src/Pure/sign.ML
author nipkow
Fri Mar 17 15:52:55 1995 +0100 (1995-03-17)
changeset 963 7a78fda77104
parent 959 35c2e5e114c4
child 986 c978bb4e9a55
permissions -rw-r--r--
Corrected a silly old bug in merge_tsigs.
Rewrote a lot of Nimmermann's code.
     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 is_draft: sg -> bool
    24     val const_type: sg -> string -> typ option
    25     val classes: sg -> class list
    26     val subsort: sg -> sort * sort -> bool
    27     val norm_sort: sg -> sort -> sort
    28     val print_sg: sg -> unit
    29     val pretty_sg: sg -> Pretty.T
    30     val pprint_sg: sg -> pprint_args -> unit
    31     val pretty_term: sg -> term -> Pretty.T
    32     val pretty_typ: sg -> typ -> Pretty.T
    33     val pretty_sort: sort -> Pretty.T
    34     val string_of_term: sg -> term -> string
    35     val string_of_typ: sg -> typ -> string
    36     val pprint_term: sg -> term -> pprint_args -> unit
    37     val pprint_typ: sg -> typ -> pprint_args -> unit
    38     val certify_typ: sg -> typ -> typ
    39     val certify_term: sg -> term -> term * typ * int
    40     val read_typ: sg * (indexname -> sort option) -> string -> typ
    41     val infer_types: sg -> (indexname -> typ option) ->
    42       (indexname -> sort option) -> string list -> bool
    43       -> term list * typ -> int * term * (indexname * typ) list
    44     val add_classes: (class * class list) list -> sg -> sg
    45     val add_classrel: (class * class) list -> sg -> sg
    46     val add_defsort: sort -> sg -> sg
    47     val add_types: (string * int * mixfix) list -> sg -> sg
    48     val add_tyabbrs: (string * string list * string * mixfix) list -> sg -> sg
    49     val add_tyabbrs_i: (string * string list * typ * mixfix) list -> sg -> sg
    50     val add_arities: (string * sort list * sort) list -> sg -> sg
    51     val add_consts: (string * string * mixfix) list -> sg -> sg
    52     val add_consts_i: (string * typ * mixfix) list -> sg -> sg
    53     val add_syntax: (string * string * mixfix) list -> sg -> sg
    54     val add_syntax_i: (string * typ * mixfix) list -> sg -> sg
    55     val add_trfuns:
    56       (string * (ast list -> ast)) list *
    57       (string * (term list -> term)) list *
    58       (string * (term list -> term)) list *
    59       (string * (ast list -> ast)) list -> sg -> sg
    60     val add_trrules: xrule list -> sg -> sg
    61     val add_name: string -> sg -> sg
    62     val make_draft: sg -> sg
    63     val merge: sg * sg -> sg
    64     val proto_pure: sg
    65     val pure: sg
    66     val cpure: sg
    67     val const_of_class: class -> string
    68     val class_of_const: string -> class
    69   end
    70 end;
    71 
    72 functor SignFun(structure Syntax: SYNTAX and Type: TYPE): SIGN =
    73 struct
    74 
    75 structure Symtab = Type.Symtab;
    76 structure Syntax = Syntax;
    77 structure BasicSyntax: BASIC_SYNTAX = Syntax;
    78 structure Pretty = Syntax.Pretty;
    79 structure Type = Type;
    80 open BasicSyntax Type;
    81 
    82 
    83 (** datatype sg **)
    84 
    85 (*the "ref" in stamps ensures that no two signatures are identical -- it is
    86   impossible to forge a signature*)
    87 
    88 datatype sg =
    89   Sg of {
    90     tsig: type_sig,                 (*order-sorted signature of types*)
    91     const_tab: typ Symtab.table,    (*types of constants*)
    92     syn: Syntax.syntax,             (*syntax for parsing and printing*)
    93     stamps: string ref list};       (*unique theory indentifier*)
