bulwahn@38073: (*  Title:      HOL/Tools/Predicate_Compile/code_prolog.ML
bulwahn@38073:     Author:     Lukas Bulwahn, TU Muenchen
bulwahn@38073: 
bulwahn@38073: Prototype of an code generator for logic programming languages (a.k.a. Prolog)
bulwahn@38073: *)
bulwahn@38073: 
bulwahn@38073: signature CODE_PROLOG =
bulwahn@38073: sig
bulwahn@38727:   type code_options = {ensure_groundness : bool}
bulwahn@38727:   val options : code_options ref
bulwahn@38727: 
bulwahn@38113:   datatype arith_op = Plus | Minus
bulwahn@38112:   datatype prol_term = Var of string | Cons of string | AppF of string * prol_term list
bulwahn@38113:     | Number of int | ArithOp of arith_op * prol_term list;
bulwahn@38113:   datatype prem = Conj of prem list
bulwahn@38113:     | Rel of string * prol_term list | NotRel of string * prol_term list
bulwahn@38113:     | Eq of prol_term * prol_term | NotEq of prol_term * prol_term
bulwahn@38727:     | ArithEq of prol_term * prol_term | NotArithEq of prol_term * prol_term
bulwahn@38727:     | Ground of string * typ;
bulwahn@38727: 
bulwahn@38079:   type clause = ((string * prol_term list) * prem);
bulwahn@38073:   type logic_program = clause list;
bulwahn@38079:   type constant_table = (string * string) list
bulwahn@38727:     
bulwahn@38727:   val generate : code_options -> Proof.context -> string list -> (logic_program * constant_table)
bulwahn@38079:   val write_program : logic_program -> string
bulwahn@38079:   val run : logic_program -> string -> string list -> int option -> prol_term list list
bulwahn@38073: 
bulwahn@38079:   val trace : bool Unsynchronized.ref
bulwahn@38073: end;
bulwahn@38073: 
bulwahn@38073: structure Code_Prolog : CODE_PROLOG =
bulwahn@38073: struct
bulwahn@38073: 
bulwahn@38079: (* diagnostic tracing *)
bulwahn@38079: 
bulwahn@38079: val trace = Unsynchronized.ref false
bulwahn@38079: 
bulwahn@38079: fun tracing s = if !trace then Output.tracing s else () 
bulwahn@38727: 
bulwahn@38727: (* code generation options *)
bulwahn@38727: 
bulwahn@38727: type code_options = {ensure_groundness : bool}
bulwahn@38727: 
bulwahn@38727: val options = Unsynchronized.ref {ensure_groundness = false};
bulwahn@38727: 
bulwahn@38073: (* general string functions *)
bulwahn@38073: 
bulwahn@38073: val first_upper = implode o nth_map 0 Symbol.to_ascii_upper o explode;
bulwahn@38073: val first_lower = implode o nth_map 0 Symbol.to_ascii_lower o explode;
bulwahn@38073: 
bulwahn@38073: (* internal program representation *)
bulwahn@38073: 
bulwahn@38113: datatype arith_op = Plus | Minus
bulwahn@38113: 
bulwahn@38112: datatype prol_term = Var of string | Cons of string | AppF of string * prol_term list
bulwahn@38113:   | Number of int | ArithOp of arith_op * prol_term list;
bulwahn@38113: 
bulwahn@38113: fun is_Var (Var _) = true
bulwahn@38113:   | is_Var _ = false
bulwahn@38113: 
bulwahn@38113: fun is_arith_term (Var _) = true
bulwahn@38113:   | is_arith_term (Number _) = true
bulwahn@38113:   | is_arith_term (ArithOp (_, operands)) = forall is_arith_term operands
bulwahn@38113:   | is_arith_term _ = false
bulwahn@38073: 
bulwahn@38081: fun string_of_prol_term (Var s) = "Var " ^ s
bulwahn@38075:   | string_of_prol_term (Cons s) = "Cons " ^ s
bulwahn@38075:   | string_of_prol_term (AppF (f, args)) = f ^ "(" ^ commas (map string_of_prol_term args) ^ ")" 
bulwahn@38112:   | string_of_prol_term (Number n) = "Number " ^ string_of_int n
bulwahn@38075: 
