src/Pure/sign.ML
author wenzelm
Mon Nov 09 15:40:26 1998 +0100 (1998-11-09)
changeset 5838 a4122945d638
parent 5642 1b3e48bdbb93
child 6040 bd37dc0f56d9
permissions -rw-r--r--
added metacuts_tac;
     1 (*  Title:      Pure/sign.ML
     2     ID:         $Id$
     3     Author:     Lawrence C Paulson and Markus Wenzel
     4 
     5 The abstract type "sg" of signatures.
     6 *)
     7 
     8 (*base names*)
     9 type bstring = string;
    10 type bclass = class;
    11 (*external forms -- partially qualified names*)
    12 type xstring = string;
    13 type xclass = class;
    14 type xsort = sort;
    15 type xtyp = typ;
    16 type xterm = term;
    17 
    18 signature SIGN =
    19 sig
    20   type sg
    21   type sg_ref
    22   type data
    23   val rep_sg: sg ->
    24    {self: sg_ref,
    25     tsig: Type.type_sig,
    26     const_tab: typ Symtab.table,
    27     syn: Syntax.syntax,
    28     path: string list,
    29     spaces: (string * NameSpace.T) list,
    30     data: data}
    31   val name_of: sg -> string
    32   val stamp_names_of: sg -> string list
    33   val tsig_of: sg -> Type.type_sig
    34   val deref: sg_ref -> sg
    35   val self_ref: sg -> sg_ref
    36   val subsig: sg * sg -> bool
    37   val eq_sg: sg * sg -> bool
    38   val same_sg: sg * sg -> bool
    39   val is_draft: sg -> bool
    40   val is_stale: sg -> bool
    41   val const_type: sg -> string -> typ option
    42   val classes: sg -> class list
    43   val defaultS: sg -> sort
    44   val subsort: sg -> sort * sort -> bool
    45   val nodup_Vars: term -> unit
    46   val norm_sort: sg -> sort -> sort
    47   val nonempty_sort: sg -> sort list -> sort -> bool
    48   val of_sort: sg -> typ * sort -> bool
    49   val classK: string
    50   val typeK: string
    51   val constK: string
    52   val full_name: sg -> bstring -> string
    53   val full_name_path: sg -> string -> bstring -> string
    54   val base_name: string -> bstring
    55   val intern: sg -> string -> xstring -> string
    56   val extern: sg -> string -> string -> xstring
    57   val cond_extern: sg -> string -> string -> xstring
    58   val intern_class: sg -> xclass -> class
    59   val intern_tycon: sg -> xstring -> string
    60   val intern_const: sg -> xstring -> string
    61   val intern_sort: sg -> xsort -> sort
    62   val intern_typ: sg -> xtyp -> typ
    63   val intern_term: sg -> xterm -> term
    64   val intern_tycons: sg -> xtyp -> typ
    65   val pretty_sg: sg -> Pretty.T
    66   val str_of_sg: sg -> string
    67   val pprint_sg: sg -> pprint_args -> unit
    68   val pretty_term: sg -> term -> Pretty.T
    69   val pretty_typ: sg -> typ -> Pretty.T
    70   val pretty_sort: sg -> sort -> Pretty.T
    71   val pretty_classrel: sg -> class * class -> Pretty.T
    72   val pretty_arity: sg -> string * sort list * sort -> Pretty.T
    73   val string_of_term: sg -> term -> string
    74   val string_of_typ: sg -> typ -> string
    75   val string_of_sort: sg -> sort -> string
    76   val str_of_sort: sg -> sort -> string
    77   val str_of_classrel: sg -> class * class -> string
    78   val str_of_arity: sg -> string * sort list * sort -> string
    79   val pprint_term: sg -> term -> pprint_args -> unit
    80   val pprint_typ: sg -> typ -> pprint_args -> unit
    81   val certify_typ: sg -> typ -> typ
    82   val certify_term: sg -> term -> term * typ * int
    83   val read_raw_typ: sg * (indexname -> sort option) -> string -> typ
    84   val read_typ: sg * (indexname -> sort option) -> string -> typ
    85   val infer_types: sg -> (indexname -> typ option) ->
    86     (indexname -> sort option) -> string list -> bool
    87     -> xterm list * typ -> term * (indexname * typ) list
    88   val infer_types_simult: sg -> (indexname -> typ option) ->
    89     (indexname -> sort option) -> string list -> bool
    90     -> (xterm list * typ) list -> term list * (indexname * typ) list
    91   val add_classes: (bclass * xclass list) list -> sg -> sg
    92   val add_classes_i: (bclass * class list) list -> sg -> sg
    93   val add_classrel: (xclass * xclass) list -> sg -> sg
    94   val add_classrel_i: (class * class) list -> sg -> sg
    95   val add_defsort: xsort -> sg -> sg
    96   val add_defsort_i: sort -> sg -> sg
    97   val add_types: (bstring * int * mixfix) list -> sg -> sg
    98   val add_nonterminals: bstring list -> sg -> sg
    99   val add_tyabbrs: (bstring * string list * string * mixfix) list -> sg -> sg
   100   val add_tyabbrs_i: (bstring * string list * typ * mixfix) list -> sg -> sg
   101   val add_arities: (xstring * xsort list * xsort) list -> sg -> sg
   102   val add_arities_i: (string * sort list * sort) list -> sg -> sg
   103   val add_consts: (bstring * string * mixfix) list -> sg -> sg
   104   val add_consts_i: (bstring * typ * mixfix) list -> sg -> sg
   105   val add_syntax: (bstring * string * mixfix) list -> sg -> sg
   106   val add_syntax_i: (bstring * typ * mixfix) list -> sg -> sg
   107   val add_modesyntax: (string * bool) * (bstring * string * mixfix) list -> sg -> sg
   108   val add_modesyntax_i: (string * bool) * (bstring * typ * mixfix) list -> sg -> sg
   109   val add_trfuns:
   110     (string * (ast list -> ast)) list *