    94 
    95 fun rep_sg (Sg args) = args;
    96 val tsig_of = #tsig o rep_sg;
    97 
    98 
    99 (* stamps *)
   100 
   101 fun is_draft (Sg {stamps = ref "#" :: _, ...}) = true
   102   | is_draft _ = false;
   103 
   104 fun subsig (Sg {stamps = s1, ...}, Sg {stamps = s2, ...}) = s1 subset s2;
   105 
   106 fun eq_sg (Sg {stamps = s1, ...}, Sg {stamps = s2, ...}) = eq_set (s1, s2);
   107 
   108 
   109 (* consts *)
   110 
   111 fun const_type (Sg {const_tab, ...}) c =
   112   Symtab.lookup (const_tab, c);
   113 
   114 
   115 (* classes and sorts *)
   116 
   117 val classes = #classes o Type.rep_tsig o tsig_of;
   118 
   119 val subsort = Type.subsort o tsig_of;
   120 val norm_sort = Type.norm_sort o tsig_of;
   121 
   122 fun pretty_sort [c] = Pretty.str c
   123   | pretty_sort cs = Pretty.str_list "{" "}" cs;
   124 
   125 
   126 
   127 (** print signature **)
   128 
   129 val stamp_names = rev o map !;
   130 
   131 fun print_sg sg =
   132   let
   133     fun prt_typ syn ty = Pretty.quote (Syntax.pretty_typ syn ty);
   134 
   135     fun pretty_subclass (cl, cls) = Pretty.block
   136       [Pretty.str (cl ^ " <"), Pretty.brk 1, pretty_sort cls];
   137 
   138     fun pretty_default cls = Pretty.block
   139       [Pretty.str "default:", Pretty.brk 1, pretty_sort cls];
   140 
   141     fun pretty_ty (ty, n) = Pretty.str (ty ^ " " ^ string_of_int n);
   142 
   143     fun pretty_abbr syn (ty, (vs, rhs)) = Pretty.block
   144       [prt_typ syn (Type (ty, map (fn v => TVar ((v, 0), [])) vs)),
   145         Pretty.str " =", Pretty.brk 1, prt_typ syn rhs];
   146 
   147     fun pretty_arity ty (cl, []) = Pretty.block
   148           [Pretty.str (ty ^ " ::"), Pretty.brk 1, Pretty.str cl]
   149       | pretty_arity ty (cl, srts) = Pretty.block
   150           [Pretty.str (ty ^ " ::"), Pretty.brk 1,
   151             Pretty.list "(" ")" (map pretty_sort srts),
   152             Pretty.brk 1, Pretty.str cl];
   153 
   154     fun pretty_arities (ty, ars) = map (pretty_arity ty) ars;
   155 
   156     fun pretty_const syn (c, ty) = Pretty.block
   157       [Pretty.str (quote c ^ " ::"), Pretty.brk 1, prt_typ syn ty];
   158 
   159 
   160     val Sg {tsig, const_tab, syn, stamps} = sg;
   161     val {classes, subclass, default, tycons, abbrs, arities} = rep_tsig tsig;
   162   in
   163     Pretty.writeln (Pretty.strs ("stamps:" :: stamp_names stamps));
   164     Pretty.writeln (Pretty.strs ("classes:" :: classes));
   165     Pretty.writeln (Pretty.big_list "subclass:"
   166                       (map pretty_subclass subclass));
   167     Pretty.writeln (pretty_default default);
   168     Pretty.writeln (Pretty.big_list "types:" (map pretty_ty tycons));
   169     Pretty.writeln (Pretty.big_list "abbrs:" (map (pretty_abbr syn) abbrs));
   170     Pretty.writeln (Pretty.big_list "arities:"
   171                       (flat (map pretty_arities arities)));
   172     Pretty.writeln (Pretty.big_list "consts:"
   173                       (map (pretty_const syn) (Symtab.dest const_tab)))
   174   end;
   175 
   176 
   177 fun pretty_sg (Sg {stamps, ...}) =
   178   Pretty.str_list "{" "}" (stamp_names stamps);
   179 
   180 val pprint_sg = Pretty.pprint o pretty_sg;
   181 
   182 
   183 
   184 (** pretty printing of terms and types **)
   185 
   186 fun pretty_term (Sg {syn, stamps, ...}) =
   187   let val curried = "CPure" mem (map ! stamps);
   188   in Syntax.pretty_term curried syn end;
   189 
   190 fun pretty_typ (Sg {syn, ...}) = Syntax.pretty_typ syn;
