data/glr.cc

   1                                                                     -*- C -*-
   2
   3 # C++ GLR skeleton for Bison
   4 # Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
   5
   6 # This program is free software; you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation; either version 2 of the License, or
   9 # (at your option) any later version.
  10
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program; if not, write to the Free Software
  18 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 # 02110-1301  USA
  20
  21
  22 # This skeleton produces a C++ class that encapsulates a C glr parser.
  23 # This is in order to reduce the maintenance burden.  The glr.c
  24 # skeleton is clean and pure enough so that there are no real
  25 # problems.  The C++ interface is the same as that of lalr1.cc.  In
  26 # fact, glr.c can replace yacc.c without the user noticing any
  27 # difference, and similarly for glr.cc replacing lalr1.cc.
  28 #
  29 # The passing of parse-params
  30 #
  31 #   The additional arguments are stored as members of the parser
  32 #   object, yyparser.  The C routines need to carry yyparser
  33 #   throughout the C parser; that easy: just let yyparser become an
  34 #   additional parse-param.  But because the C++ skeleton needs to
  35 #   know the "real" original parse-param, we save them
  36 #   (b4_parse_param_orig).  Note that b4_parse_param is overquoted
  37 #   (and c.m4 strips one level of quotes).  This is a PITA, and
  38 #   explains why there are so many levels of quotes.
  39 #
  40 # The locations
  41 #
  42 #   We use location.cc just like lalr1.cc, but because glr.c stores
  43 #   the locations in a (C++) union, the position and location classes
  44 #   must not have a constructor.  Therefore, contrary to lalr1.cc, we
  45 #   must not define "b4_location_constructors".  As a consequence the
  46 #   user must initialize the first positions (in particular the
  47 #   filename member).
  48
  49 # We require a pure interface using locations.
  50 m4_define([b4_locations_flag], [1])
  51 m4_define([b4_pure_flag],      [1])
  52
  53 # The header is mandatory.
  54 b4_defines_if([],
  55               [b4_fatal([b4_skeleton[: using %%defines is mandatory]])])
  56
  57 m4_include(b4_pkgdatadir/[c++.m4])
  58 m4_include(b4_pkgdatadir/[location.cc])
  59
  60 b4_check_percent_define_variables([[global_tokens_and_yystype]],
  61                                   [[parser_class_name]],
  62                                   [[location_type]],
  63                                   [[filename_type]],
  64                                   [[b4_namespace]],
  65                                   [[b4_define_location_comparison]])
  66
  67 # Save the parse parameters.
  68 m4_define([b4_parse_param_orig], m4_defn([b4_parse_param]))
  69
  70
  71 # b4_yy_symbol_print_generate
  72 # ---------------------------
  73 # Bypass the default implementation to generate the "yy_symbol_print"
  74 # and "yy_symbol_value_print" functions.
  75 m4_define([b4_yy_symbol_print_generate],
  76 [[
  77 /*--------------------.
  78 | Print this symbol.  |
  79 `--------------------*/
  80
  81 ]b4_c_ansi_function_def([yy_symbol_print],
  82     [static void],
  83     [[FILE *],               []],
  84     [[int yytype],           [yytype]],
  85     [[const b4_namespace::b4_parser_class_name::semantic_type *yyvaluep],
  86                              [yyvaluep]],
  87     [[const b4_namespace::b4_parser_class_name::location_type *yylocationp],
  88                              [yylocationp]],
  89     b4_parse_param)[
  90 {
  91 ]b4_parse_param_use[]dnl
  92 [  yyparser.yy_symbol_print_ (yytype, yyvaluep]b4_locations_if([, yylocationp])[);
  93 }
  94 ]])
  95
  96
  97 # Declare yyerror.
  98 m4_append([b4_post_prologue],
  99 [b4_syncline([@oline@], [@ofile@])
 100
 101 b4_c_ansi_function_decl([yyerror],
 102     [static void],
 103     [[b4_namespace::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 104     b4_parse_param,
 105     [[const char* msg], [msg]])])
 106
 107
 108 # Define yyerror.
 109 m4_append([b4_epilogue],
 110 [b4_syncline([@oline@], [@ofile@])[
 111 /*------------------.