   111     (string * (term list -> term)) list *
   112     (string * (term list -> term)) list *
   113     (string * (ast list -> ast)) list -> sg -> sg
   114   val add_trfunsT:
   115     (string * (bool -> typ -> term list -> term)) list -> sg -> sg
   116   val add_tokentrfuns:
   117     (string * string * (string -> string * int)) list -> sg -> sg
   118   val add_trrules: (xstring * string) Syntax.trrule list -> sg -> sg
   119   val add_trrules_i: ast Syntax.trrule list -> sg -> sg
   120   val add_path: string -> sg -> sg
   121   val add_space: string * string list -> sg -> sg
   122   val add_name: string -> sg -> sg
   123   val data_kinds: data -> string list
   124   val merge_refs: sg_ref * sg_ref -> sg_ref
   125   val merge: sg * sg -> sg
   126   val prep_ext: sg -> sg
   127   val nontriv_merge: sg * sg -> sg
   128   val pre_pure: sg
   129   val const_of_class: class -> string
   130   val class_of_const: string -> class
   131 end;
   132 
   133 signature SIGN_PRIVATE =
   134 sig
   135   include SIGN
   136   val init_data: Object.kind * (Object.T * (Object.T -> Object.T) *
   137     (Object.T * Object.T -> Object.T) * (sg -> Object.T -> unit)) -> sg -> sg
   138   val get_data: Object.kind -> (Object.T -> 'a) -> sg -> 'a
   139   val put_data: Object.kind -> ('a -> Object.T) -> 'a -> sg -> sg
   140   val print_data: Object.kind -> sg -> unit
   141 end;
   142 
   143 structure Sign: SIGN_PRIVATE =
   144 struct
   145 
   146 
   147 (** datatype sg **)
   148 
   149 (* types sg, data, sg_ref *)
   150 
   151 datatype sg =
   152   Sg of
   153    {id: string ref,                             (*id*)
   154     stamps: string ref list} *                  (*unique theory indentifier*)
   155    {self: sg_ref,                               (*mutable self reference*)
   156     tsig: Type.type_sig,                        (*order-sorted signature of types*)
   157     const_tab: typ Symtab.table,                (*type schemes of constants*)
   158     syn: Syntax.syntax,                         (*syntax for parsing and printing*)
   159     path: string list,                          (*current name space entry prefix*)
   160     spaces: (string * NameSpace.T) list,        (*name spaces for consts, types etc.*)
   161     data: data}                                 (*anytype data*)
   162 and data =
   163   Data of
   164     (Object.kind *				(*kind (for authorization)*)
   165       (Object.T *				(*value*)
   166         ((Object.T -> Object.T) *               (*prepare extend method*)
   167           (Object.T * Object.T -> Object.T) *   (*merge and prepare extend method*)
   168           (sg -> Object.T -> unit))))           (*print method*)
   169     Symtab.table
   170 and sg_ref =
   171   SgRef of sg ref option;
   172 
   173 (*make signature*)
   174 fun make_sign (id, self, tsig, const_tab, syn, path, spaces, data, stamps) =
   175   Sg ({id = id, stamps = stamps}, {self = self, tsig = tsig, const_tab = const_tab,
   176     syn = syn, path = path, spaces = spaces, data = data});
   177 
   178 
   179 (* basic operations *)
   180 
   181 fun rep_sg (Sg (_, args)) = args;
   182 
   183 (*show stamps*)
   184 fun stamp_names_of (Sg ({stamps, ...}, _)) = rev (map ! stamps);
   185 fun pretty_sg sg = Pretty.str_list "{" "}" (stamp_names_of sg);
   186 val str_of_sg = Pretty.str_of o pretty_sg;
   187 val pprint_sg = Pretty.pprint o pretty_sg;
   188 
   189 val tsig_of = #tsig o rep_sg;
   190 
   191 fun const_type (Sg (_, {const_tab, ...})) c = Symtab.lookup (const_tab, c);
   192 
   193 
   194 (* id and self *)
   195 
   196 fun check_stale (sg as Sg ({id, ...},
   197         {self = SgRef (Some (ref (Sg ({id = id', ...}, _)))), ...})) =
   198       if id = id' then sg
   199       else raise TERM ("Stale signature: " ^ str_of_sg sg, [])
   200   | check_stale _ = sys_error "Sign.check_stale";
   201 
   202 fun is_stale sg = (check_stale sg; false) handle TERM _ => true;
   203 
   204 fun self_ref (sg as Sg (_, {self, ...})) = (check_stale sg; self);
   205 
   206 fun deref (SgRef (Some (ref sg))) = sg
   207   | deref (SgRef None) = sys_error "Sign.deref";
   208 
   209 fun name_of (sg as Sg ({id = ref name, ...}, _)) =
   210   if name = "" orelse ord name = ord "#" then
   211     raise TERM ("Nameless signature " ^ str_of_sg sg, [])
   212   else name;
   213 
   214 
   215 (* inclusion and equality *)
   216 
   217 local
   218   (*avoiding polymorphic equality: factor 10 speedup*)
   219   fun mem_stamp (_:string ref, []) = false
   220     | mem_stamp (x, y :: ys) = x = y orelse mem_stamp (x, ys);
   221 
   222   fun subset_stamp ([], ys) = true
   223     | subset_stamp (x :: xs, ys) =
   224         mem_stamp (x, ys) andalso subset_stamp (xs, ys);
   225 
   226   (*fast partial test*)
   227   fun fast_sub ([]: string ref list, _) = true
   228     | fast_sub (_, []) = false
   229     | fast_sub (x :: xs, y :: ys) =
   230         if x = y then fast_sub (xs, ys)
   231         else fast_sub (x :: xs, ys);
   232 in
   233   fun eq_sg (sg1 as Sg ({id = id1, ...}, _), sg2 as Sg ({id = id2, ...}, _)) =
   234     (check_stale sg1; check_stale sg2; id1 = id2);
   235 
   236   fun subsig (sg1 as Sg ({stamps = s1, ...}, _), sg2 as Sg ({stamps = s2, ...}, _)) =
