src/Pure/sign.ML
author clasohm
Fri Sep 01 13:27:48 1995 +0200 (1995-09-01)
changeset 1241 bfc93c86f0a1
parent 1239 2c0d94151e74
child 1393 73b6b003c6ca
permissions -rw-r--r--
added same_sg and same_thm
     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 signature SIGN =
     9 sig
    10   structure Symtab: SYMTAB
    11   structure Syntax: SYNTAX
    12   structure Type: TYPE
    13   sharing Symtab = Type.Symtab
    14   local open Type Syntax in
    15     type sg
    16     val rep_sg: sg ->
    17       {tsig: type_sig,
    18        const_tab: typ Symtab.table,
    19        syn: syntax,
    20        stamps: string ref list}
    21     val subsig: sg * sg -> bool
    22     val eq_sg: sg * sg -> bool
    23     val same_sg: sg * sg -> bool
    24     val is_draft: sg -> bool
    25     val const_type: sg -> string -> typ option
    26     val classes: sg -> class list
    27     val subsort: sg -> sort * sort -> bool
    28     val norm_sort: sg -> sort -> sort
    29     val nonempty_sort: sg -> sort list -> sort -> bool
    30     val print_sg: sg -> unit
    31     val pretty_sg: sg -> Pretty.T
    32     val pprint_sg: sg -> pprint_args -> unit
    33     val pretty_term: sg -> term -> Pretty.T
    34     val pretty_typ: sg -> typ -> Pretty.T
    35     val pretty_sort: sort -> Pretty.T
    36     val string_of_term: sg -> term -> string
    37     val string_of_typ: sg -> typ -> string
    38     val pprint_term: sg -> term -> pprint_args -> unit
    39     val pprint_typ: sg -> typ -> pprint_args -> unit
    40     val certify_typ: sg -> typ -> typ
    41     val certify_term: sg -> term -> term * typ * int
    42     val read_typ: sg * (indexname -> sort option) -> string -> typ
    43     val infer_types: sg -> (indexname -> typ option) ->
    44       (indexname -> sort option) -> string list -> bool
    45       -> term list * typ -> int * term * (indexname * typ) list
    46     val add_classes: (class * class list) list -> sg -> sg
    47     val add_classrel: (class * class) list -> sg -> sg
    48     val add_defsort: sort -> sg -> sg
    49     val add_types: (string * int * mixfix) list -> sg -> sg
    50     val add_tyabbrs: (string * string list * string * mixfix) list -> sg -> sg
    51     val add_tyabbrs_i: (string * string list * typ * mixfix) list -> sg -> sg
    52     val add_arities: (string * sort list * sort) list -> sg -> sg
    53     val add_consts: (string * string * mixfix) list -> sg -> sg
    54     val add_consts_i: (string * typ * mixfix) list -> sg -> sg
    55     val add_syntax: (string * string * mixfix) list -> sg -> sg
    56     val add_syntax_i: (string * typ * mixfix) list -> sg -> sg
    57     val add_trfuns:
    58       (string * (ast list -> ast)) list *
    59       (string * (term list -> term)) list *
    60       (string * (term list -> term)) list *
    61       (string * (ast list -> ast)) list -> sg -> sg
    62     val add_trrules: (string * string) trrule list -> sg -> sg
    63     val add_trrules_i: ast trrule list -> sg -> sg
    64     val add_name: string -> sg -> sg
    65     val make_draft: sg -> sg
    66     val merge: sg * sg -> sg
    67     val proto_pure: sg
    68     val pure: sg
    69     val cpure: sg
    70     val const_of_class: class -> string
    71     val class_of_const: string -> class
    72   end
    73 end;
    74 
    75 functor SignFun(structure Syntax: SYNTAX and Type: TYPE): SIGN =
    76 struct
    77 
    78 structure Symtab = Type.Symtab;
    79 structure Syntax = Syntax;
    80 structure BasicSyntax: BASIC_SYNTAX = Syntax;
    81 structure Pretty = Syntax.Pretty;
    82 structure Type = Type;
    83 open BasicSyntax Type;
    84 
    85 
    86 (** datatype sg **)
    87 
    88 (*the "ref" in stamps ensures that no two signatures are identical -- it is
    89   impossible to forge a signature*)
    90 
    91 datatype sg =
    92   Sg of {