bulwahn@38113: datatype prem = Conj of prem list
bulwahn@38113:   | Rel of string * prol_term list | NotRel of string * prol_term list
bulwahn@38113:   | Eq of prol_term * prol_term | NotEq of prol_term * prol_term
bulwahn@38727:   | ArithEq of prol_term * prol_term | NotArithEq of prol_term * prol_term
bulwahn@38727:   | Ground of string * typ;
bulwahn@38727:   
bulwahn@38073: fun dest_Rel (Rel (c, ts)) = (c, ts)
bulwahn@38073:  
bulwahn@38079: type clause = ((string * prol_term list) * prem);
bulwahn@38073: 
bulwahn@38073: type logic_program = clause list;
bulwahn@38073: 
bulwahn@38073: (* translation from introduction rules to internal representation *)
bulwahn@38073: 
bulwahn@38079: (** constant table **)
bulwahn@38079: 
bulwahn@38079: type constant_table = (string * string) list
bulwahn@38079: 
bulwahn@38073: (* assuming no clashing *)
bulwahn@38079: fun mk_constant_table consts =
bulwahn@38079:   AList.make (first_lower o Long_Name.base_name) consts
bulwahn@38079: 
bulwahn@38079: fun declare_consts consts constant_table =
bulwahn@38079:   fold (fn c => AList.update (op =) (c, first_lower (Long_Name.base_name c))) consts constant_table
bulwahn@38079:   
bulwahn@38079: fun translate_const constant_table c =
bulwahn@38079:   case AList.lookup (op =) constant_table c of
bulwahn@38079:     SOME c' => c'
bulwahn@38079:   | NONE => error ("No such constant: " ^ c)
bulwahn@38073: 
bulwahn@38079: fun inv_lookup _ [] _ = NONE
bulwahn@38079:   | inv_lookup eq ((key, value)::xs) value' =
bulwahn@38079:       if eq (value', value) then SOME key
bulwahn@38079:       else inv_lookup eq xs value';
bulwahn@38079: 
bulwahn@38079: fun restore_const constant_table c =
bulwahn@38079:   case inv_lookup (op =) constant_table c of
bulwahn@38079:     SOME c' => c'
bulwahn@38079:   | NONE => error ("No constant corresponding to "  ^ c)
bulwahn@38727: 
bulwahn@38079: (** translation of terms, literals, premises, and clauses **)
bulwahn@38079: 
bulwahn@38113: fun translate_arith_const @{const_name "Groups.plus_class.plus"} = SOME Plus
bulwahn@38113:   | translate_arith_const @{const_name "Groups.minus_class.minus"} = SOME Minus
bulwahn@38113:   | translate_arith_const _ = NONE
bulwahn@38113: 
bulwahn@38079: fun translate_term ctxt constant_table t =
bulwahn@38112:   case try HOLogic.dest_number t of
bulwahn@38112:     SOME (@{typ "int"}, n) => Number n
bulwahn@38112:   | NONE =>
bulwahn@38112:       (case strip_comb t of
bulwahn@38112:         (Free (v, T), []) => Var v 
bulwahn@38112:       | (Const (c, _), []) => Cons (translate_const constant_table c)
bulwahn@38112:       | (Const (c, _), args) =>
bulwahn@38113:         (case translate_arith_const c of
bulwahn@38113:           SOME aop => ArithOp (aop, map (translate_term ctxt constant_table) args)
bulwahn@38113:         | NONE =>                                                             
bulwahn@38113:             AppF (translate_const constant_table c, map (translate_term ctxt constant_table) args))
bulwahn@38112:       | _ => error ("illegal term for translation: " ^ Syntax.string_of_term ctxt t))
bulwahn@38073: 
bulwahn@38079: fun translate_literal ctxt constant_table t =
bulwahn@38073:   case strip_comb t of
bulwahn@38079:     (Const (@{const_name "op ="}, _), [l, r]) =>
bulwahn@38113:       let
bulwahn@38113:         val l' = translate_term ctxt constant_table l
bulwahn@38113:         val r' = translate_term ctxt constant_table r
bulwahn@38113:       in
