data/glr.cc

   1                                                                     -*- C -*-
   2
   3 # C++ GLR skeleton for Bison
   4 # Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation,
   5 # Inc.
   6
   7 # This program is free software: you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation, either version 3 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19
  20
  21 # This skeleton produces a C++ class that encapsulates a C glr parser.
  22 # This is in order to reduce the maintenance burden.  The glr.c
  23 # skeleton is clean and pure enough so that there are no real
  24 # problems.  The C++ interface is the same as that of lalr1.cc.  In
  25 # fact, glr.c can replace yacc.c without the user noticing any
  26 # difference, and similarly for glr.cc replacing lalr1.cc.
  27 #
  28 # The passing of parse-params
  29 #
  30 #   The additional arguments are stored as members of the parser
  31 #   object, yyparser.  The C routines need to carry yyparser
  32 #   throughout the C parser; that easy: just let yyparser become an
  33 #   additional parse-param.  But because the C++ skeleton needs to
  34 #   know the "real" original parse-param, we save them
  35 #   (b4_parse_param_orig).  Note that b4_parse_param is overquoted
  36 #   (and c.m4 strips one level of quotes).  This is a PITA, and
  37 #   explains why there are so many levels of quotes.
  38 #
  39 # The locations
  40 #
  41 #   We use location.cc just like lalr1.cc, but because glr.c stores
  42 #   the locations in a (C++) union, the position and location classes
  43 #   must not have a constructor.  Therefore, contrary to lalr1.cc, we
  44 #   must not define "b4_location_constructors".  As a consequence the
  45 #   user must initialize the first positions (in particular the
  46 #   filename member).
  47
  48 # We require a pure interface using locations.
  49 m4_define([b4_locations_flag], [1])
  50 m4_define([b4_pure_flag],      [1])
  51
  52 # The header is mandatory.
  53 b4_defines_if([],
  54               [b4_fatal([b4_skeleton[: using %%defines is mandatory]])])
  55
  56 m4_include(b4_pkgdatadir/[c++.m4])
  57 m4_include(b4_pkgdatadir/[location.cc])
  58
  59 m4_define([b4_parser_class_name],
  60           [b4_percent_define_get([[parser_class_name]])])
  61 m4_define([b4_namespace],
  62           [b4_percent_define_get([[namespace]])])
  63
  64 # Save the parse parameters.
  65 m4_define([b4_parse_param_orig], m4_defn([b4_parse_param]))
  66
  67
  68 # b4_yy_symbol_print_generate
  69 # ---------------------------
  70 # Bypass the default implementation to generate the "yy_symbol_print"
  71 # and "yy_symbol_value_print" functions.
  72 m4_define([b4_yy_symbol_print_generate],
  73 [[
  74 /*--------------------.
  75 | Print this symbol.  |
  76 `--------------------*/
  77
  78 ]b4_c_ansi_function_def([yy_symbol_print],
  79     [static void],
  80     [[FILE *],               []],
  81     [[int yytype],           [yytype]],
  82     [[const b4_namespace::b4_parser_class_name::semantic_type *yyvaluep],
  83                              [yyvaluep]],
  84     [[const b4_namespace::b4_parser_class_name::location_type *yylocationp],
  85                              [yylocationp]],
  86     b4_parse_param)[
  87 {
  88 ]b4_parse_param_use[]dnl
  89 [  yyparser.yy_symbol_print_ (yytype, yyvaluep]b4_locations_if([, yylocationp])[);
  90 }
  91 ]])
  92
  93
  94 # Declare yyerror.
  95 m4_append([b4_post_prologue],
  96 [b4_syncline([@oline@], [@ofile@])
  97
  98 b4_c_ansi_function_decl([yyerror],
  99     [static void],
 100     [[b4_namespace::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 101     b4_parse_param,
 102     [[const char* msg], [msg]])])
 103
 104
 105 # Define yyerror.
 106 m4_append([b4_epilogue],
 107 [b4_syncline([@oline@], [@ofile@])[
 108 /*------------------.