   237     eq_sg (sg1, sg2) orelse subset_stamp (s1, s2);
   238 
   239   fun fast_subsig (sg1 as Sg ({stamps = s1, ...}, _), sg2 as Sg ({stamps = s2, ...}, _)) =
   240     eq_sg (sg1, sg2) orelse fast_sub (s1, s2);
   241 end;
   242 
   243 
   244 (*test if same theory names are contained in signatures' stamps,
   245   i.e. if signatures belong to same theory but not necessarily to the
   246   same version of it*)
   247 fun same_sg (sg1 as Sg ({stamps = s1, ...}, _), sg2 as Sg ({stamps = s2, ...}, _)) =
   248   eq_sg (sg1, sg2) orelse eq_set_string (pairself (map (op !)) (s1, s2));
   249 
   250 (*test for drafts*)
   251 fun is_draft (Sg ({stamps = ref name :: _, ...}, _)) = name = "" orelse ord name = ord "#";
   252 
   253 
   254 (* classes and sorts *)
   255 
   256 val classes = #classes o Type.rep_tsig o tsig_of;
   257 
   258 val defaultS = Type.defaultS o tsig_of;
   259 val subsort = Type.subsort o tsig_of;
   260 val norm_sort = Type.norm_sort o tsig_of;
   261 val nonempty_sort = Type.nonempty_sort o tsig_of;
   262 
   263 fun of_sort (Sg (_, {tsig, ...})) =
   264   Sorts.of_sort (#classrel (Type.rep_tsig tsig)) (#arities (Type.rep_tsig tsig));
   265 
   266 
   267 
   268 (** signature data **)
   269 
   270 (* errors *)
   271 
   272 fun of_theory sg = "\nof theory " ^ str_of_sg sg;
   273 
   274 fun err_inconsistent kinds =
   275   error ("Attempt to merge different versions of " ^ commas_quote kinds ^ " data");
   276 
   277 fun err_method name kind =
   278   error ("Error while invoking " ^ quote kind ^ " " ^ name ^ " method");
   279 
   280 fun err_dup_init sg kind =
   281   error ("Duplicate initialization of " ^ quote kind ^ " data" ^ of_theory sg);
   282 
   283 fun err_uninit sg kind =
   284   error ("Tried to access uninitialized " ^ quote kind ^ " data" ^ of_theory sg);
   285 
   286 fun err_access sg kind =
   287   error ("Unauthorized access to " ^ quote kind ^ " data" ^ of_theory sg);
   288 
   289 
   290 (* prepare data *)
   291 
   292 val empty_data = Data Symtab.empty;
   293 
   294 fun merge_data (Data tab1, Data tab2) =
   295   let
   296     val data1 = map snd (Symtab.dest tab1);
   297     val data2 = map snd (Symtab.dest tab2);
   298     val all_data = data1 @ data2;
   299     val kinds = gen_distinct Object.eq_kind (map fst all_data);
   300 
   301    fun entry data kind =
   302      (case gen_assoc Object.eq_kind (data, kind) of
   303        None => []
   304      | Some x => [(kind, x)]);
   305 
   306     fun merge_entries [(kind, (e, mths as (ext, _, _)))] =
   307           (kind, (ext e handle _ => err_method "prep_ext" (Object.name_of_kind kind), mths))
   308       | merge_entries [(kind, (e1, mths as (_, mrg, _))), (_, (e2, _))] =
   309           (kind, (mrg (e1, e2) handle _ => err_method "merge" (Object.name_of_kind kind), mths))
   310       | merge_entries _ = sys_error "merge_entries";
   311 
   312     val data = map (fn k => merge_entries (entry data1 k @ entry data2 k)) kinds;
   313     val data_idx = map (fn (k, x) => (Object.name_of_kind k, (k, x))) data;
   314   in
   315     Data (Symtab.make data_idx)
   316       handle Symtab.DUPS dups => err_inconsistent dups
   317   end;
   318 
   319 fun prep_ext_data data = merge_data (data, empty_data);
   320 
   321 fun init_data_sg sg (Data tab) kind e ext mrg prt =
   322   let val name = Object.name_of_kind kind in
   323     Data (Symtab.update_new ((name, (kind, (e, (ext, mrg, prt)))), tab))
   324       handle Symtab.DUP _ => err_dup_init sg name
   325   end;
   326 
   327 
   328 (* access data *)
   329 
   330 fun data_kinds (Data tab) = map fst (Symtab.dest tab);
   331 
   332 fun lookup_data sg tab kind =
   333   let val name = Object.name_of_kind kind in
   334     (case Symtab.lookup (tab, name) of
   335       Some (k, x) =>
   336         if Object.eq_kind (kind, k) then x
   337         else err_access sg name
   338     | None => err_uninit sg name)
   339   end;
   340 
   341 fun get_data kind f (sg as Sg (_, {data = Data tab, ...})) =
   342   let val x = fst (lookup_data sg tab kind)
   343   in f x handle Match => Object.kind_error kind end;
   344 
   345 fun print_data kind (sg as Sg (_, {data = Data tab, ...})) =
   346   let val (e, (_, _, prt)) = lookup_data sg tab kind
   347   in prt sg e handle _ => err_method ("print" ^ of_theory sg) (Object.name_of_kind kind) end;
   348 
   349 fun put_data_sg sg (Data tab) kind f x =
   350   Data (Symtab.update ((Object.name_of_kind kind,
   351     (kind, (f x, snd (lookup_data sg tab kind)))), tab));
   352 
   353 
   354 
   355 (** build signatures **)
   356 
   357 fun ext_stamps stamps (id as ref name) =
   358   let val stmps = (case stamps of ref "#" :: ss => ss | ss => ss) in
   359     if exists (equal name o !) stmps then
   360       error ("Theory already contains a " ^ quote name ^ " component")
   361     else id :: stmps
   362   end;
   363 
   364 fun create_sign self stamps name (syn, tsig, ctab, (path, spaces), data) =
   365   let
   366     val id = ref name;
   367     val sign =
   368       make_sign (id, self, tsig, ctab, syn, path, spaces, data, ext_stamps stamps id);
   369   in
   370     (case self of
   371       SgRef (Some r) => r := sign
   372     | _ => sys_error "Sign.create_sign");