   191 
   192 fun string_of_term (Sg {syn, stamps, ...}) = 
   193   let val curried = "CPure" mem (map ! stamps);
   194   in Syntax.string_of_term curried syn end;
   195 
   196 fun string_of_typ (Sg {syn, ...}) = Syntax.string_of_typ syn;
   197 
   198 fun pprint_term sg = Pretty.pprint o Pretty.quote o (pretty_term sg);
   199 fun pprint_typ sg = Pretty.pprint o Pretty.quote o (pretty_typ sg);
   200 
   201 
   202 
   203 (** read types **)  (*exception ERROR*)
   204 
   205 fun err_in_type s =
   206   error ("The error(s) above occurred in type " ^ quote s);
   207 
   208 fun read_raw_typ syn tsig sort_of str =
   209   Syntax.read_typ syn (fn x => if_none (sort_of x) (defaultS tsig)) str
   210     handle ERROR => err_in_type str;
   211 
   212 (*read and certify typ wrt a signature*)
   213 fun read_typ (Sg {tsig, syn, ...}, sort_of) str =
   214   cert_typ tsig (read_raw_typ syn tsig sort_of str)
   215     handle TYPE (msg, _, _) => (writeln msg; err_in_type str);
   216 
   217 
   218 
   219 (** certify types and terms **)   (*exception TYPE*)
   220 
   221 fun certify_typ (Sg {tsig, ...}) ty = cert_typ tsig ty;
   222 
   223 
   224 fun mapfilt_atoms f (Abs (_, _, t)) = mapfilt_atoms f t
   225   | mapfilt_atoms f (t $ u) = mapfilt_atoms f t @ mapfilt_atoms f u
   226   | mapfilt_atoms f a = (case f a of Some y => [y] | None => []);
   227 
   228 fun certify_term (sg as Sg {tsig, ...}) tm =
   229   let
   230     fun valid_const a T =
   231       (case const_type sg a of
   232         Some U => typ_instance (tsig, T, U)
   233       | _ => false);
   234 
   235     fun atom_err (Const (a, T)) =
   236           if valid_const a T then None
   237           else Some ("Illegal type for constant " ^ quote a ^ " :: " ^
   238             quote (string_of_typ sg T))
   239       | atom_err (Var ((x, i), _)) =
   240           if i < 0 then Some ("Negative index for Var " ^ quote x) else None
   241       | atom_err _ = None;
   242 
   243     val norm_tm =
   244       (case it_term_types (typ_errors tsig) (tm, []) of
   245         [] => map_term_types (norm_typ tsig) tm
   246       | errs => raise_type (cat_lines errs) [] [tm]);
   247   in
   248     (case mapfilt_atoms atom_err norm_tm of
   249       [] => (norm_tm, type_of norm_tm, maxidx_of_term norm_tm)
   250     | errs => raise_type (cat_lines errs) [] [norm_tm])
   251   end;
   252 
   253 
   254 
   255 (** infer_types **)         (*exception ERROR*)
   256 
   257 fun infer_types sg types sorts used freeze (ts, T) =
   258   let
   259     val Sg {tsig, ...} = sg;
   260     val show_typ = string_of_typ sg;
   261     val show_term = string_of_term sg;
   262 
   263     fun term_err [] = ""
   264       | term_err [t] = "\nInvolving this term:\n" ^ show_term t
   265       | term_err ts = 
   266           "\nInvolving these terms:\n" ^ cat_lines (map show_term ts);
   267 
   268     fun exn_type_msg (msg, Ts, ts) =
   269 	"\nType checking error: " ^ msg ^ "\n" ^
   270 	cat_lines (map show_typ Ts) ^ term_err ts ^ "\n";
   271 
   272     val T' = certify_typ sg T
   273              handle TYPE arg => error (exn_type_msg arg);
   274 
   275     val ct = const_type sg;
   276 
   277     fun warn() =
   278       if length ts > 1 andalso length ts <= !Syntax.ambiguity_level
   279       then (*no warning shown yet*)
   280            writeln "Warning: Currently parsed input \
   281                    \produces more than one parse tree.\n\
   282                    \For more information lower Syntax.ambiguity_level."