bulwahn@38113:         (if is_Var l' andalso is_arith_term r' then ArithEq else Eq) (l', r')
bulwahn@38113:       end
bulwahn@38079:   | (Const (c, _), args) =>
bulwahn@38079:       Rel (translate_const constant_table c, map (translate_term ctxt constant_table) args)
bulwahn@38073:   | _ => error ("illegal literal for translation: " ^ Syntax.string_of_term ctxt t)
bulwahn@38073: 
bulwahn@38073: fun NegRel_of (Rel lit) = NotRel lit
bulwahn@38073:   | NegRel_of (Eq eq) = NotEq eq
bulwahn@38113:   | NegRel_of (ArithEq eq) = NotArithEq eq
bulwahn@38113: 
bulwahn@38727: fun mk_groundness_prems t = map Ground (Term.add_frees t [])
bulwahn@38727:   
bulwahn@38727: fun translate_prem options ctxt constant_table t =  
bulwahn@38073:     case try HOLogic.dest_not t of
bulwahn@38727:       SOME t =>
bulwahn@38727:         if #ensure_groundness options then
bulwahn@38727:           Conj (mk_groundness_prems t @ [NegRel_of (translate_literal ctxt constant_table t)])
bulwahn@38727:         else
bulwahn@38727:           NegRel_of (translate_literal ctxt constant_table t)
bulwahn@38079:     | NONE => translate_literal ctxt constant_table t
bulwahn@38114:     
bulwahn@38114: fun imp_prems_conv cv ct =
bulwahn@38114:   case Thm.term_of ct of
bulwahn@38114:     Const ("==>", _) $ _ $ _ => Conv.combination_conv (Conv.arg_conv cv) (imp_prems_conv cv) ct
bulwahn@38114:   | _ => Conv.all_conv ct
bulwahn@38114: 
bulwahn@38114: fun Trueprop_conv cv ct =
bulwahn@38114:   case Thm.term_of ct of
haftmann@38558:     Const (@{const_name Trueprop}, _) $ _ => Conv.arg_conv cv ct  
bulwahn@38114:   | _ => raise Fail "Trueprop_conv"
bulwahn@38114: 
bulwahn@38114: fun preprocess_intro thy rule =
bulwahn@38114:   Conv.fconv_rule
bulwahn@38114:     (imp_prems_conv
bulwahn@38114:       (Trueprop_conv (Conv.try_conv (Conv.rewr_conv @{thm Predicate.eq_is_eq}))))
bulwahn@38114:     (Thm.transfer thy rule)
bulwahn@38114: 
bulwahn@38727: fun translate_intros options ctxt gr const constant_table =
bulwahn@38073:   let
bulwahn@38114:     val intros = map (preprocess_intro (ProofContext.theory_of ctxt)) (Graph.get_node gr const)
bulwahn@38073:     val (intros', ctxt') = Variable.import_terms true (map prop_of intros) ctxt
bulwahn@38079:     val constant_table' = declare_consts (fold Term.add_const_names intros' []) constant_table
bulwahn@38073:     fun translate_intro intro =
bulwahn@38073:       let
bulwahn@38073:         val head = HOLogic.dest_Trueprop (Logic.strip_imp_concl intro)
bulwahn@38727:         val prems = map HOLogic.dest_Trueprop (Logic.strip_imp_prems intro)
bulwahn@38727:         val prems' = Conj (map (translate_prem options ctxt' constant_table') prems)
bulwahn@38079:         val clause = (dest_Rel (translate_literal ctxt' constant_table' head), prems')
bulwahn@38073:       in clause end
bulwahn@38079:   in (map translate_intro intros', constant_table') end
bulwahn@38073: 
bulwahn@38727: fun generate options ctxt const =
bulwahn@38073:   let 
bulwahn@38073:      fun strong_conn_of gr keys =
bulwahn@38073:       Graph.strong_conn (Graph.subgraph (member (op =) (Graph.all_succs gr keys)) gr)
bulwahn@38073:     val gr = Predicate_Compile_Core.intros_graph_of ctxt
bulwahn@38073:     val scc = strong_conn_of gr const
bulwahn@38079:     val constant_table = mk_constant_table (flat scc)
bulwahn@38073:   in
bulwahn@38727:     apfst flat (fold_map (translate_intros options ctxt gr) (flat scc) constant_table)