   373     sign
   374   end;
   375 
   376 fun extend_sign keep extfun name decls
   377     (sg as Sg ({id = _, stamps}, {self, tsig, const_tab, syn, path, spaces, data})) =
   378   let
   379     val _ = check_stale sg;
   380     val (self', data') =
   381       if is_draft sg andalso keep then (self, data)
   382       else (SgRef (Some (ref sg)), prep_ext_data data);
   383   in
   384     create_sign self' stamps name
   385       (extfun (syn, tsig, const_tab, (path, spaces), data') decls)
   386   end;
   387 
   388 
   389 
   390 (** name spaces **)
   391 
   392 (* kinds *)
   393 
   394 val classK = "class";
   395 val typeK = "type";
   396 val constK = "const";
   397 
   398 
   399 (* add and retrieve names *)
   400 
   401 fun space_of spaces kind =
   402   if_none (assoc (spaces, kind)) NameSpace.empty;
   403 
   404 (*input and output of qualified names*)
   405 fun intrn spaces kind = NameSpace.intern (space_of spaces kind);
   406 fun extrn spaces kind = NameSpace.extern (space_of spaces kind);
   407 fun cond_extrn spaces kind = NameSpace.cond_extern (space_of spaces kind);
   408 
   409 (*add names*)
   410 fun add_names spaces kind names =
   411   let val space' = NameSpace.extend (space_of spaces kind, names) in
   412     overwrite (spaces, (kind, space'))
   413   end;
   414 
   415 (*make full names*)
   416 fun full path name =
   417   if name = "" then error "Attempt to declare empty name \"\""
   418   else if NameSpace.qualified name then
   419     error ("Attempt to declare qualified name " ^ quote name)
   420   else NameSpace.pack (path @ [name]);
   421 
   422 (*base name*)
   423 val base_name = NameSpace.base;
   424 
   425 
   426 (* intern / extern names *)
   427 
   428 local
   429   (*prepare mapping of names*)
   430   fun mapping f add_xs t =
   431     let
   432       fun f' x = let val y = f x in if x = y then None else Some (x, y) end;
   433       val table = mapfilter f' (add_xs (t, []));
   434       fun lookup x = if_none (assoc (table, x)) x;
   435     in lookup end;
   436 
   437   (*intern / extern typ*)
   438   fun trn_typ trn T =
   439     T |> map_typ
   440       (mapping (trn classK) add_typ_classes T)
   441       (mapping (trn typeK) add_typ_tycons T);
   442 
   443   (*intern / extern term*)
   444   fun trn_term trn t =
   445     t |> map_term
   446       (mapping (trn classK) add_term_classes t)
   447       (mapping (trn typeK) add_term_tycons t)
   448       (mapping (trn constK) add_term_consts t);
   449 
   450   val spaces_of = #spaces o rep_sg;
   451 in
   452   fun intrn_class spaces = intrn spaces classK;
   453   fun extrn_class spaces = extrn spaces classK;
   454 
   455   val intrn_sort = map o intrn_class;
   456   val intrn_typ = trn_typ o intrn;
   457   val intrn_term = trn_term o intrn;
   458 
   459   val extrn_sort = map o extrn_class;
   460   val extrn_typ = trn_typ o extrn;
   461   val extrn_term = trn_term o extrn;
   462 
   463   fun intrn_tycons spaces T =
   464     map_typ I (mapping (intrn spaces typeK) add_typ_tycons T) T;
   465 
   466   val intern = intrn o spaces_of;
   467   val extern = extrn o spaces_of;
   468   val cond_extern = cond_extrn o spaces_of;
   469 
   470   val intern_class = intrn_class o spaces_of;
   471   val intern_sort = intrn_sort o spaces_of;
   472   val intern_typ = intrn_typ o spaces_of;
   473   val intern_term = intrn_term o spaces_of;
   474 
   475   fun intern_tycon sg = intrn (spaces_of sg) typeK;
   476   fun intern_const sg = intrn (spaces_of sg) constK;
   477 
   478   val intern_tycons = intrn_tycons o spaces_of;
   479 
   480   val full_name = full o #path o rep_sg;
   481   fun full_name_path sg elems name =
   482     full (#path (rep_sg sg) @ NameSpace.unpack elems) name;
   483 end;
   484 
   485 
   486 
   487 (** pretty printing of terms, types etc. **)
   488 
   489 fun pretty_term (sg as Sg ({stamps, ...}, {syn, spaces, ...})) t =
   490   Syntax.pretty_term syn
   491     (exists (equal "CPure" o !) stamps)
   492     (if ! NameSpace.long_names then t else extrn_term spaces t);
   493 
   494 fun pretty_typ (Sg (_, {syn, spaces, ...})) T =
   495   Syntax.pretty_typ syn
   496     (if ! NameSpace.long_names then T else extrn_typ spaces T);
   497 
   498 fun pretty_sort (Sg (_, {syn, spaces, ...})) S =
   499   Syntax.pretty_sort syn
   500     (if ! NameSpace.long_names then S else extrn_sort spaces S);
   501 
   502 fun pretty_classrel sg (c1, c2) = Pretty.block
   503   [pretty_sort sg [c1], Pretty.str " <", Pretty.brk 1, pretty_sort sg [c2]];
   504 
   505 fun pretty_arity sg (t, Ss, S) =
   506   let
   507     val t' = cond_extern sg typeK t;
   508     val dom =
   509       if null Ss then []
   510       else [Pretty.list "(" ")" (map (pretty_sort sg) Ss), Pretty.brk 1];
   511   in
   512     Pretty.block
   513       ([Pretty.str (t' ^ " ::"), Pretty.brk 1] @ dom @ [pretty_sort sg S])
   514   end;
   515 
   516 fun string_of_term sg t = Pretty.string_of (pretty_term sg t);
   517 fun string_of_typ sg T = Pretty.string_of (pretty_typ sg T);
   518 fun string_of_sort sg S = Pretty.string_of (pretty_sort sg S);
   519 
   520 fun str_of_sort sg S = Pretty.str_of (pretty_sort sg S);