    93     tsig: type_sig,                 (*order-sorted signature of types*)
    94     const_tab: typ Symtab.table,    (*types of constants*)
    95     syn: Syntax.syntax,             (*syntax for parsing and printing*)
    96     stamps: string ref list};       (*unique theory indentifier*)
    97 
    98 fun rep_sg (Sg args) = args;
    99 val tsig_of = #tsig o rep_sg;
   100 
   101 
   102 (* stamps *)
   103 
   104 fun is_draft (Sg {stamps = ref "#" :: _, ...}) = true
   105   | is_draft _ = false;
   106 
   107 fun subsig (Sg {stamps = s1, ...}, Sg {stamps = s2, ...}) = s1 subset s2;
   108 
   109 fun eq_sg (Sg {stamps = s1, ...}, Sg {stamps = s2, ...}) = eq_set (s1, s2);
   110 
   111 (* test if same theory names are contained in signatures' stamps,
   112    i.e. if signatures belong to same theory but not necessarily to the same
   113    version of it*)
   114 fun same_sg (Sg {stamps = s1, ...}, Sg {stamps = s2, ...}) =
   115   eq_set (pairself (map (op !)) (s1, s2));
   116 
   117 
   118 (* consts *)
   119 
   120 fun const_type (Sg {const_tab, ...}) c =
   121   Symtab.lookup (const_tab, c);
   122 
   123 
   124 (* classes and sorts *)
   125 
   126 val classes = #classes o Type.rep_tsig o tsig_of;
   127 
   128 val subsort = Type.subsort o tsig_of;
   129 val norm_sort = Type.norm_sort o tsig_of;
   130 val nonempty_sort = Type.nonempty_sort o tsig_of;
   131 
   132 fun pretty_sort [c] = Pretty.str c
   133   | pretty_sort cs = Pretty.str_list "{" "}" cs;
   134 
   135 
   136 
   137 (** print signature **)
   138 
   139 val stamp_names = rev o map !;
   140 
   141 fun print_sg sg =
   142   let
   143     fun prt_typ syn ty = Pretty.quote (Syntax.pretty_typ syn ty);
   144 
   145     fun pretty_subclass (cl, cls) = Pretty.block
   146       (Pretty.str (cl ^ " <") :: Pretty.brk 1 ::
   147         Pretty.commas (map Pretty.str cls));
   148 
   149     fun pretty_default cls = Pretty.block
   150       [Pretty.str "default:", Pretty.brk 1, pretty_sort cls];
   151 
   152     fun pretty_ty (ty, n) = Pretty.str (ty ^ " " ^ string_of_int n);
   153 
   154     fun pretty_abbr syn (ty, (vs, rhs)) = Pretty.block
   155       [prt_typ syn (Type (ty, map (fn v => TVar ((v, 0), [])) vs)),
   156         Pretty.str " =", Pretty.brk 1, prt_typ syn rhs];
   157 
   158     fun pretty_arity ty (cl, []) = Pretty.block
   159           [Pretty.str (ty ^ " ::"), Pretty.brk 1, Pretty.str cl]
   160       | pretty_arity ty (cl, srts) = Pretty.block
   161           [Pretty.str (ty ^ " ::"), Pretty.brk 1,
   162             Pretty.list "(" ")" (map pretty_sort srts),
   163             Pretty.brk 1, Pretty.str cl];
   164 
   165     fun pretty_arities (ty, ars) = map (pretty_arity ty) ars;
   166 
   167     fun pretty_const syn (c, ty) = Pretty.block
   168       [Pretty.str (quote c ^ " ::"), Pretty.brk 1, prt_typ syn ty];
   169 
   170 
   171     val Sg {tsig, const_tab, syn, stamps} = sg;
   172     val {classes, subclass, default, tycons, abbrs, arities} = rep_tsig tsig;
   173   in
   174     Pretty.writeln (Pretty.strs ("stamps:" :: stamp_names stamps));
   175     Pretty.writeln (Pretty.strs ("classes:" :: classes));
   176     Pretty.writeln (Pretty.big_list "subclass:"
   177                       (map pretty_subclass subclass));
   178     Pretty.writeln (pretty_default default);
   179     Pretty.writeln (Pretty.big_list "types:" (map pretty_ty tycons));
   180     Pretty.writeln (Pretty.big_list "abbrs:" (map (pretty_abbr syn) abbrs));
   181     Pretty.writeln (Pretty.big_list "arities:"
   182                       (flat (map pretty_arities arities)));
   183     Pretty.writeln (Pretty.big_list "consts:"
   184                       (map (pretty_const syn) (Symtab.dest const_tab)))
   185   end;
   186 
   187 
   188 fun pretty_sg (Sg {stamps, ...}) =
   189   Pretty.str_list "{" "}" (stamp_names stamps);
   190 
