (Conj prems) = Conj (map mk_lim_prem prems)
   605       | mk_lim_prem (p as Rel (rel, ts)) =
   606         if member (op =) rel_names rel then Rel (mk_lim_rel_name rel, Var "Lim" :: ts) else p
   607       | mk_lim_prem p = p
   608   in
   609     if has_positive_recursive_prems prem then
   610       ((mk_lim_rel_name rel_name, (AppF ("suc", [Var "Lim"]))  :: ts), mk_lim_prem prem)
   611     else
   612       ((mk_lim_rel_name rel_name, (Var "Lim") :: ts), prem)
   613   end
   614 
   615 fun nat_term_of n = funpow n (fn t => AppF ("suc", [t])) (Cons "zero")
   616 
   617 fun add_limited_predicates limited_predicates (p, constant_table) =
   618   let
   619     fun add (rel_names, limit) p =
   620       let
   621         val clauses = filter (fn ((rel, _), _) => member (op =) rel_names rel) p
   622         val clauses' = map (mk_depth_limited rel_names) clauses
   623         fun mk_entry_clause rel_name =
   624           let
   625             val nargs = length (snd (fst
   626               (the (find_first (fn ((rel, _), _) => rel = rel_name) clauses))))
   627             val vars = map (fn i => Var ("x" ^ string_of_int i)) (1 upto nargs)
   628           in
   629             (("limited_" ^ rel_name, vars), Rel ("lim_" ^ rel_name, nat_term_of limit :: vars))
   630           end
   631       in (p @ (map mk_entry_clause rel_names) @ clauses') end
   632   in
   633     (fold add limited_predicates p, constant_table)
   634   end
   635 
   636 
   637 (* replace predicates in clauses *)
   638 
   639 (* replace (A, B, C) p = replace A by B in clauses of C *)
   640 fun replace ((from, to), location) p =
   641   let
   642     fun replace_prem (Conj prems) = Conj (map replace_prem prems)
   643       | replace_prem (r as Rel (rel, ts)) =
   644           if rel = from then Rel (to, ts) else r
   645       | replace_prem r = r
   646   in
   647     map
   648       (fn ((rel, args), prem) => ((rel, args), (if rel = location then replace_prem else I) prem))
   649       p
   650   end
   651 
   652 
   653 (* reorder manually : reorder premises of ith clause of predicate p by a permutation perm *)
   654 
   655 fun reorder_manually reorder p =
   656   let
   657     fun reorder' ((rel, args), prem) seen =
   658       let
   659         val seen' = AList.map_default (op =) (rel, 0) (fn x => x + 1) seen
   660         val i = the (AList.lookup (op =) seen' rel)
   661         val perm = AList.lookup (op =) reorder (rel, i)
   662         val prem' =
   663           (case perm of
   664             SOME p => (case prem of Conj prems => Conj (map (nth prems) p) | _ => prem)
   665           | NONE => prem)
   666       in (((rel, args), prem'), seen') end
   667   in
   668     fst (fold_map reorder' p [])
   669   end
   670 
   671 
   672 (* rename variables to prolog-friendly names *)
   673 
   674 fun rename_vars_term renaming = map_vars (fn v => the (AList.lookup (op =) renaming v))
   675 
   676 fun rename_vars_prem renaming = map_term_prem (rename_vars_term renaming)
   677 
   678 fun mk_renaming v renaming =
   679   (v, mk_conform (Name.enforce_case true) "Var" (map snd renaming) v) :: renaming
   680 