   521 fun str_of_classrel sg c1_c2 = Pretty.str_of (pretty_classrel sg c1_c2);
   522 fun str_of_arity sg ar = Pretty.str_of (pretty_arity sg ar);
   523 
   524 fun pprint_term sg = Pretty.pprint o Pretty.quote o (pretty_term sg);
   525 fun pprint_typ sg = Pretty.pprint o Pretty.quote o (pretty_typ sg);
   526 
   527 
   528 
   529 (** read types **)  (*exception ERROR*)
   530 
   531 fun err_in_type s =
   532   error ("The error(s) above occurred in type " ^ quote s);
   533 
   534 fun rd_raw_typ syn tsig spaces def_sort str =
   535   intrn_tycons spaces
   536     (Syntax.read_typ syn (Type.get_sort tsig def_sort (intrn_sort spaces)) str
   537       handle ERROR => err_in_type str);
   538 
   539 fun read_raw_typ (sg as Sg (_, {tsig, syn, spaces, ...}), def_sort) str =
   540   (check_stale sg; rd_raw_typ syn tsig spaces def_sort str);
   541 
   542 (*read and certify typ wrt a signature*)
   543 fun read_typ (sg, def_sort) str =
   544   (Type.cert_typ (tsig_of sg) (read_raw_typ (sg, def_sort) str)
   545       handle TYPE (msg, _, _) => (error_msg msg; err_in_type str));
   546 
   547 
   548 
   549 (** certify types and terms **)   (*exception TYPE*)
   550 
   551 (* certify_typ *)
   552 
   553 val certify_typ = Type.cert_typ o tsig_of;
   554 
   555 
   556 (* certify_term *)
   557 
   558 (*check for duplicate TVars with distinct sorts*)
   559 fun nodup_TVars (tvars, T) =
   560   (case T of
   561     Type (_, Ts) => nodup_TVars_list (tvars, Ts)
   562   | TFree _ => tvars
   563   | TVar (v as (a, S)) =>
   564       (case assoc_string_int (tvars, a) of
   565         Some S' =>
   566           if S = S' then tvars
   567           else raise TYPE ("Type variable " ^ Syntax.string_of_vname a ^
   568             " has two distinct sorts", [TVar (a, S'), T], [])
   569       | None => v :: tvars))
   570 (*equivalent to foldl nodup_TVars_list, but 3X faster under Poly/ML*)
   571 and nodup_TVars_list (tvars, []) = tvars
   572   | nodup_TVars_list (tvars, T :: Ts) =
   573       nodup_TVars_list (nodup_TVars (tvars, T), Ts);
   574 
   575 (*check for duplicate Vars with distinct types*)
   576 fun nodup_Vars tm =
   577   let
   578     fun nodups vars tvars tm =
   579       (case tm of
   580         Const (c, T) => (vars, nodup_TVars (tvars, T))
   581       | Free (a, T) => (vars, nodup_TVars (tvars, T))
   582       | Var (v as (ixn, T)) =>
   583           (case assoc_string_int (vars, ixn) of
   584             Some T' =>
   585               if T = T' then (vars, nodup_TVars (tvars, T))
   586               else raise TYPE ("Variable " ^ Syntax.string_of_vname ixn ^
   587                 " has two distinct types", [T', T], [])
   588           | None => (v :: vars, tvars))
   589       | Bound _ => (vars, tvars)
   590       | Abs (_, T, t) => nodups vars (nodup_TVars (tvars, T)) t
   591       | s $ t =>
   592           let val (vars',tvars') = nodups vars tvars s in
   593             nodups vars' tvars' t
   594           end);
   595   in nodups [] [] tm; () end;
   596 
   597 (*compute and check type of the term*)
   598 fun type_check sg tm =
   599   let
   600     val prt =
   601       setmp Syntax.show_brackets true
   602         (setmp NameSpace.long_names true (pretty_term sg));
   603     val prT = setmp NameSpace.long_names true (pretty_typ sg);
   604 
   605     fun err_appl why bs t T u U =
   606       let
   607         val xs = map Free bs;		(*we do not rename here*)
   608         val t' = subst_bounds (xs, t);
   609         val u' = subst_bounds (xs, u);
   610         val text = cat_lines(TypeInfer.appl_error prt prT why t' T u' U);
   611       in raise TYPE (text, [T, U], [t', u']) end;
   612 
   613     fun typ_of (_, Const (_, T)) = T
   614       | typ_of (_, Free  (_, T)) = T
   615       | typ_of (_, Var (_, T)) = T
   616       | typ_of (bs, Bound i) = snd (nth_elem (i, bs) handle LIST _ =>
   617           raise TYPE ("Loose bound variable: B." ^ string_of_int i, [], [Bound i]))
   618       | typ_of (bs, Abs (x, T, body)) = T --> typ_of ((x, T) :: bs, body)
   619       | typ_of (bs, t $ u) =
   620           let val T = typ_of (bs, t) and U = typ_of (bs, u) in
   621             (case T of
   622               Type ("fun", [T1, T2]) =>
   623                 if T1 = U then T2 else err_appl "Incompatible operand type." bs t T u U
   624             | _ => err_appl "Operator not of function type." bs t T u U)
   625           end;
   626 
   627   in typ_of ([], tm) end;
   628 
   629 
   630 fun certify_term sg tm =
   631   let
   632     val _ = check_stale sg;
   633     val tsig = tsig_of sg;
   634 
   635     fun show_const a T = quote a ^ " :: " ^ quote (string_of_typ sg T);
   636 
   637     fun atom_err (errs, Const (a, T)) =
   638         (case const_type sg a of
   639           None => ("Undeclared constant " ^ show_const a T) :: errs
   640         | Some U =>
   641             if Type.typ_instance (tsig, T, U) then errs
   642             else ("Illegal type for constant " ^ show_const a T) :: errs)
   643       | atom_err (errs, Var ((x, i), _)) =
   644           if i < 0 then ("Negative index for Var " ^ quote x) :: errs else errs
   645       | atom_err (errs, _) = errs;
   646 
   647     val norm_tm =