   191 val pprint_sg = Pretty.pprint o pretty_sg;
   192 
   193 
   194 
   195 (** pretty printing of terms and types **)
   196 
   197 fun pretty_term (Sg {syn, stamps, ...}) =
   198   let val curried = "CPure" mem (map ! stamps);
   199   in Syntax.pretty_term curried syn end;
   200 
   201 fun pretty_typ (Sg {syn, ...}) = Syntax.pretty_typ syn;
   202 
   203 fun string_of_term (Sg {syn, stamps, ...}) =
   204   let val curried = "CPure" mem (map ! stamps);
   205   in Syntax.string_of_term curried syn end;
   206 
   207 fun string_of_typ (Sg {syn, ...}) = Syntax.string_of_typ syn;
   208 
   209 fun pprint_term sg = Pretty.pprint o Pretty.quote o (pretty_term sg);
   210 fun pprint_typ sg = Pretty.pprint o Pretty.quote o (pretty_typ sg);
   211 
   212 
   213 
   214 (** read types **)  (*exception ERROR*)
   215 
   216 fun err_in_type s =
   217   error ("The error(s) above occurred in type " ^ quote s);
   218 
   219 fun read_raw_typ syn tsig sort_of str =
   220   Syntax.read_typ syn (fn x => if_none (sort_of x) (defaultS tsig)) str
   221     handle ERROR => err_in_type str;
   222 
   223 (*read and certify typ wrt a signature*)
   224 fun read_typ (Sg {tsig, syn, ...}, sort_of) str =
   225   cert_typ tsig (read_raw_typ syn tsig sort_of str)
   226     handle TYPE (msg, _, _) => (writeln msg; err_in_type str);
   227 
   228 
   229 
   230 (** certify types and terms **)   (*exception TYPE*)
   231 
   232 fun certify_typ (Sg {tsig, ...}) ty = cert_typ tsig ty;
   233 
   234 
   235 fun mapfilt_atoms f (Abs (_, _, t)) = mapfilt_atoms f t
   236   | mapfilt_atoms f (t $ u) = mapfilt_atoms f t @ mapfilt_atoms f u
   237   | mapfilt_atoms f a = (case f a of Some y => [y] | None => []);
   238 
   239 fun certify_term (sg as Sg {tsig, ...}) tm =
   240   let
   241     fun valid_const a T =
   242       (case const_type sg a of
   243         Some U => typ_instance (tsig, T, U)
   244       | _ => false);
   245 
   246     fun atom_err (Const (a, T)) =
   247           if valid_const a T then None
   248           else Some ("Illegal type for constant " ^ quote a ^ " :: " ^
   249             quote (string_of_typ sg T))
   250       | atom_err (Var ((x, i), _)) =
   251           if i < 0 then Some ("Negative index for Var " ^ quote x) else None
   252       | atom_err _ = None;
   253 
   254     val norm_tm =
   255       (case it_term_types (typ_errors tsig) (tm, []) of
   256         [] => map_term_types (norm_typ tsig) tm
   257       | errs => raise_type (cat_lines errs) [] [tm]);
   258   in
   259     (case mapfilt_atoms atom_err norm_tm of
   260       [] => (norm_tm, type_of norm_tm, maxidx_of_term norm_tm)
   261     | errs => raise_type (cat_lines errs) [] [norm_tm])
   262   end;
   263 
   264 
   265 
   266 (** infer_types **)         (*exception ERROR*)
   267 
   268 fun infer_types sg types sorts used freeze (ts, T) =
   269   let
   270     val Sg {tsig, ...} = sg;
   271     val show_typ = string_of_typ sg;
   272     val show_term = string_of_term sg;
   273 
   274     fun term_err [] = ""
   275       | term_err [t] = "\nInvolving this term:\n" ^ show_term t
   276       | term_err ts =
   277           "\nInvolving these terms:\n" ^ cat_lines (map show_term ts);
   278 
   279     fun exn_type_msg (msg, Ts, ts) =
   280 	"\nType checking error: " ^ msg ^ "\n" ^
   281 	cat_lines (map show_typ Ts) ^ term_err ts ^ "\n";
   282 
   283     val T' = certify_typ sg T
   284              handle TYPE arg => error (exn_type_msg arg);
   285 
   286     val ct = const_type sg;
   287 
   288     fun warn() =
   289       if length ts > 1 andalso length ts <= !Syntax.ambiguity_level
   290       then (*no warning shown yet*)
   291            writeln "Warning: Currently parsed input \
   292                    \produces more than one parse tree.\n\
   293                    \For more information lower Syntax.ambiguity_level."