   681 fun rename_vars_clause ((rel, args), prem) =
   682   let
   683     val vars = fold_prem_terms add_vars prem (fold add_vars args [])
   684     val renaming = fold mk_renaming vars []
   685   in ((rel, map (rename_vars_term renaming) args), rename_vars_prem renaming prem) end
   686 
   687 
   688 (* limit computation globally by some threshold *)
   689 
   690 fun limit_globally limit const_name (p, constant_table) =
   691   let
   692     val rel_names = fold (fn ((r, _), _) => insert (op =) r) p []
   693     val p' = map (mk_depth_limited rel_names) p
   694     val rel_name = translate_const constant_table const_name
   695     val nargs = length (snd (fst
   696       (the (find_first (fn ((rel, _), _) => rel = rel_name) p))))
   697     val vars = map (fn i => Var ("x" ^ string_of_int i)) (1 upto nargs)
   698     val entry_clause = ((rel_name, vars), Rel ("lim_" ^ rel_name, nat_term_of limit :: vars))
   699     val p'' = filter_out (fn ((rel, _), _) => rel = rel_name) p
   700   in
   701     (entry_clause :: p' @ p'', constant_table)
   702   end
   703 
   704 
   705 (* post processing of generated prolog program *)
   706 
   707 fun post_process ctxt (options: code_options) const_name (p, constant_table) =
   708   (p, constant_table)
   709   |> (case #limit_globally options of
   710         SOME limit => limit_globally limit const_name
   711       | NONE => I)
   712   |> (if #ensure_groundness options then
   713         add_ground_predicates ctxt (#limited_types options)
   714       else I)
   715   |> tap (fn _ => tracing "Adding limited predicates...")
   716   |> add_limited_predicates (#limited_predicates options)
   717   |> tap (fn _ => tracing "Replacing predicates...")
   718   |> apfst (fold replace (#replacing options))
   719   |> apfst (reorder_manually (#manual_reorder options))
   720   |> apfst (map rename_vars_clause)
   721 
   722 
   723 (* code printer *)
   724 
   725 fun write_arith_op Plus = "+"
   726   | write_arith_op Minus = "-"
   727 
   728 fun write_term (Var v) = v
   729   | write_term (Cons c) = c
   730   | write_term (AppF (f, args)) =
   731       f ^ "(" ^ space_implode ", " (map write_term args) ^ ")"
   732   | write_term (ArithOp (oper, [a1, a2])) =
   733       write_term a1 ^ " " ^ write_arith_op oper ^ " " ^ write_term a2
   734   | write_term (Number n) = string_of_int n
   735 
   736 fun write_rel (pred, args) =
   737   pred ^ "(" ^ space_implode ", " (map write_term args) ^ ")"
   738 
   739 fun write_prem (Conj prems) = space_implode ", " (map write_prem prems)
   740   | write_prem (Rel p) = write_rel p
   741   | write_prem (NotRel p) = "not(" ^ write_rel p ^ ")"
   742   | write_prem (Eq (l, r)) = write_term l ^ " = " ^ write_term r
   743   | write_prem (NotEq (l, r)) = write_term l ^ " \\= " ^ write_term r
   744   | write_prem (ArithEq (l, r)) = write_term l ^ " is " ^ write_term r
   745   | write_prem (NotArithEq (l, r)) = write_term l ^ " =\\= " ^ write_term r
   746   | write_prem _ = raise Fail "Not a valid prolog premise"
   747 
   748 fun write_clause (head, prem) =
   749   write_rel head ^ (if prem = Conj [] then "." else " :- " ^ write_prem prem ^ ".")