 109 | Report an error.  |
 110 `------------------*/
 111
 112 ]b4_c_ansi_function_def([yyerror],
 113     [static void],
 114     [[b4_namespace::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 115     b4_parse_param,
 116     [[const char* msg], [msg]])[
 117 {
 118 ]b4_parse_param_use[]dnl
 119 [  yyparser.error (*yylocationp, msg);
 120 }
 121
 122
 123 namespace ]b4_namespace[
 124 {
 125 ]dnl In this section, the parse param are the original parse_params.
 126 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
 127 [  /// Build a parser object.
 128   ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [
 129     :])[
 130 #if YYDEBUG
 131     ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
 132       yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 133 #endif]b4_parse_param_cons[
 134   {
 135   }
 136
 137   ]b4_parser_class_name::~b4_parser_class_name[ ()
 138   {
 139   }
 140
 141   int
 142   ]b4_parser_class_name[::parse ()
 143   {
 144     return ::yyparse (*this]b4_user_args[);
 145   }
 146
 147 #if YYDEBUG
 148   /*--------------------.
 149   | Print this symbol.  |
 150   `--------------------*/
 151
 152   inline void
 153   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 154                            const semantic_type* yyvaluep, const location_type* yylocationp)
 155   {
 156     /* Pacify ``unused variable'' warnings.  */
 157     YYUSE (yyvaluep);
 158     YYUSE (yylocationp);
 159     switch (yytype)
 160       {
 161   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
 162 [        default:
 163           break;
 164       }
 165   }
 166
 167
 168   void
 169   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 170                            const semantic_type* yyvaluep, const location_type* yylocationp)
 171   {
 172     *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
 173                << ' ' << yytname[yytype] << " ("
 174                << *yylocationp << ": ";
 175     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
 176     *yycdebug_ << ')';
 177   }
 178
 179   std::ostream&
 180   ]b4_parser_class_name[::debug_stream () const
 181   {
 182     return *yycdebug_;
 183   }
 184
 185   void
 186   ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
 187   {
 188     yycdebug_ = &o;
 189   }
 190
 191
 192   ]b4_parser_class_name[::debug_level_type
 193   ]b4_parser_class_name[::debug_level () const
 194   {
 195     return yydebug_;
 196   }
 197
 198   void
 199   ]b4_parser_class_name[::set_debug_level (debug_level_type l)
 200   {
 201     yydebug_ = l;
 202   }
 203
 204 #endif
 205 ]m4_popdef([b4_parse_param])dnl
 206 [} // namespace ]b4_namespace[
 207
 208 ]])
 209
 210
 211 # Let glr.c believe that the user arguments include the parser itself.
 212 m4_ifset([b4_parse_param],
 213 [m4_pushdef([b4_parse_param],
 214             m4_dquote([[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]],]
 215 m4_defn([b4_parse_param])))],
 216 [m4_pushdef([b4_parse_param],
 217             [[[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]]]])
 218 ])
 219 m4_include(b4_pkgdatadir/[glr.c])
 220 m4_popdef([b4_parse_param])
 221
 222 m4_divert_push(0)
 223 @output(b4_spec_defines_file@)
 224 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 225   [2002, 2003, 2004, 2005, 2006])[
 226
 227 /* C++ GLR parser skeleton written by Akim Demaille.  */
 228
 229 #ifndef PARSER_HEADER_H
 230 # define PARSER_HEADER_H
 231
 232 ]b4_percent_code_get([[requires]])[
 233
 234 #include <string>
 235 #include <iostream>
 236
 237 /* Using locations.  */
 238 #define YYLSP_NEEDED ]b4_locations_flag[
 239
 240 namespace ]b4_namespace[
 241 {
 242   class position;
 243   class location;
 244 }
 245
 246 #include "location.hh"
 247
 248 /* Enabling traces.  */
 249 #ifndef YYDEBUG
 250 # define YYDEBUG ]b4_debug_flag[
 251 #endif
 252
 253 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 254    If N is 0, then set CURRENT to the empty location which ends
 255    the previous symbol: RHS[0] (always defined).  */
 256
 257 #ifndef YYLLOC_DEFAULT
 258 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 259     do                                                                  \
 260       if (N)                                                            \
 261         {                                                               \
 262           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 263           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 264         }                                                               \
 265       else                                                              \
 266         {                                                               \
 267           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 268         }                                                               \
 269     while (/*CONSTCOND*/ 0)
 270 #endif
 271
 272 namespace ]b4_namespace[
 273 {
 274   /// A Bison parser.