   294       else ();
   295 
   296     datatype result = One of int * term * (indexname * typ) list
   297                     | Errs of (string * typ list * term list)list
   298                     | Ambigs of term list;
   299 
   300     fun process_term(res,(t,i)) =
   301        let val (u,tye) = Type.infer_types(tsig,ct,types,sorts,used,freeze,T',t)
   302        in case res of
   303             One(_,t0,_) => Ambigs([u,t0])
   304           | Errs _ => One(i,u,tye)
   305           | Ambigs(us) => Ambigs(u::us)
   306        end
   307        handle TYPE arg => (case res of Errs(errs) => Errs(arg::errs)
   308                                      | _ => res);
   309 
   310   in case foldl process_term (Errs[], ts ~~ (0 upto (length ts - 1))) of
   311        One(res) =>
   312          (if length ts > !Syntax.ambiguity_level
   313           then writeln "Fortunately, only one parse tree is type correct.\n\
   314             \It helps (speed!) if you disambiguate your grammar or your input."
   315           else ();
   316           res)
   317      | Errs(errs) => (warn(); error(cat_lines(map exn_type_msg errs)))
   318      | Ambigs(us) =>
   319          (warn();
   320           let val old_show_brackets = !show_brackets
   321               val dummy = show_brackets := true;
   322               val errs = cat_lines(map show_term us)
   323           in show_brackets := old_show_brackets;
   324              error("Error: More than one term is type correct:\n" ^ errs)
   325           end)
   326   end;
   327 
   328 
   329 (** extend signature **)    (*exception ERROR*)
   330 
   331 (** signature extension functions **)  (*exception ERROR*)
   332 
   333 fun decls_of name_of mfixs =
   334   map (fn (x, y, mx) => (name_of x mx, y)) mfixs;
   335 
   336 
   337 (* add default sort *)
   338 
   339 fun ext_defsort (syn, tsig, ctab) defsort =
   340   (syn, ext_tsig_defsort tsig defsort, ctab);
   341 
   342 
   343 (* add type constructors *)
   344 
   345 fun ext_types (syn, tsig, ctab) types =
   346   (Syntax.extend_type_gram syn types,
   347     ext_tsig_types tsig (decls_of Syntax.type_name types),
   348     ctab);
   349 
   350 
   351 (* add type abbreviations *)
   352 
   353 fun read_abbr syn tsig (t, vs, rhs_src) =
   354   (t, vs, read_raw_typ syn tsig (K None) rhs_src)
   355     handle ERROR => error ("in type abbreviation " ^ t);
   356 
   357 fun ext_abbrs rd_abbr (syn, tsig, ctab) abbrs =
   358   let
   359     fun mfix_of (t, vs, _, mx) = (t, length vs, mx);
   360     val syn1 = Syntax.extend_type_gram syn (map mfix_of abbrs);
   361 
   362     fun decl_of (t, vs, rhs, mx) =
   363       rd_abbr syn1 tsig (Syntax.type_name t mx, vs, rhs);
   364   in
   365     (syn1, ext_tsig_abbrs tsig (map decl_of abbrs), ctab)
   366   end;
   367 
   368 val ext_tyabbrs_i = ext_abbrs (K (K I));
   369 val ext_tyabbrs = ext_abbrs read_abbr;
   370 
   371 
   372 (* add type arities *)
   373 
   374 fun ext_arities (syn, tsig, ctab) arities =
   375   let
   376     val tsig1 = ext_tsig_arities tsig arities;
   377     val log_types = logical_types tsig1;
   378   in
   379     (Syntax.extend_log_types syn log_types, tsig1, ctab)
   380   end;
   381 
   382 
   383 (* add term constants and syntax *)
   384 
   385 fun err_in_const c =