 112 | Report an error.  |
 113 `------------------*/
 114
 115 ]b4_c_ansi_function_def([yyerror],
 116     [static void],
 117     [[b4_namespace::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 118     b4_parse_param,
 119     [[const char* msg], [msg]])[
 120 {
 121 ]b4_parse_param_use[]dnl
 122 [  yyparser.error (*yylocationp, msg);
 123 }
 124
 125
 126 namespace ]b4_namespace[
 127 {
 128 ]dnl In this section, the parse param are the original parse_params.
 129 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
 130 [  /// Build a parser object.
 131   ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [
 132     :])[
 133 #if YYDEBUG
 134     ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
 135       yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 136 #endif]b4_parse_param_cons[
 137   {
 138   }
 139
 140   ]b4_parser_class_name::~b4_parser_class_name[ ()
 141   {
 142   }
 143
 144   int
 145   ]b4_parser_class_name[::parse ()
 146   {
 147     return ::yyparse (*this]b4_user_args[);
 148   }
 149
 150 #if YYDEBUG
 151   /*--------------------.
 152   | Print this symbol.  |
 153   `--------------------*/
 154
 155   inline void
 156   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 157                            const semantic_type* yyvaluep, const location_type* yylocationp)
 158   {
 159     /* Pacify ``unused variable'' warnings.  */
 160     YYUSE (yyvaluep);
 161     YYUSE (yylocationp);
 162     switch (yytype)
 163       {
 164   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
 165 [        default:
 166           break;
 167       }
 168   }
 169
 170
 171   void
 172   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 173                            const semantic_type* yyvaluep, const location_type* yylocationp)
 174   {
 175     *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
 176                << ' ' << yytname[yytype] << " ("
 177                << *yylocationp << ": ";
 178     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
 179     *yycdebug_ << ')';
 180   }
 181
 182   std::ostream&
 183   ]b4_parser_class_name[::debug_stream () const
 184   {
 185     return *yycdebug_;
 186   }
 187
 188   void
 189   ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
 190   {
 191     yycdebug_ = &o;
 192   }
 193
 194
 195   ]b4_parser_class_name[::debug_level_type
 196   ]b4_parser_class_name[::debug_level () const
 197   {
 198     return yydebug_;
 199   }
 200
 201   void
 202   ]b4_parser_class_name[::set_debug_level (debug_level_type l)
 203   {
 204     yydebug_ = l;
 205   }
 206
 207 #endif
 208 ]m4_popdef([b4_parse_param])dnl
 209 [} // namespace ]b4_namespace[
 210
 211 ]])
 212
 213
 214 # Let glr.c believe that the user arguments include the parser itself.
 215 m4_ifset([b4_parse_param],
 216 [m4_pushdef([b4_parse_param],
 217             m4_dquote([[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]],]
 218 m4_defn([b4_parse_param])))],
 219 [m4_pushdef([b4_parse_param],
 220             [[[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]]]])
 221 ])
 222 m4_include(b4_pkgdatadir/[glr.c])
 223 m4_popdef([b4_parse_param])
 224
 225 m4_divert_push(0)
 226 @output(b4_spec_defines_file@)
 227 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 228   [2002, 2003, 2004, 2005, 2006])[
 229
 230 /* C++ GLR parser skeleton written by Akim Demaille.  */
 231
 232 #ifndef PARSER_HEADER_H
 233 # define PARSER_HEADER_H
 234
 235 ]m4_ifdef([b4_percent_code_requires],
 236 [[/* Copy the %code "requires" blocks.  */
 237 ]b4_user_code([b4_percent_code_requires])])[
 238
 239 #include <string>
 240 #include <iostream>
 241
 242 /* Using locations.  */
 243 #define YYLSP_NEEDED ]b4_locations_flag[
 244
 245 namespace ]b4_namespace[
 246 {
 247   class position;
 248   class location;
 249 }
 250
 251 #include "location.hh"
 252
 253 /* Enabling traces.  */
 254 #ifndef YYDEBUG
 255 # define YYDEBUG ]b4_debug_flag[
 256 #endif
 257
 258 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 259    If N is 0, then set CURRENT to the empty location which ends
 260    the previous symbol: RHS[0] (always defined).  */
 261
 262 #ifndef YYLLOC_DEFAULT
 263 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 264     do                                                                  \
 265       if (N)                                                            \
 266         {                                                               \
 267           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 268           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 269         }                                                               \
 270       else                                                              \
 271         {                                                               \
 272           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 273         }                                                               \
 274     while (/*CONSTCOND*/ 0)
 275 #endif
 276
 277 namespace ]b4_namespace[
 278 {
 279   /// A Bison parser.