   283       else ();
   284 
   285     datatype result = One of int * term * (indexname * typ) list
   286                     | Errs of (string * typ list * term list)list
   287                     | Ambigs of term list;
   288 
   289     fun process_term(res,(t,i)) =
   290        let val (u,tye) = Type.infer_types(tsig,ct,types,sorts,used,freeze,T',t)
   291        in case res of
   292             One(_,t0,_) => Ambigs([u,t0])
   293           | Errs _ => One(i,u,tye)
   294           | Ambigs(us) => Ambigs(u::us)
   295        end
   296        handle TYPE arg => (case res of Errs(errs) => Errs(arg::errs)
   297                                      | _ => res);
   298 
   299   in case foldl process_term (Errs[], ts ~~ (0 upto (length ts - 1))) of
   300        One(res) =>
   301          (if length ts > !Syntax.ambiguity_level
   302           then writeln "Fortunately, only one parse tree is type correct.\n\
   303             \It helps (speed!) if you disambiguate your grammar or your input."
   304           else ();
   305           res)
   306      | Errs(errs) => (warn(); error(cat_lines(map exn_type_msg errs)))
   307      | Ambigs(us) =>
   308          (warn();
   309           let val old_show_brackets = !show_brackets
   310               val _ = show_brackets := true;
   311               val errs = cat_lines(map show_term us)
   312           in show_brackets := old_show_brackets;
   313              error("Error: More than one term is type correct:\n" ^ errs)
   314           end)
   315   end;
   316 
   317 
   318 (** extend signature **)    (*exception ERROR*)
   319 
   320 (** signature extension functions **)  (*exception ERROR*)
   321 
   322 fun decls_of name_of mfixs =
   323   map (fn (x, y, mx) => (name_of x mx, y)) mfixs;
   324 
   325 
   326 (* add default sort *)
   327 
   328 fun ext_defsort (syn, tsig, ctab) defsort =
   329   (syn, ext_tsig_defsort tsig defsort, ctab);
   330 
   331 
   332 (* add type constructors *)
   333 
   334 fun ext_types (syn, tsig, ctab) types =
   335   (Syntax.extend_type_gram syn types,
   336     ext_tsig_types tsig (decls_of Syntax.type_name types),
   337     ctab);
   338 
   339 
   340 (* add type abbreviations *)
   341 
   342 fun read_abbr syn tsig (t, vs, rhs_src) =
   343   (t, vs, read_raw_typ syn tsig (K None) rhs_src)
   344     handle ERROR => error ("in type abbreviation " ^ t);
   345 
   346 fun ext_abbrs rd_abbr (syn, tsig, ctab) abbrs =
   347   let
   348     fun mfix_of (t, vs, _, mx) = (t, length vs, mx);
   349     val syn1 = Syntax.extend_type_gram syn (map mfix_of abbrs);
   350 
   351     fun decl_of (t, vs, rhs, mx) =
   352       rd_abbr syn1 tsig (Syntax.type_name t mx, vs, rhs);
   353   in
   354     (syn1, ext_tsig_abbrs tsig (map decl_of abbrs), ctab)
   355   end;
   356 
   357 val ext_tyabbrs_i = ext_abbrs (K (K I));
   358 val ext_tyabbrs = ext_abbrs read_abbr;
   359 
   360 
   361 (* add type arities *)
   362 
   363 fun ext_arities (syn, tsig, ctab) arities =
   364   let
   365     val tsig1 = ext_tsig_arities tsig arities;
   366     val log_types = logical_types tsig1;
   367   in
   368     (Syntax.extend_log_types syn log_types, tsig1, ctab)
   369   end;
   370 
   371 
   372 (* add term constants and syntax *)
   373 
   374 fun err_in_const c =
   375   error ("in declaration of constant " ^ quote c);
   376 
   377 fun err_dup_consts cs =
   378   error ("Duplicate declaration of constant(s) " ^ commas_quote cs);
   379 
   380 
   381 fun read_const syn tsig (c, ty_src, mx) =