bulwahn@38073:   end
bulwahn@38727:   
bulwahn@38727: (* add implementation for ground predicates *)
bulwahn@38073: 
bulwahn@38727: fun add_ground_typ (Conj prems) = fold add_ground_typ prems
bulwahn@38727:   | add_ground_typ (Ground (_, T)) = insert (op =) T
bulwahn@38727:   | add_ground_typ _ = I
bulwahn@38073: 
bulwahn@38727: fun mk_ground_impl ctxt (Type (Tcon, [])) constant_table =
bulwahn@38073:   let
bulwahn@38727:     fun mk_impl (constr_name, T) constant_table =
bulwahn@38727:       if binder_types T = [] then
bulwahn@38727:         let
bulwahn@38727:           val constant_table' = declare_consts [constr_name] constant_table
bulwahn@38727:           val clause = (("is_" ^ first_lower (Long_Name.base_name Tcon),
bulwahn@38727:             [Cons (translate_const constant_table' constr_name)]), Conj [])
bulwahn@38727:         in
bulwahn@38727:           (clause, constant_table')
bulwahn@38727:         end
bulwahn@38727:         else raise Fail "constructor with arguments" 
bulwahn@38727:     val constrs = the (Datatype.get_constrs (ProofContext.theory_of ctxt) Tcon)
bulwahn@38727:   in fold_map mk_impl constrs constant_table end
bulwahn@38727:   | mk_ground_impl ctxt (Type (Tcon, _)) constant_table =
bulwahn@38727:     raise Fail "type constructor with type arguments"
bulwahn@38727:   
bulwahn@38727: fun replace_ground (Conj prems) = Conj (map replace_ground prems)
bulwahn@38727:   | replace_ground (Ground (x, Type (Tcon, []))) =
bulwahn@38727:     Rel ("is_" ^ first_lower (Long_Name.base_name Tcon), [Var x])  
bulwahn@38727:   | replace_ground p = p
bulwahn@38727:   
bulwahn@38727: fun add_ground_predicates ctxt (p, constant_table) =
bulwahn@38727:   let
bulwahn@38727:     val ground_typs = fold (add_ground_typ o snd) p []
bulwahn@38727:     val (grs, constant_table') = fold_map (mk_ground_impl ctxt) ground_typs constant_table
bulwahn@38727:     val p' = map (apsnd replace_ground) p
bulwahn@38073:   in
bulwahn@38727:     ((flat grs) @ p', constant_table')
bulwahn@38073:   end
bulwahn@38727:     
bulwahn@38073: (* code printer *)
bulwahn@38073: 
bulwahn@38113: fun write_arith_op Plus = "+"
bulwahn@38113:   | write_arith_op Minus = "-"
bulwahn@38113: 
bulwahn@38081: fun write_term (Var v) = first_upper v
bulwahn@38079:   | write_term (Cons c) = c
bulwahn@38113:   | write_term (AppF (f, args)) = f ^ "(" ^ space_implode ", " (map write_term args) ^ ")"
bulwahn@38113:   | write_term (ArithOp (oper, [a1, a2])) = write_term a1 ^ " " ^ write_arith_op oper ^ " " ^ write_term a2
bulwahn@38112:   | write_term (Number n) = string_of_int n
bulwahn@38073: 
bulwahn@38073: fun write_rel (pred, args) =
bulwahn@38073:   pred ^ "(" ^ space_implode ", " (map write_term args) ^ ")" 
bulwahn@38073: 
bulwahn@38073: fun write_prem (Conj prems) = space_implode ", " (map write_prem prems)
bulwahn@38073:   | write_prem (Rel p) = write_rel p  
bulwahn@38073:   | write_prem (NotRel p) = "not(" ^ write_rel p ^ ")"
bulwahn@38073:   | write_prem (Eq (l, r)) = write_term l ^ " = " ^ write_term r
bulwahn@38073:   | write_prem (NotEq (l, r)) = write_term l ^ " \\= " ^ write_term r
bulwahn@38113:   | write_prem (ArithEq (l, r)) = write_term l ^ " is " ^ write_term r
bulwahn@38113:   | write_prem (NotArithEq (l, r)) = write_term l ^ " =\\= " ^ write_term r
bulwahn@38073: 
bulwahn@38073: fun write_clause (head, prem) =
bulwahn@38073:   write_rel head ^ (if prem = Conj [] then "." else " :- " ^ write_prem prem ^ ".")