 280   class ]b4_parser_class_name[
 281   {
 282   public:
 283     /// Symbol semantic values.
 284 #ifndef YYSTYPE
 285 ]m4_ifdef([b4_stype],
 286 [    union semantic_type
 287 b4_user_stype
 288         ;],
 289 [m4_if(b4_tag_seen_flag, 0,
 290 [[    typedef int semantic_type;]],
 291 [[    typedef YYSTYPE semantic_type;]])])[
 292 #else
 293     typedef YYSTYPE semantic_type;
 294 #endif
 295     /// Symbol locations.
 296     typedef ]b4_location_type[ location_type;
 297     /// Tokens.
 298     struct token
 299     {
 300       ]b4_token_enums(b4_tokens)[
 301     };
 302     /// Token type.
 303     typedef token::yytokentype token_type;
 304
 305     /// Build a parser object.
 306     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 307     virtual ~]b4_parser_class_name[ ();
 308
 309     /// Parse.
 310     /// \returns  0 iff parsing succeeded.
 311     virtual int parse ();
 312
 313     /// The current debugging stream.
 314     std::ostream& debug_stream () const;
 315     /// Set the current debugging stream.
 316     void set_debug_stream (std::ostream &);
 317
 318     /// Type for debugging levels.
 319     typedef int debug_level_type;
 320     /// The current debugging level.
 321     debug_level_type debug_level () const;
 322     /// Set the current debugging level.
 323     void set_debug_level (debug_level_type l);
 324
 325   private:
 326
 327   public:
 328     /// Report a syntax error.
 329     /// \param loc    where the syntax error is found.
 330     /// \param msg    a description of the syntax error.
 331     virtual void error (const location_type& loc, const std::string& msg);
 332   private:
 333
 334 #if YYDEBUG
 335   public:
 336     /// \brief Report a symbol value on the debug stream.
 337     /// \param yytype       The token type.
 338     /// \param yyvaluep     Its semantic value.
 339     /// \param yylocationp  Its location.
 340     virtual void yy_symbol_value_print_ (int yytype,
 341                                          const semantic_type* yyvaluep,
 342                                          const location_type* yylocationp);
 343     /// \brief Report a symbol on the debug stream.
 344     /// \param yytype       The token type.
 345     /// \param yyvaluep     Its semantic value.
 346     /// \param yylocationp  Its location.
 347     virtual void yy_symbol_print_ (int yytype,
 348                                    const semantic_type* yyvaluep,
 349                                    const location_type* yylocationp);
 350   private:
 351     /* Debugging.  */
 352     int yydebug_;
 353     std::ostream* yycdebug_;
 354 #endif
 355
 356
 357     /// \brief Reclaim the memory associated to a symbol.
 358     /// \param yymsg        Why this token is reclaimed.
 359     /// \param yytype       The symbol type.
 360     /// \param yyvaluep     Its semantic value.
 361     /// \param yylocationp  Its location.
 362     inline void yydestruct_ (const char* yymsg,
 363                              int yytype,
 364                              semantic_type* yyvaluep,
 365                              location_type* yylocationp);
 366
 367 ]b4_parse_param_vars[
 368   };
 369
 370 ]dnl Redirections for glr.c.
 371 m4_ifset([b4_global_tokens_and_yystype],
 372 [b4_token_defines(b4_tokens)])
 373 [
 374 #ifndef YYSTYPE
 375 # define YYSTYPE ]b4_namespace[::]b4_parser_class_name[::semantic_type
 376 #endif
 377 #ifndef YYLTYPE
 378 # define YYLTYPE ]b4_namespace[::]b4_parser_class_name[::location_type
 379 #endif
 380
 381 }
 382
 383 ]m4_ifdef([b4_percent_code_provides],
 384 [[/* Copy the %code "provides" blocks.  */
 385 ]b4_user_code([b4_percent_code_provides])])[]dnl
 386
 387 [#endif /* ! defined PARSER_HEADER_H */]
 388 m4_divert_pop(0)