   648       (case it_term_types (Type.typ_errors tsig) (tm, []) of
   649         [] => map_term_types (Type.norm_typ tsig) tm
   650       | errs => raise TYPE (cat_lines errs, [], [tm]));
   651     val _ = nodup_Vars norm_tm;
   652   in
   653     (case foldl_aterms atom_err ([], norm_tm) of
   654       [] => (norm_tm, type_check sg norm_tm, maxidx_of_term norm_tm)
   655     | errs => raise TYPE (cat_lines errs, [], [norm_tm]))
   656   end;
   657 
   658 
   659 
   660 (** infer_types **)         (*exception ERROR*)
   661 
   662 (*
   663   def_type: partial map from indexnames to types (constrains Frees, Vars)
   664   def_sort: partial map from indexnames to sorts (constrains TFrees, TVars)
   665   used: list of already used type variables
   666   freeze: if true then generated parameters are turned into TFrees, else TVars
   667 
   668   termss: lists of alternative parses (only one combination should be type-correct)
   669   typs: expected types
   670 *)
   671 
   672 fun infer_types_simult sg def_type def_sort used freeze args =
   673   let
   674     val tsig = tsig_of sg;
   675     val prt =
   676       setmp Syntax.show_brackets true
   677         (setmp NameSpace.long_names true (pretty_term sg));
   678     val prT = setmp NameSpace.long_names true (pretty_typ sg);
   679 
   680     val termss = foldr multiply (map fst args, [[]]);
   681     val typs =
   682       map (fn (_, T) => certify_typ sg T handle TYPE (msg, _, _) => error msg) args;
   683 
   684     fun infer ts = OK
   685       (Type.infer_types prt prT tsig (const_type sg) def_type def_sort
   686         (intern_const sg) (intern_tycons sg) (intern_sort sg) used freeze typs ts)
   687       handle TYPE (msg, _, _) => Error msg;
   688 
   689     val err_results = map infer termss;
   690     val errs = mapfilter get_error err_results;
   691     val results = mapfilter get_ok err_results;
   692 
   693     val ambiguity = length termss;	(* FIXME !? *)
   694     (* FIXME to syntax.ML!? *)
   695     fun ambig_msg () =
   696       if ambiguity > 1 andalso ambiguity <= ! Syntax.ambiguity_level
   697       then
   698         error_msg "Got more than one parse tree.\n\
   699           \Retry with smaller Syntax.ambiguity_level for more information."
   700       else ();
   701   in
   702     if null results then (ambig_msg (); error (cat_lines errs))
   703     else if length results = 1 then
   704       (if ambiguity > ! Syntax.ambiguity_level then
   705         warning "Fortunately, only one parse tree is type correct.\n\
   706           \You may still want to disambiguate your grammar or your input."
   707       else (); hd results)
   708     else (ambig_msg (); error ("More than one term is type correct:\n" ^
   709       (cat_lines (map (Pretty.string_of o prt) (flat (map fst results))))))
   710   end;
   711 
   712 
   713 fun infer_types sg def_type def_sort used freeze tsT =
   714   apfst hd (infer_types_simult sg def_type def_sort used freeze [tsT]);
   715 
   716 
   717 
   718 (** extend signature **)    (*exception ERROR*)
   719 
   720 (** signature extension functions **)  (*exception ERROR*)
   721 
   722 fun decls_of path name_of mfixs =
   723   map (fn (x, y, mx) => (full path (name_of x mx), y)) mfixs;
   724 
   725 fun no_read _ _ _ decl = decl;
   726 
   727 
   728 (* add default sort *)
   729 
   730 fun ext_defsort int (syn, tsig, ctab, (path, spaces), data) S =
   731   (syn, Type.ext_tsig_defsort tsig (if int then intrn_sort spaces S else S),
   732     ctab, (path, spaces), data);
   733 
   734 
   735 (* add type constructors *)
   736 
   737 fun ext_types (syn, tsig, ctab, (path, spaces), data) types =
   738   let val decls = decls_of path Syntax.type_name types in
   739     (Syntax.extend_type_gram syn types,
   740       Type.ext_tsig_types tsig decls, ctab,
   741       (path, add_names spaces typeK (map fst decls)), data)
   742   end;
   743 
   744 fun ext_nonterminals sg nonterms =
   745   ext_types sg (map (fn n => (n, 0, Syntax.NoSyn)) nonterms);
   746 
   747 
   748 (* add type abbreviations *)
   749 
   750 fun read_abbr syn tsig spaces (t, vs, rhs_src) =
   751   (t, vs, rd_raw_typ syn tsig spaces (K None) rhs_src)
   752     handle ERROR => error ("in type abbreviation " ^ t);
   753 
   754 fun ext_abbrs rd_abbr (syn, tsig, ctab, (path, spaces), data) abbrs =
   755   let
   756     fun mfix_of (t, vs, _, mx) = (t, length vs, mx);
   757     val syn' = Syntax.extend_type_gram syn (map mfix_of abbrs);
   758 
   759     val abbrs' =
   760       map (fn (t, vs, rhs, mx) =>
   761         (full path (Syntax.type_name t mx), vs, rhs)) abbrs;
   762     val spaces' = add_names spaces typeK (map #1 abbrs');
   763     val decls = map (rd_abbr syn' tsig spaces') abbrs';
   764   in
   765     (syn', Type.ext_tsig_abbrs tsig decls, ctab, (path, spaces'), data)
   766   end;
   767 
   768 fun ext_tyabbrs abbrs = ext_abbrs read_abbr abbrs;
   769 fun ext_tyabbrs_i abbrs = ext_abbrs no_read abbrs;
   770 
   771 
   772 (* add type arities *)
   773 
   774 fun ext_arities int (syn, tsig, ctab, (path, spaces), data) arities =
   775   let
   776     fun intrn_arity (c, Ss, S) =
   777       (intrn spaces typeK c, map (intrn_sort spaces) Ss, intrn_sort spaces S);