   750 
   751 fun write_program p =
   752   cat_lines (map write_clause p)
   753 
   754 
   755 (* query templates *)
   756 
   757 (** query and prelude for swi-prolog **)
   758 
   759 fun swi_prolog_query_first (rel, args) vnames =
   760   "eval :- once("  ^ rel ^ "(" ^ space_implode ", " (map write_term args) ^ ")),\n" ^
   761   "writef('" ^ space_implode ";" (map (fn v => v ^ " = %w") vnames) ^
   762   "\\n', [" ^ space_implode ", " vnames ^ "]).\n"
   763 
   764 fun swi_prolog_query_firstn n (rel, args) vnames =
   765   "eval :- findnsols(" ^ string_of_int n ^ ", (" ^ space_implode ", " vnames ^ "), " ^
   766     rel ^ "(" ^ space_implode ", " (map write_term args) ^ "), Sols), writelist(Sols).\n" ^
   767     "writelist([]).\n" ^
   768     "writelist([(" ^ space_implode ", " vnames ^ ")|SolutionTail]) :- " ^
   769     "writef('" ^ space_implode ";" (map (fn v => v ^ " = %w") vnames) ^
   770     "\\n', [" ^ space_implode ", " vnames ^ "]), writelist(SolutionTail).\n"
   771 
   772 val swi_prolog_prelude =
   773   ":- use_module(library('dialect/ciao/aggregates')).\n" ^
   774   ":- style_check(-singleton).\n" ^
   775   ":- style_check(-discontiguous).\n" ^
   776   ":- style_check(-atom).\n\n" ^
   777   "main :- catch(eval, E, (print_message(error, E), fail)), halt.\n" ^
   778   "main :- halt(1).\n"
   779 
   780 
   781 (** query and prelude for yap **)
   782 
   783 fun yap_query_first (rel, args) vnames =
   784   "eval :- once(" ^ rel ^ "(" ^ space_implode ", " (map write_term args) ^ ")),\n" ^
   785   "format('" ^ space_implode ";" (map (fn v => v ^ " = ~w") vnames) ^
   786   "\\n', [" ^ space_implode ", " vnames ^ "]).\n"
   787 
   788 val yap_prelude =
   789   ":- initialization(eval).\n"
   790 
   791 
   792 (* system-dependent query, prelude and invocation *)
   793 
   794 fun query system nsols =
   795   (case system of
   796     SWI_PROLOG =>
   797       (case nsols of
   798         NONE => swi_prolog_query_first
   799       | SOME n => swi_prolog_query_firstn n)
   800   | YAP =>
   801       (case nsols of
   802         NONE => yap_query_first
   803       | SOME n =>
   804           error "No support for querying multiple solutions in the prolog system yap"))
   805 
   806 fun prelude system =
   807   (case system of
   808     SWI_PROLOG => swi_prolog_prelude
   809   | YAP => yap_prelude)
   810 
   811 fun invoke system file =
   812   let
   813     val (env_var, cmd) =
   814       (case system of
   815         SWI_PROLOG => ("ISABELLE_SWIPL", "\"$ISABELLE_SWIPL\" -q -t main -f ")
   816       | YAP => ("ISABELLE_YAP", "\"$ISABELLE_YAP\" -L "))
   817   in
   818     if getenv env_var = "" then
   819       (warning (env_var ^ " not set; could not execute code for " ^ string_of_system system); "")
   820     else
   821       (case Isabelle_System.bash_output (cmd ^ File.shell_path file) of
   822         (out, 0) => out
   823       | (_, rc) =>
   824           error ("Error caused by prolog system " ^ env_var ^
   825             ": return code " ^ string_of_int rc))
   826   end
   827 
   828 
   829 (* parsing prolog solution *)
   830 
   831 val scan_number =
   832   Scan.many1 Symbol.is_ascii_digit
   833 
   834 val scan_atom =
   835   Scan.many1
   836     (fn s => Symbol.is_ascii_lower s orelse Symbol.is_ascii_digit s orelse Symbol.is_ascii_quasi s)
   837 
   838 val scan_var =
   839   Scan.many1
   840     (fn s => Symbol.is_ascii_upper s orelse Symbol.is_ascii_digit s orelse Symbol.is_ascii_quasi s)
   841 
   842 fun dest_Char (Symbol.Char s) = s
   843 
   844 val string_of = implode o map (dest_Char o Symbol.decode)
   845 
   846 fun int_of_symbol_list xs = fold (fn x => fn s => s * 10 + (ord x - ord "0")) xs 0
   847 
   848 fun scan_terms xs = (((scan_term --| $$ ",") ::: scan_terms)
   849   || (scan_term >> single)) xs
   850 and scan_term xs =
   851   ((scan_number >> (Number o int_of_symbol_list))