bulwahn@38073: 
bulwahn@38073: fun write_program p =
bulwahn@38073:   cat_lines (map write_clause p) 
bulwahn@38073: 
bulwahn@38078: (** query templates **)
bulwahn@38078: 
bulwahn@38073: fun query_first rel vnames =
bulwahn@38073:   "eval :- once("  ^ rel ^ "(" ^ space_implode ", " vnames ^ ")),\n" ^
bulwahn@38082:   "writef('" ^ space_implode ";" (map (fn v => v ^ " = %w") vnames) ^
bulwahn@38082:   "\\n', [" ^ space_implode ", " vnames ^ "]).\n"
bulwahn@38077:   
bulwahn@38077: fun query_firstn n rel vnames =
bulwahn@38077:   "eval :- findnsols(" ^ string_of_int n ^ ", (" ^ space_implode ", " vnames ^ "), " ^
bulwahn@38077:     rel ^ "(" ^ space_implode ", " vnames ^ "), Sols), writelist(Sols).\n" ^
bulwahn@38077:     "writelist([]).\n" ^
bulwahn@38077:     "writelist([(" ^ space_implode ", " vnames ^ ")|T]) :- " ^
bulwahn@38079:     "writef('" ^ space_implode ";" (map (fn v => v ^ " = %w") vnames) ^
bulwahn@38079:     "\\n', [" ^ space_implode ", " vnames ^ "]), writelist(T).\n"
bulwahn@38077:   
bulwahn@38073: val prelude =
bulwahn@38073:   "#!/usr/bin/swipl -q -t main -f\n\n" ^
bulwahn@38077:   ":- use_module(library('dialect/ciao/aggregates')).\n" ^
bulwahn@38073:   ":- style_check(-singleton).\n\n" ^
bulwahn@38073:   "main :- catch(eval, E, (print_message(error, E), fail)), halt.\n" ^
bulwahn@38073:   "main :- halt(1).\n"
bulwahn@38075: 
bulwahn@38075: (* parsing prolog solution *)
bulwahn@38115: val scan_number =
bulwahn@38115:   Scan.many1 Symbol.is_ascii_digit
bulwahn@38075: 
bulwahn@38075: val scan_atom =
bulwahn@38078:   Scan.many1 (fn s => Symbol.is_ascii_lower s orelse Symbol.is_ascii_quasi s)
bulwahn@38075: 
bulwahn@38075: val scan_var =
bulwahn@38078:   Scan.many1
bulwahn@38078:     (fn s => Symbol.is_ascii_upper s orelse Symbol.is_ascii_digit s orelse Symbol.is_ascii_quasi s)
bulwahn@38075: 
bulwahn@38076: val scan_ident =
bulwahn@38076:   Scan.repeat (Scan.one
bulwahn@38076:     (fn s => Symbol.is_ascii_letter s orelse Symbol.is_ascii_digit s orelse Symbol.is_ascii_quasi s))
bulwahn@38076: 
bulwahn@38075: fun dest_Char (Symbol.Char s) = s
bulwahn@38075: 
bulwahn@38075: val string_of = concat o map (dest_Char o Symbol.decode)
bulwahn@38075: 
bulwahn@38076: val is_atom_ident = forall Symbol.is_ascii_lower
bulwahn@38076: 
bulwahn@38076: val is_var_ident =
bulwahn@38076:   forall (fn s => Symbol.is_ascii_upper s orelse Symbol.is_ascii_digit s orelse Symbol.is_ascii_quasi s)
bulwahn@38078: 
bulwahn@38115: fun int_of_symbol_list xs = fold (fn x => fn s => s * 10 + (ord x - ord "0")) xs 0
bulwahn@38115: 
bulwahn@38078: fun scan_terms xs = (((scan_term --| $$ ",") ::: scan_terms)
bulwahn@38078:   || (scan_term >> single)) xs
bulwahn@38078: and scan_term xs =
bulwahn@38115:   ((scan_number >> (Number o int_of_symbol_list))
bulwahn@38115:   || (scan_var >> (Var o string_of))
bulwahn@38078:   || ((scan_atom -- ($$ "(" |-- scan_terms --| $$ ")"))
bulwahn@38079:     >> (fn (f, ts) => AppF (string_of f, ts)))
bulwahn@38078:   || (scan_atom >> (Cons o string_of))) xs
bulwahn@38079: 
bulwahn@38075: val parse_term = fst o Scan.finite Symbol.stopper
bulwahn@38077:     (Scan.error (!! (fn _ => raise Fail "parsing prolog output failed")) scan_term)
bulwahn@38075:   o explode
bulwahn@38075:   
bulwahn@38079: fun parse_solutions sol =
bulwahn@38075:   let
bulwahn@38077:     fun dest_eq s = case space_explode "=" s of
bulwahn@38075:         (l :: r :: []) => parse_term (unprefix " " r)
bulwahn@38078:       | _ => raise Fail "unexpected equation in prolog output"