   778     val intrn = if int then map intrn_arity else I;
   779     val tsig' = Type.ext_tsig_arities tsig (intrn arities);
   780     val log_types = Type.logical_types tsig';
   781   in
   782     (Syntax.extend_log_types syn log_types, tsig', ctab, (path, spaces), data)
   783   end;
   784 
   785 
   786 (* add term constants and syntax *)
   787 
   788 fun const_name path c mx =
   789   full path (Syntax.const_name c mx);
   790 
   791 fun err_in_const c =
   792   error ("in declaration of constant " ^ quote c);
   793 
   794 fun err_dup_consts cs =
   795   error ("Duplicate declaration of constant(s) " ^ commas_quote cs);
   796 
   797 
   798 fun read_const syn tsig (path, spaces) (c, ty_src, mx) =
   799   (c, rd_raw_typ syn tsig spaces (K None) ty_src, mx)
   800     handle ERROR => err_in_const (const_name path c mx);
   801 
   802 fun ext_cnsts rd_const syn_only prmode (syn, tsig, ctab, (path, spaces), data) raw_consts =
   803   let
   804     fun prep_const (c, ty, mx) =
   805       (c, compress_type (Type.varifyT (Type.cert_typ tsig (Type.no_tvars ty))), mx)
   806         handle TYPE (msg, _, _) =>
   807           (error_msg msg; err_in_const (const_name path c mx));
   808 
   809     val consts = map (prep_const o rd_const syn tsig (path, spaces)) raw_consts;
   810     val decls =
   811       if syn_only then []
   812       else decls_of path Syntax.const_name consts;
   813   in
   814     (Syntax.extend_const_gram syn prmode consts, tsig,
   815       Symtab.extend (ctab, decls)
   816         handle Symtab.DUPS cs => err_dup_consts cs,
   817       (path, add_names spaces constK (map fst decls)), data)
   818   end;
   819 
   820 fun ext_consts_i sg = ext_cnsts no_read false ("", true) sg;
   821 fun ext_consts sg = ext_cnsts read_const false ("", true) sg;
   822 fun ext_syntax_i sg = ext_cnsts no_read true ("", true) sg;
   823 fun ext_syntax sg = ext_cnsts read_const true ("", true) sg;
   824 fun ext_modesyntax_i sg (prmode, consts) = ext_cnsts no_read true prmode sg consts;
   825 fun ext_modesyntax sg (prmode, consts) = ext_cnsts read_const true prmode sg consts;
   826 
   827 
   828 (* add type classes *)
   829 
   830 fun const_of_class c = c ^ "_class";
   831 
   832 fun class_of_const c_class =
   833   let
   834     val c = implode (take (size c_class - size "_class", explode c_class));
   835   in
   836     if const_of_class c = c_class then c
   837     else raise TERM ("class_of_const: bad name " ^ quote c_class, [])
   838   end;
   839 
   840 
   841 fun ext_classes int (syn, tsig, ctab, (path, spaces), data) classes =
   842   let
   843     val names = map fst classes;
   844     val consts =
   845       map (fn c => (const_of_class c, a_itselfT --> propT, NoSyn)) names;
   846 
   847     val full_names = map (full path) names;
   848     val spaces' = add_names spaces classK full_names;
   849     val intrn = if int then map (intrn_class spaces') else I;
   850     val classes' =
   851       ListPair.map (fn (c, (_, cs)) => (c, intrn cs)) (full_names, classes);
   852   in
   853     ext_consts_i
   854       (Syntax.extend_consts syn names,
   855         Type.ext_tsig_classes tsig classes', ctab, (path, spaces'), data)
   856     consts
   857   end;
   858 
   859 
   860 (* add to classrel *)
   861 
   862 fun ext_classrel int (syn, tsig, ctab, (path, spaces), data) pairs =
   863   let val intrn = if int then map (pairself (intrn_class spaces)) else I in
   864     (syn, Type.ext_tsig_classrel tsig (intrn pairs), ctab, (path, spaces), data)
   865   end;
   866 
   867 
   868 (* add translation rules *)
   869 
   870 fun ext_trrules (syn, tsig, ctab, (path, spaces), data) args =
   871   (Syntax.extend_trrules syn
   872     (map (Syntax.map_trrule (fn (root, str) => (intrn spaces typeK root, str))) args),
   873       tsig, ctab, (path, spaces), data);
   874 
   875 
   876 (* add to syntax *)
   877 
   878 fun ext_syn extfun (syn, tsig, ctab, names, data) args =
   879   (extfun syn args, tsig, ctab, names, data);
   880 
   881 
   882 (* add to path *)
   883 
   884 fun ext_path (syn, tsig, ctab, (path, spaces), data) elems =
   885   let
   886     val path' =
   887       if elems = ".." andalso not (null path) then fst (split_last path)
   888       else if elems = "/" then []
   889       else path @ NameSpace.unpack elems;
   890   in
   891     (syn, tsig, ctab, (path', spaces), data)
   892   end;      
   893 
   894 
   895 (* add to name space *)
   896 
   897 fun ext_space (syn, tsig, ctab, (path, spaces), data) (kind, names) =
   898   (syn, tsig, ctab, (path, add_names spaces kind names), data);
   899 
   900 
   901 (* signature data *)
   902 
   903 fun ext_init_data sg (syn, tsig, ctab, names, data) (kind, (e, ext, mrg, prt)) =
   904   (syn, tsig, ctab, names, init_data_sg sg data kind e ext mrg prt);
   905 
   906 fun ext_put_data sg (syn, tsig, ctab, names, data) (kind, f, x) =
   907   (syn, tsig, ctab, names, put_data_sg sg data kind f x);
   908 
   909 
   910 (* the external interfaces *)
   911 
   912 val add_classes       = extend_sign true (ext_classes true) "#";
   913 val add_classes_i     = extend_sign true (ext_classes false) "#";
   914 val add_classrel      = extend_sign true (ext_classrel true) "#";