 275   class ]b4_parser_class_name[
 276   {
 277   public:
 278     /// Symbol semantic values.
 279 #ifndef YYSTYPE
 280 ]m4_ifdef([b4_stype],
 281 [    union semantic_type
 282     {
 283 b4_user_stype
 284     };],
 285 [m4_if(b4_tag_seen_flag, 0,
 286 [[    typedef int semantic_type;]],
 287 [[    typedef YYSTYPE semantic_type;]])])[
 288 #else
 289     typedef YYSTYPE semantic_type;
 290 #endif
 291     /// Symbol locations.
 292     typedef ]b4_percent_define_get([[location_type]])[ location_type;
 293     /// Tokens.
 294     struct token
 295     {
 296       ]b4_token_enums(b4_tokens)[
 297     };
 298     /// Token type.
 299     typedef token::yytokentype token_type;
 300
 301     /// Build a parser object.
 302     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 303     virtual ~]b4_parser_class_name[ ();
 304
 305     /// Parse.
 306     /// \returns  0 iff parsing succeeded.
 307     virtual int parse ();
 308
 309     /// The current debugging stream.
 310     std::ostream& debug_stream () const;
 311     /// Set the current debugging stream.
 312     void set_debug_stream (std::ostream &);
 313
 314     /// Type for debugging levels.
 315     typedef int debug_level_type;
 316     /// The current debugging level.
 317     debug_level_type debug_level () const;
 318     /// Set the current debugging level.
 319     void set_debug_level (debug_level_type l);
 320
 321   private:
 322
 323   public:
 324     /// Report a syntax error.
 325     /// \param loc    where the syntax error is found.
 326     /// \param msg    a description of the syntax error.
 327     virtual void error (const location_type& loc, const std::string& msg);
 328   private:
 329
 330 #if YYDEBUG
 331   public:
 332     /// \brief Report a symbol value on the debug stream.
 333     /// \param yytype       The token type.
 334     /// \param yyvaluep     Its semantic value.
 335     /// \param yylocationp  Its location.
 336     virtual void yy_symbol_value_print_ (int yytype,
 337                                          const semantic_type* yyvaluep,
 338                                          const location_type* yylocationp);
 339     /// \brief Report a symbol on the debug stream.
 340     /// \param yytype       The token type.
 341     /// \param yyvaluep     Its semantic value.
 342     /// \param yylocationp  Its location.
 343     virtual void yy_symbol_print_ (int yytype,
 344                                    const semantic_type* yyvaluep,
 345                                    const location_type* yylocationp);
 346   private:
 347     /* Debugging.  */
 348     int yydebug_;
 349     std::ostream* yycdebug_;
 350 #endif
 351
 352
 353     /// \brief Reclaim the memory associated to a symbol.
 354     /// \param yymsg        Why this token is reclaimed.
 355     /// \param yytype       The symbol type.
 356     /// \param yyvaluep     Its semantic value.
 357     /// \param yylocationp  Its location.
 358     inline void yydestruct_ (const char* yymsg,
 359                              int yytype,
 360                              semantic_type* yyvaluep,
 361                              location_type* yylocationp);
 362
 363 ]b4_parse_param_vars[
 364   };
 365
 366 ]dnl Redirections for glr.c.
 367 b4_percent_define_flag_if([[global_tokens_and_yystype]],
 368 [b4_token_defines(b4_tokens)])
 369 [
 370 #ifndef YYSTYPE
 371 # define YYSTYPE ]b4_namespace[::]b4_parser_class_name[::semantic_type
 372 #endif
 373 #ifndef YYLTYPE
 374 # define YYLTYPE ]b4_namespace[::]b4_parser_class_name[::location_type
 375 #endif
 376
 377 }
 378
 379 ]b4_percent_code_get([[provides]])[]dnl
 380
 381 [#endif /* ! defined PARSER_HEADER_H */]
 382 m4_divert_pop(0)