   382   (c, read_raw_typ syn tsig (K None) ty_src, mx)
   383     handle ERROR => err_in_const (Syntax.const_name c mx);
   384 
   385 fun ext_cnsts rd_const syn_only (syn, tsig, ctab) raw_consts =
   386   let
   387     fun prep_const (c, ty, mx) = (c, varifyT (cert_typ tsig (no_tvars ty)), mx)
   388       handle TYPE (msg, _, _) => (writeln msg; err_in_const (Syntax.const_name c mx));
   389 
   390     val consts = map (prep_const o rd_const syn tsig) raw_consts;
   391     val decls =
   392       if syn_only then []
   393       else filter_out (equal "" o fst) (decls_of Syntax.const_name consts);
   394   in
   395     (Syntax.extend_const_gram syn consts, tsig,
   396       Symtab.extend_new (ctab, decls)
   397         handle Symtab.DUPS cs => err_dup_consts cs)
   398   end;
   399 
   400 val ext_consts_i = ext_cnsts (K (K I)) false;
   401 val ext_consts = ext_cnsts read_const false;
   402 val ext_syntax_i = ext_cnsts (K (K I)) true;
   403 val ext_syntax = ext_cnsts read_const true;
   404 
   405 
   406 (* add type classes *)
   407 
   408 fun const_of_class c = c ^ "_class";
   409 
   410 fun class_of_const c_class =
   411   let
   412     val c = implode (take (size c_class - 6, explode c_class));
   413   in
   414     if const_of_class c = c_class then c
   415     else raise_term ("class_of_const: bad name " ^ quote c_class) []
   416   end;
   417 
   418 
   419 fun ext_classes (syn, tsig, ctab) classes =
   420   let
   421     val names = map fst classes;
   422     val consts =
   423       map (fn c => (const_of_class c, a_itselfT --> propT, NoSyn)) names;
   424   in
   425     ext_consts_i
   426       (Syntax.extend_consts syn names, ext_tsig_classes tsig classes, ctab)
   427       consts
   428   end;
   429 
   430 
   431 (* add to subclass relation *)
   432 
   433 fun ext_classrel (syn, tsig, ctab) pairs =
   434   (syn, ext_tsig_subclass tsig pairs, ctab);
   435 
   436 
   437 (* add syntactic translations *)
   438 
   439 fun ext_trfuns (syn, tsig, ctab) trfuns =
   440   (Syntax.extend_trfuns syn trfuns, tsig, ctab);
   441 
   442 fun ext_trrules (syn, tsig, ctab) xrules =
   443   (Syntax.extend_trrules syn xrules, tsig, ctab);
   444 
   445 
   446 (* build signature *)
   447 
   448 fun ext_stamps stamps name =
   449   let
   450     val stmps = (case stamps of ref "#" :: ss => ss | ss => ss);
   451   in
   452     if exists (equal name o !) stmps then
   453       error ("Theory already contains a " ^ quote name ^ " component")
   454     else ref name :: stmps
   455   end;
   456 
   457 fun make_sign (syn, tsig, ctab) stamps name =
   458   Sg {tsig = tsig, const_tab = ctab, syn = syn,
   459     stamps = ext_stamps stamps name};
   460 
   461 fun extend_sign extfun name decls (Sg {tsig, const_tab, syn, stamps}) =
   462   make_sign (extfun (syn, tsig, const_tab) decls) stamps name;
   463 
   464 
   465 (* the external interfaces *)
   466 
   467 val add_classes   = extend_sign ext_classes "#";
   468 val add_classrel  = extend_sign ext_classrel "#";
   469 val add_defsort   = extend_sign ext_defsort "#";
   470 val add_types     = extend_sign ext_types "#";
   471 val add_tyabbrs   = extend_sign ext_tyabbrs "#";
   472 val add_tyabbrs_i = extend_sign ext_tyabbrs_i "#";
   473 val add_arities   = extend_sign ext_arities "#";
   474 val add_consts    = extend_sign ext_consts "#";
   475 val add_consts_i  = extend_sign ext_consts_i "#";
   476 val add_syntax    = extend_sign ext_syntax "#";
   477 val add_syntax_i  = extend_sign ext_syntax_i "#";
   478 val add_trfuns    = extend_sign ext_trfuns "#";