   915 val add_classrel_i    = extend_sign true (ext_classrel false) "#";
   916 val add_defsort       = extend_sign true (ext_defsort true) "#";
   917 val add_defsort_i     = extend_sign true (ext_defsort false) "#";
   918 val add_types         = extend_sign true ext_types "#";
   919 val add_nonterminals  = extend_sign true ext_nonterminals "#";
   920 val add_tyabbrs       = extend_sign true ext_tyabbrs "#";
   921 val add_tyabbrs_i     = extend_sign true ext_tyabbrs_i "#";
   922 val add_arities       = extend_sign true (ext_arities true) "#";
   923 val add_arities_i     = extend_sign true (ext_arities false) "#";
   924 val add_consts        = extend_sign true ext_consts "#";
   925 val add_consts_i      = extend_sign true ext_consts_i "#";
   926 val add_syntax        = extend_sign true ext_syntax "#";
   927 val add_syntax_i      = extend_sign true ext_syntax_i "#";
   928 val add_modesyntax    = extend_sign true ext_modesyntax "#";
   929 val add_modesyntax_i  = extend_sign true ext_modesyntax_i "#";
   930 val add_trfuns        = extend_sign true (ext_syn Syntax.extend_trfuns) "#";
   931 val add_trfunsT       = extend_sign true (ext_syn Syntax.extend_trfunsT) "#";
   932 val add_tokentrfuns   = extend_sign true (ext_syn Syntax.extend_tokentrfuns) "#";
   933 val add_trrules       = extend_sign true ext_trrules "#";
   934 val add_trrules_i     = extend_sign true (ext_syn Syntax.extend_trrules_i) "#";
   935 val add_path          = extend_sign true ext_path "#";
   936 val add_space         = extend_sign true ext_space "#";
   937 fun init_data arg sg  = extend_sign true (ext_init_data sg) "#" arg sg;
   938 fun put_data k f x sg = extend_sign true (ext_put_data sg) "#" (k, f, x) sg;
   939 fun add_name name sg  = extend_sign true K name () sg;
   940 fun prep_ext sg       = extend_sign false K "#" () sg;
   941 
   942 
   943 
   944 (** merge signatures **)    	(*exception TERM*)
   945 
   946 (* merge_stamps *)
   947 
   948 fun merge_stamps stamps1 stamps2 =
   949   let val stamps = merge_rev_lists stamps1 stamps2 in
   950     (case duplicates (map ! stamps) of
   951       [] => stamps
   952     | dups => raise TERM ("Attempt to merge different versions of theories "
   953         ^ commas_quote dups, []))
   954   end;
   955 
   956 
   957 (* implicit merge -- trivial only *)
   958 
   959 fun merge_refs (sgr1 as SgRef (Some (ref (sg1 as Sg ({stamps = s1, ...}, _)))),
   960         sgr2 as SgRef (Some (ref (sg2 as Sg ({stamps = s2, ...}, _))))) =
   961       if fast_subsig (sg2, sg1) then sgr1
   962       else if fast_subsig (sg1, sg2) then sgr2
   963       else if subsig (sg2, sg1) then sgr1
   964       else if subsig (sg1, sg2) then sgr2
   965       else (merge_stamps s1 s2; (*check for different versions*)
   966         raise TERM ("Attempt to do non-trivial merge of signatures", []))
   967   | merge_refs _ = sys_error "Sign.merge_refs";
   968 
   969 val merge = deref o merge_refs o pairself self_ref;
   970 
   971 
   972 (* proper merge *)
   973 
   974 fun merge_aux (sg1, sg2) =
   975   if subsig (sg2, sg1) then sg1
   976   else if subsig (sg1, sg2) then sg2
   977   else if is_draft sg1 orelse is_draft sg2 then
   978     raise TERM ("Attempt to merge draft signatures", [])
   979   else
   980     (*neither is union already; must form union*)
   981     let
   982       val Sg ({id = _, stamps = stamps1}, {self = _, tsig = tsig1, const_tab = const_tab1,
   983         syn = syn1, path = _, spaces = spaces1, data = data1}) = sg1;
   984       val Sg ({id = _, stamps = stamps2}, {self = _, tsig = tsig2, const_tab = const_tab2,
   985         syn = syn2, path = _, spaces = spaces2, data = data2}) = sg2;
   986 
   987       val id = ref "";
   988       val self_ref = ref sg1;                   (*dummy value*)
   989       val self = SgRef (Some self_ref);
   990 
   991       val stamps = merge_stamps stamps1 stamps2;
   992       val tsig = Type.merge_tsigs (tsig1, tsig2);
   993       val const_tab = Symtab.merge (op =) (const_tab1, const_tab2)
   994         handle Symtab.DUPS cs =>
   995           raise TERM ("Incompatible types for constant(s) " ^ commas_quote cs, []);
   996       val syn = Syntax.merge_syntaxes syn1 syn2;
   997 
   998       val path = [];
   999       val kinds = distinct (map fst (spaces1 @ spaces2));
  1000       val spaces =
  1001         kinds ~~
  1002           ListPair.map NameSpace.merge
  1003             (map (space_of spaces1) kinds, map (space_of spaces2) kinds);
  1004 
  1005       val data = merge_data (data1, data2);
  1006 
  1007       val sign = make_sign (id, self, tsig, const_tab, syn, path, spaces, data, stamps);
  1008     in
  1009       self_ref := sign; sign
  1010     end;
  1011 
  1012 fun nontriv_merge sg1_sg2 =
  1013   (case handle_error merge_aux sg1_sg2 of
  1014     OK sg => sg
  1015   | Error msg => raise TERM (msg, []));
  1016 
  1017 
  1018 
  1019 (** partial Pure signature **)
  1020 
  1021 val dummy_sg = make_sign (ref "", SgRef None, Type.tsig0,
  1022   Symtab.empty, Syntax.pure_syn, [], [], empty_data, []);
  1023 
  1024 val pre_pure =
  1025   create_sign (SgRef (Some (ref dummy_sg))) [] "#"
  1026     (Syntax.pure_syn, Type.tsig0, Symtab.empty, ([], []), empty_data);
  1027 
  1028 
  1029 end;