   852   || (scan_var >> (Var o string_of))
   853   || ((scan_atom -- ($$ "(" |-- scan_terms --| $$ ")"))
   854     >> (fn (f, ts) => AppF (string_of f, ts)))
   855   || (scan_atom >> (Cons o string_of))) xs
   856 
   857 val parse_term = fst o Scan.finite Symbol.stopper
   858     (Scan.error (!! (fn _ => raise Fail "parsing prolog output failed")) scan_term)
   859   o raw_explode
   860 
   861 fun parse_solutions sol =
   862   let
   863     fun dest_eq s =
   864       (case space_explode "=" s of
   865         (l :: r :: []) => parse_term (unprefix " " r)
   866       | _ => raise Fail "unexpected equation in prolog output")
   867     fun parse_solution s = map dest_eq (space_explode ";" s)
   868     val sols = (case space_explode "\n" sol of [] => [] | s => fst (split_last s))
   869   in
   870     map parse_solution sols
   871   end
   872 
   873 
   874 (* calling external interpreter and getting results *)
   875 
   876 fun run ctxt p (query_rel, args) vnames nsols =
   877   let
   878     val timeout = get_prolog_timeout ctxt
   879     val system = get_prolog_system ctxt
   880     val renaming = fold mk_renaming (fold add_vars args vnames) []
   881     val vnames' = map (fn v => the (AList.lookup (op =) renaming v)) vnames
   882     val args' = map (rename_vars_term renaming) args
   883     val prog = prelude system ^ query system nsols (query_rel, args') vnames' ^ write_program p
   884     val _ = tracing ("Generated prolog program:\n" ^ prog)
   885     val solution = Timeout.apply timeout (fn prog =>
   886       Isabelle_System.with_tmp_file "prolog_file" "" (fn prolog_file =>
   887         (File.write prolog_file prog; invoke system prolog_file))) prog
   888     val _ = tracing ("Prolog returned solution(s):\n" ^ solution)
   889     val tss = parse_solutions solution
   890   in
   891     tss
   892   end
   893 
   894 
   895 (* restoring types in terms *)
   896 
   897 fun restore_term ctxt constant_table (Var s, T) = Free (s, T)
   898   | restore_term ctxt constant_table (Number n, @{typ "int"}) = HOLogic.mk_number @{typ "int"} n
   899   | restore_term ctxt constant_table (Number n, _) = raise (Fail "unexpected type for number")
   900   | restore_term ctxt constant_table (Cons s, T) = Const (restore_const constant_table s, T)
   901   | restore_term ctxt constant_table (AppF (f, args), T) =
   902       let
   903         val thy = Proof_Context.theory_of ctxt
   904         val c = restore_const constant_table f
   905         val cT = Sign.the_const_type thy c
   906         val (argsT, resT) = strip_type cT
   907         val subst = Sign.typ_match thy (resT, T) Vartab.empty
   908         val argsT' = map (Envir.subst_type subst) argsT
   909       in
   910         list_comb (Const (c, Envir.subst_type subst cT),
   911           map (restore_term ctxt constant_table) (args ~~ argsT'))
   912       end
   913 
   914 
   915 (* restore numerals in natural numbers *)
   916 
   917 fun restore_nat_numerals t =
   918   if fastype_of t = @{typ nat} andalso is_some (try HOLogic.dest_nat t) then
   919     HOLogic.mk_number @{typ nat} (HOLogic.dest_nat t)
   920   else
   921     (case t of
   922       t1 $ t2 => restore_nat_numerals t1 $ restore_nat_numerals t2
   923     | t => t)
   924 
   925 
   926 (* values command *)
   927 
   928 val preprocess_options = Predicate_Compile_Aux.Options {
   929   expected_modes = NONE,
   930   proposed_modes = [],
   931   proposed_names = [],
   932   show_steps = false,
   933   show_intermediate_results = false,
   934   show_proof_trace = false,
   935   show_modes = false,
   936   show_mode_inference = false,
   937   show_compilation = false,
   938   show_caught_failures = false,
   939   show_invalid_clauses = false,
   940   skip_proof = true,
   941   no_topmost_reordering = false,
   942   function_flattening = true,
   943   specialise = false,
   944   fail_safe_function_flattening = false,