   386   error ("in declaration of constant " ^ quote c);
   387 
   388 fun err_dup_consts cs =
   389   error ("Duplicate declaration of constant(s) " ^ commas_quote cs);
   390 
   391 
   392 fun read_const syn tsig (c, ty_src, mx) =
   393   (c, read_raw_typ syn tsig (K None) ty_src, mx)
   394     handle ERROR => err_in_const (Syntax.const_name c mx);
   395 
   396 fun ext_cnsts rd_const syn_only (syn, tsig, ctab) raw_consts =
   397   let
   398     fun prep_const (c, ty, mx) = (c, varifyT (cert_typ tsig (no_tvars ty)), mx)
   399       handle TYPE (msg, _, _) => (writeln msg; err_in_const (Syntax.const_name c mx));
   400 
   401     val consts = map (prep_const o rd_const syn tsig) raw_consts;
   402     val decls =
   403       if syn_only then []
   404       else filter_out (equal "" o fst) (decls_of Syntax.const_name consts);
   405   in
   406     (Syntax.extend_const_gram syn consts, tsig,
   407       Symtab.extend_new (ctab, decls)
   408         handle Symtab.DUPS cs => err_dup_consts cs)
   409   end;
   410 
   411 val ext_consts_i = ext_cnsts (K (K I)) false;
   412 val ext_consts = ext_cnsts read_const false;
   413 val ext_syntax_i = ext_cnsts (K (K I)) true;
   414 val ext_syntax = ext_cnsts read_const true;
   415 
   416 
   417 (* add type classes *)
   418 
   419 fun const_of_class c = c ^ "_class";
   420 
   421 fun class_of_const c_class =
   422   let
   423     val c = implode (take (size c_class - 6, explode c_class));
   424   in
   425     if const_of_class c = c_class then c
   426     else raise_term ("class_of_const: bad name " ^ quote c_class) []
   427   end;
   428 
   429 
   430 fun ext_classes (syn, tsig, ctab) classes =
   431   let
   432     val names = map fst classes;
   433     val consts =
   434       map (fn c => (const_of_class c, a_itselfT --> propT, NoSyn)) names;
   435   in
   436     ext_consts_i
   437       (Syntax.extend_consts syn names, ext_tsig_classes tsig classes, ctab)
   438       consts
   439   end;
   440 
   441 
   442 (* add to subclass relation *)
   443 
   444 fun ext_classrel (syn, tsig, ctab) pairs =
   445   (syn, ext_tsig_subclass tsig pairs, ctab);
   446 
   447 
   448 (* add to syntax *)
   449 
   450 fun ext_syn extfun (syn, tsig, ctab) args =
   451   (extfun syn args, tsig, ctab);
   452 
   453 
   454 (* build signature *)
   455 
   456 fun ext_stamps stamps name =
   457   let
   458     val stmps = (case stamps of ref "#" :: ss => ss | ss => ss);
   459   in
   460     if exists (equal name o !) stmps then
   461       error ("Theory already contains a " ^ quote name ^ " component")
   462     else ref name :: stmps
   463   end;
   464 
   465 fun make_sign (syn, tsig, ctab) stamps name =
   466   Sg {tsig = tsig, const_tab = ctab, syn = syn,
   467     stamps = ext_stamps stamps name};
   468 
   469 fun extend_sign extfun name decls (Sg {tsig, const_tab, syn, stamps}) =
   470   make_sign (extfun (syn, tsig, const_tab) decls) stamps name;
   471 
   472 
   473 (* the external interfaces *)
   474 
   475 val add_classes   = extend_sign ext_classes "#";
   476 val add_classrel  = extend_sign ext_classrel "#";
   477 val add_defsort   = extend_sign ext_defsort "#";
   478 val add_types     = extend_sign ext_types "#";
   479 val add_tyabbrs   = extend_sign ext_tyabbrs "#";