bulwahn@38079:     fun parse_solution s = map dest_eq (space_explode ";" s)
bulwahn@38075:   in
bulwahn@38079:     map parse_solution (fst (split_last (space_explode "\n" sol)))
bulwahn@38075:   end 
bulwahn@38073:   
bulwahn@38073: (* calling external interpreter and getting results *)
bulwahn@38073: 
bulwahn@38077: fun run p query_rel vnames nsols =
bulwahn@38073:   let
bulwahn@38073:     val cmd = Path.named_root
bulwahn@38077:     val query = case nsols of NONE => query_first | SOME n => query_firstn n 
bulwahn@38077:     val prog = prelude ^ query query_rel vnames ^ write_program p
bulwahn@38079:     val _ = tracing ("Generated prolog program:\n" ^ prog)
bulwahn@38073:     val prolog_file = File.tmp_path (Path.basic "prolog_file")
bulwahn@38073:     val _ = File.write prolog_file prog
bulwahn@38077:     val (solution, _) = bash_output ("/usr/local/bin/swipl -f " ^ File.shell_path prolog_file)
bulwahn@38079:     val _ = tracing ("Prolog returned solution(s):\n" ^ solution)
bulwahn@38079:     val tss = parse_solutions solution
bulwahn@38073:   in
bulwahn@38079:     tss
bulwahn@38073:   end
bulwahn@38073: 
bulwahn@38075: (* values command *)
bulwahn@38075: 
bulwahn@38081: fun restore_term ctxt constant_table (Var s, T) = Free (s, T)
bulwahn@38115:   | restore_term ctxt constant_table (Number n, @{typ "int"}) = HOLogic.mk_number @{typ "int"} n
bulwahn@38115:   | restore_term ctxt constant_table (Number n, _) = raise (Fail "unexpected type for number") 
bulwahn@38079:   | restore_term ctxt constant_table (Cons s, T) = Const (restore_const constant_table s, T)
bulwahn@38079:   | restore_term ctxt constant_table (AppF (f, args), T) =
bulwahn@38079:     let
bulwahn@38079:       val thy = ProofContext.theory_of ctxt
bulwahn@38079:       val c = restore_const constant_table f
bulwahn@38079:       val cT = Sign.the_const_type thy c
bulwahn@38079:       val (argsT, resT) = strip_type cT
bulwahn@38079:       val subst = Sign.typ_match thy (resT, T) Vartab.empty
bulwahn@38079:       val argsT' = map (Envir.subst_type subst) argsT
bulwahn@38079:     in
bulwahn@38079:       list_comb (Const (c, Envir.subst_type subst cT),
bulwahn@38079:         map (restore_term ctxt constant_table) (args ~~ argsT'))
bulwahn@38079:     end
bulwahn@38079: 
bulwahn@38075: fun values ctxt soln t_compr =
bulwahn@38075:   let
bulwahn@38727:     val options = !options
bulwahn@38075:     val split = case t_compr of (Const (@{const_name Collect}, _) $ t) => t
bulwahn@38075:       | _ => error ("Not a set comprehension: " ^ Syntax.string_of_term ctxt t_compr);
bulwahn@38075:     val (body, Ts, fp) = HOLogic.strip_psplits split;
bulwahn@38075:     val output_names = Name.variant_list (Term.add_free_names body [])
bulwahn@38075:       (map (fn i => "x" ^ string_of_int i) (1 upto length Ts))
bulwahn@38080:     val output_frees = rev (map2 (curry Free) output_names Ts)
bulwahn@38075:     val body = subst_bounds (output_frees, body)
bulwahn@38075:     val (pred as Const (name, T), all_args) =
bulwahn@38075:       case strip_comb body of
bulwahn@38075:         (Const (name, T), all_args) => (Const (name, T), all_args)
bulwahn@38075:       | (head, _) => error ("Not a constant: " ^ Syntax.string_of_term ctxt head)
bulwahn@38075:     val vnames =
bulwahn@38075:       case try (map (fst o dest_Free)) all_args of
bulwahn@38075:         SOME vs => vs
bulwahn@38075:       | NONE => error ("Not only free variables in " ^ commas (map (Syntax.string_of_term ctxt) all_args))
bulwahn@38079:     val _ = tracing "Generating prolog program..."