   945   no_higher_order_predicate = [],
   946   inductify = false,
   947   detect_switches = true,
   948   smart_depth_limiting = true,
   949   compilation = Predicate_Compile_Aux.Pred
   950 }
   951 
   952 fun values ctxt soln t_compr =
   953   let
   954     val options = code_options_of (Proof_Context.theory_of ctxt)
   955     val split =
   956       (case t_compr of
   957         (Const (@{const_name Collect}, _) $ t) => t
   958       | _ => error ("Not a set comprehension: " ^ Syntax.string_of_term ctxt t_compr))
   959     val (body, Ts, fp) = HOLogic.strip_ptupleabs split
   960     val output_names = Name.variant_list (Term.add_free_names body [])
   961       (map (fn i => "x" ^ string_of_int i) (1 upto length Ts))
   962     val output_frees = rev (map2 (curry Free) output_names Ts)
   963     val body = subst_bounds (output_frees, body)
   964     val (pred as Const (name, T), all_args) =
   965       (case strip_comb body of
   966         (Const (name, T), all_args) => (Const (name, T), all_args)
   967       | (head, _) => error ("Not a constant: " ^ Syntax.string_of_term ctxt head))
   968     val _ = tracing "Preprocessing specification..."
   969     val T = Sign.the_const_type (Proof_Context.theory_of ctxt) name
   970     val t = Const (name, T)
   971     val thy' =
   972       Proof_Context.theory_of ctxt
   973       |> Predicate_Compile.preprocess preprocess_options t
   974     val ctxt' = Proof_Context.init_global thy'
   975     val _ = tracing "Generating prolog program..."
   976     val (p, constant_table) = generate (NONE, #ensure_groundness options) ctxt' name (* FIXME *)
   977       |> post_process ctxt' options name
   978     val constant_table' = declare_consts (fold Term.add_const_names all_args []) constant_table
   979     val args' = map (translate_term ctxt constant_table') all_args
   980     val _ = tracing "Running prolog program..."
   981     val tss = run ctxt p (translate_const constant_table' name, args') output_names soln
   982     val _ = tracing "Restoring terms..."
   983     val empty = Const(@{const_name bot}, fastype_of t_compr)
   984     fun mk_insert x S =
   985       Const (@{const_name "Set.insert"}, fastype_of x --> fastype_of S --> fastype_of S) $ x $ S
   986     fun mk_set_compr in_insert [] xs =
   987        rev ((Free ("dots", fastype_of t_compr)) ::  (* FIXME proper name!? *)
   988         (if null in_insert then xs else (fold mk_insert in_insert empty) :: xs))
   989       | mk_set_compr in_insert (t :: ts) xs =
   990         let
   991           val frees = Term.add_frees t []
   992         in
   993           if null frees then
   994             mk_set_compr (t :: in_insert) ts xs
   995           else
   996             let
   997               val uu as (uuN, uuT) =
   998                 singleton (Variable.variant_frees ctxt' [t]) ("uu", fastype_of t)
   999               val set_compr =
  1000                 HOLogic.mk_Collect (uuN, uuT,
  1001                   fold (fn (s, T) => fn t => HOLogic.mk_exists (s, T, t))
  1002                     frees (HOLogic.mk_conj (HOLogic.mk_eq (Free uu, t), @{term "True"})))
  1003             in
  1004               mk_set_compr [] ts
  1005                 (set_compr ::
  1006                   (if null in_insert then xs else (fold mk_insert in_insert empty) :: xs))
  1007             end
  1008         end
  1009   in
  1010     foldl1 (HOLogic.mk_binop @{const_name sup}) (mk_set_compr []
  1011       (map (fn ts => HOLogic.mk_tuple
  1012         (map (restore_nat_numerals o restore_term ctxt' constant_table) (ts ~~ Ts))) tss) [])
  1013   end
  1014 
  1015 fun values_cmd print_modes soln raw_t state =
  1016   let
  1017     val ctxt = Toplevel.context_of state
  1018     val t = Syntax.read_term ctxt raw_t
  1019     val t' = values ctxt soln t
  1020     val ty' = Term.type_of t'
  1021     val ctxt' = Variable.auto_fixes t' ctxt
  1022     val _ = tracing "Printing terms..."