   479 val add_trrules   = extend_sign ext_trrules "#";
   480 
   481 fun add_name name sg = extend_sign K name () sg;
   482 val make_draft = add_name "#";
   483 
   484 
   485 
   486 (** merge signatures **)    (*exception TERM*) (*exception ERROR (* FIXME *)*)
   487 
   488 fun merge (sg1, sg2) =
   489   if subsig (sg2, sg1) then sg1
   490   else if subsig (sg1, sg2) then sg2
   491   else if is_draft sg1 orelse is_draft sg2 then
   492     raise_term "Illegal merge of draft signatures" []
   493   else
   494     (*neither is union already; must form union*)
   495     let
   496       val Sg {tsig = tsig1, const_tab = const_tab1, syn = syn1,
   497         stamps = stamps1} = sg1;
   498       val Sg {tsig = tsig2, const_tab = const_tab2, syn = syn2,
   499         stamps = stamps2} = sg2;
   500 
   501 
   502       val stamps = merge_rev_lists stamps1 stamps2;
   503       val _ =
   504         (case duplicates (stamp_names stamps) of
   505           [] => ()
   506         | dups => raise_term ("Attempt to merge different versions of theories "
   507             ^ commas_quote dups) []);
   508 
   509       val tsig = merge_tsigs (tsig1, tsig2);
   510 
   511       val const_tab = Symtab.merge (op =) (const_tab1, const_tab2)
   512         handle Symtab.DUPS cs =>
   513           raise_term ("Incompatible types for constant(s) " ^ commas_quote cs) [];
   514 
   515       val syn = Syntax.merge_syntaxes syn1 syn2;
   516     in
   517       Sg {tsig = tsig, const_tab = const_tab, syn = syn, stamps = stamps}
   518     end;
   519 
   520 
   521 
   522 (** the Pure signature **)
   523 
   524 val proto_pure =
   525   make_sign (Syntax.pure_syn, tsig0, Symtab.null) [] "#"
   526   |> add_types
   527    (("fun", 2, NoSyn) ::
   528     ("prop", 0, NoSyn) ::
   529     ("itself", 1, NoSyn) ::
   530     Syntax.pure_types)
   531   |> add_classes [(logicC, [])]
   532   |> add_defsort logicS
   533   |> add_arities
   534    [("fun", [logicS, logicS], logicS),
   535     ("prop", [], logicS),
   536     ("itself", [logicS], logicS)]
   537   |> add_syntax Syntax.pure_syntax
   538   |> add_trfuns Syntax.pure_trfuns
   539   |> add_consts
   540    [("==", "['a::{}, 'a] => prop", Mixfix ("(_ ==/ _)", [3, 2], 2)),
   541     ("=?=", "['a::{}, 'a] => prop", Mixfix ("(_ =?=/ _)", [3, 2], 2)),
   542     ("==>", "[prop, prop] => prop", Mixfix ("(_ ==>/ _)", [2, 1], 1)),
   543     ("all", "('a => prop) => prop", Binder ("!!", 0, 0)),
   544     ("TYPE", "'a itself", NoSyn)]
   545   |> add_name "ProtoPure";
   546 
   547 val pure = proto_pure
   548   |> add_syntax
   549    [("_appl",     "[('b => 'a), args] => logic",    Mixfix ("(1_/(1'(_')))",
   550                                                     [max_pri, 0], max_pri)),
   551     ("_appl",     "[('b => 'a), args] => aprop",    Mixfix ("(1_/(1'(_')))",
   552                                                     [max_pri, 0], max_pri))]
   553   |> add_name "Pure";
   554 
   555 val cpure = proto_pure
   556   |> add_syntax
   557    [("_applC",     "[('b => 'a), 'c] => logic",     Mixfix ("(1_ (1_))",
   558                                                     [max_pri-1, max_pri],
   559                                                     max_pri-1)),
   560     ("_applC",     "[('b => 'a), 'c] => aprop",     Mixfix ("(1_ (1_))",
   561                                                     [max_pri-1, max_pri],
   562                                                     max_pri-1))]
   563   |> add_name "CPure";
   564 
   565 end;