bulwahn@38727:     val (p, constant_table) = generate options ctxt [name]
bulwahn@38727:       |> (if #ensure_groundness options then add_ground_predicates ctxt else I)
bulwahn@38079:     val _ = tracing "Running prolog program..."
bulwahn@38079:     val tss = run p (translate_const constant_table name) (map first_upper vnames) soln
bulwahn@38079:     val _ = tracing "Restoring terms..."
bulwahn@38115:     val empty = Const("Orderings.bot_class.bot", fastype_of t_compr)
bulwahn@38115:     fun mk_insert x S =
bulwahn@38115:       Const (@{const_name "Set.insert"}, fastype_of x --> fastype_of S --> fastype_of S) $ x $ S 
bulwahn@38115:     fun mk_set_compr in_insert [] xs =
bulwahn@38115:        rev ((Free ("...", fastype_of t_compr)) ::
bulwahn@38115:         (if null in_insert then xs else (fold mk_insert in_insert empty) :: xs))
bulwahn@38115:       | mk_set_compr in_insert (t :: ts) xs =
bulwahn@38115:         let
bulwahn@38115:           val frees = Term.add_frees t []
bulwahn@38115:         in
bulwahn@38115:           if null frees then
bulwahn@38115:             mk_set_compr (t :: in_insert) ts xs
bulwahn@38115:           else
bulwahn@38115:             let
bulwahn@38115:               val uu as (uuN, uuT) = singleton (Variable.variant_frees ctxt [t]) ("uu", fastype_of t)
bulwahn@38115:               val set_compr =
bulwahn@38115:                 HOLogic.mk_Collect (uuN, uuT, fold (fn (s, T) => fn t => HOLogic.mk_exists (s, T, t))
bulwahn@38115:                   frees (HOLogic.mk_conj (HOLogic.mk_eq (Free uu, t), @{term "True"})))
bulwahn@38115:             in
bulwahn@38115:               set_compr :: (if null in_insert then xs else (fold mk_insert in_insert empty) :: xs)  
bulwahn@38115:             end
bulwahn@38115:         end
bulwahn@38075:   in
bulwahn@38115:       foldl1 (HOLogic.mk_binop @{const_name sup}) (mk_set_compr []
bulwahn@38115:         (map (fn ts => HOLogic.mk_tuple (map (restore_term ctxt constant_table) (ts ~~ Ts))) tss) [])
bulwahn@38075:   end
bulwahn@38075: 
bulwahn@38075: fun values_cmd print_modes soln raw_t state =
bulwahn@38075:   let
bulwahn@38075:     val ctxt = Toplevel.context_of state
bulwahn@38075:     val t = Syntax.read_term ctxt raw_t
bulwahn@38075:     val t' = values ctxt soln t
bulwahn@38075:     val ty' = Term.type_of t'
bulwahn@38075:     val ctxt' = Variable.auto_fixes t' ctxt
bulwahn@38115:     val _ = tracing "Printing terms..."
bulwahn@38075:     val p = Print_Mode.with_modes print_modes (fn () =>
bulwahn@38075:       Pretty.block [Pretty.quote (Syntax.pretty_term ctxt' t'), Pretty.fbrk,
bulwahn@38075:         Pretty.str "::", Pretty.brk 1, Pretty.quote (Syntax.pretty_typ ctxt' ty')]) ();
bulwahn@38075:   in Pretty.writeln p end;
bulwahn@38075: 
bulwahn@38075: 
bulwahn@38075: (* renewing the values command for Prolog queries *)
bulwahn@38075: 
bulwahn@38075: val opt_print_modes =
bulwahn@38075:   Scan.optional (Parse.$$$ "(" |-- Parse.!!! (Scan.repeat1 Parse.xname --| Parse.$$$ ")")) [];
bulwahn@38075: 
bulwahn@38075: val _ = Outer_Syntax.improper_command "values" "enumerate and print comprehensions" Keyword.diag
bulwahn@38077:   (opt_print_modes -- Scan.optional (Parse.nat >> SOME) NONE -- Parse.term
bulwahn@38075:    >> (fn ((print_modes, soln), t) => Toplevel.keep
haftmann@38504:         (values_cmd print_modes soln t))); (*FIXME does not preserve the previous functionality*)
bulwahn@38075: 
bulwahn@38073: end;