  1023   in
  1024     Print_Mode.with_modes print_modes (fn () =>
  1025       Pretty.block [Pretty.quote (Syntax.pretty_term ctxt' t'), Pretty.fbrk,
  1026         Pretty.str "::", Pretty.brk 1, Pretty.quote (Syntax.pretty_typ ctxt' ty')]) ()
  1027   end |> Pretty.writeln
  1028 
  1029 
  1030 (* values command for Prolog queries *)
  1031 
  1032 val opt_print_modes =
  1033   Scan.optional (@{keyword "("} |-- Parse.!!! (Scan.repeat1 Parse.xname --| @{keyword ")"})) []
  1034 
  1035 val _ =
  1036   Outer_Syntax.command @{command_keyword values_prolog}
  1037     "enumerate and print comprehensions"
  1038     (opt_print_modes -- Scan.optional (Parse.nat >> SOME) NONE -- Parse.term
  1039      >> (fn ((print_modes, soln), t) => Toplevel.keep (values_cmd print_modes soln t)))
  1040 
  1041 
  1042 (* quickcheck generator *)
  1043 
  1044 (* FIXME: a small clone of Predicate_Compile_Quickcheck - maybe refactor out commons *)
  1045 
  1046 val active = Attrib.setup_config_bool @{binding quickcheck_prolog_active} (K true)
  1047 
  1048 fun test_term ctxt (t, eval_terms) =
  1049   let
  1050     val t' = fold_rev absfree (Term.add_frees t []) t
  1051     val options = code_options_of (Proof_Context.theory_of ctxt)
  1052     val thy = Proof_Context.theory_of ctxt
  1053     val ((((full_constname, constT), vs'), intro), thy1) =
  1054       Predicate_Compile_Aux.define_quickcheck_predicate t' thy
  1055     val thy2 =
  1056       Context.theory_map (Named_Theorems.add_thm @{named_theorems code_pred_def} intro) thy1
  1057     val thy3 = Predicate_Compile.preprocess preprocess_options (Const (full_constname, constT)) thy2
  1058     val ctxt' = Proof_Context.init_global thy3
  1059     val _ = tracing "Generating prolog program..."
  1060     val (p, constant_table) = generate (NONE, true) ctxt' full_constname
  1061       |> post_process ctxt' (set_ensure_groundness options) full_constname
  1062     val _ = tracing "Running prolog program..."
  1063     val tss =
  1064       run ctxt p (translate_const constant_table full_constname, map (Var o fst) vs')
  1065         (map fst vs') (SOME 1)
  1066     val _ = tracing "Restoring terms..."
  1067     val counterexample =
  1068       (case tss of
  1069         [ts] => SOME (map (restore_term ctxt' constant_table) (ts ~~ map snd vs'))
  1070       | _ => NONE)
  1071   in
  1072     Quickcheck.Result
  1073       {counterexample =
  1074         Option.map (pair true o curry (op ~~) (Term.add_free_names t [])) counterexample,
  1075        evaluation_terms = Option.map (K []) counterexample,
  1076        timings = [],
  1077        reports = []}
  1078   end
  1079 
  1080 fun test_goals ctxt _ insts goals =
  1081   let
  1082     val correct_inst_goals = Quickcheck_Common.instantiate_goals ctxt insts goals
  1083   in
  1084     Quickcheck_Common.collect_results (test_term ctxt) (maps (map snd) correct_inst_goals) []
  1085   end
  1086 
  1087 end