   480 val add_tyabbrs_i = extend_sign ext_tyabbrs_i "#";
   481 val add_arities   = extend_sign ext_arities "#";
   482 val add_consts    = extend_sign ext_consts "#";
   483 val add_consts_i  = extend_sign ext_consts_i "#";
   484 val add_syntax    = extend_sign ext_syntax "#";
   485 val add_syntax_i  = extend_sign ext_syntax_i "#";
   486 val add_trfuns    = extend_sign (ext_syn Syntax.extend_trfuns) "#";
   487 val add_trrules   = extend_sign (ext_syn Syntax.extend_trrules) "#";
   488 val add_trrules_i = extend_sign (ext_syn Syntax.extend_trrules_i) "#";
   489 
   490 fun add_name name sg = extend_sign K name () sg;
   491 val make_draft = add_name "#";
   492 
   493 
   494 
   495 (** merge signatures **)    (*exception TERM*) (*exception ERROR (* FIXME *)*)
   496 
   497 fun merge (sg1, sg2) =
   498   if subsig (sg2, sg1) then sg1
   499   else if subsig (sg1, sg2) then sg2
   500   else if is_draft sg1 orelse is_draft sg2 then
   501     raise_term "Illegal merge of draft signatures" []
   502   else
   503     (*neither is union already; must form union*)
   504     let
   505       val Sg {tsig = tsig1, const_tab = const_tab1, syn = syn1,
   506         stamps = stamps1} = sg1;
   507       val Sg {tsig = tsig2, const_tab = const_tab2, syn = syn2,
   508         stamps = stamps2} = sg2;
   509 
   510 
   511       val stamps = merge_rev_lists stamps1 stamps2;
   512       val _ =
   513         (case duplicates (stamp_names stamps) of
   514           [] => ()
   515         | dups => raise_term ("Attempt to merge different versions of theories "
   516             ^ commas_quote dups) []);
   517 
   518       val tsig = merge_tsigs (tsig1, tsig2);
   519 
   520       val const_tab = Symtab.merge (op =) (const_tab1, const_tab2)
   521         handle Symtab.DUPS cs =>
   522           raise_term ("Incompatible types for constant(s) " ^ commas_quote cs) [];
   523 
   524       val syn = Syntax.merge_syntaxes syn1 syn2;
   525     in
   526       Sg {tsig = tsig, const_tab = const_tab, syn = syn, stamps = stamps}
   527     end;
   528 
   529 
   530 
   531 (** the Pure signature **)
   532 
   533 val proto_pure =
   534   make_sign (Syntax.pure_syn, tsig0, Symtab.null) [] "#"
   535   |> add_types
   536    (("fun", 2, NoSyn) ::
   537     ("prop", 0, NoSyn) ::
   538     ("itself", 1, NoSyn) ::
   539     Syntax.pure_types)
   540   |> add_classes [(logicC, [])]
   541   |> add_defsort logicS
   542   |> add_arities
   543    [("fun", [logicS, logicS], logicS),
   544     ("prop", [], logicS),
   545     ("itself", [logicS], logicS)]
   546   |> add_syntax Syntax.pure_syntax
   547   |> add_trfuns Syntax.pure_trfuns
   548   |> add_consts
   549    [("==", "['a::{}, 'a] => prop", Mixfix ("(_ ==/ _)", [3, 2], 2)),
   550     ("=?=", "['a::{}, 'a] => prop", Mixfix ("(_ =?=/ _)", [3, 2], 2)),
   551     ("==>", "[prop, prop] => prop", Mixfix ("(_ ==>/ _)", [2, 1], 1)),
   552     ("all", "('a => prop) => prop", Binder ("!!", 0, 0)),
   553     ("TYPE", "'a itself", NoSyn)]
   554   |> add_name "ProtoPure";
   555 
   556 val pure = proto_pure
   557   |> add_syntax Syntax.pure_appl_syntax
   558   |> add_name "Pure";
   559 
   560 val cpure = proto_pure
   561   |> add_syntax Syntax.pure_applC_syntax
   562   |> add_name "CPure";
   563 
   564 end;