data/glr.cc

   1 m4_divert(-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               [m4_fatal(b4_skeleton[: using %defines is mandatory])])
  56
  57 m4_include(b4_pkgdatadir/[c++.m4])
  58 m4_include(b4_pkgdatadir/[location.cc])
  59
  60
  61 # Save the parse parameters.
  62 m4_define([b4_parse_param_orig], m4_defn([b4_parse_param]))
  63
  64
  65 # b4_yy_symbol_print_generate
  66 # ---------------------------
  67 # Bypass the default implementation to generate the "yy_symbol_print"
  68 # and "yy_symbol_value_print" functions.
  69 m4_define([b4_yy_symbol_print_generate],
  70 [[
  71 /*--------------------.
  72 | Print this symbol.  |
  73 `--------------------*/
  74
  75 ]b4_c_ansi_function_def([yy_symbol_print],
  76     [static void],
  77     [[FILE *],               []],
  78     [[int yytype],           [yytype]],
  79     [[const b4_namespace::b4_parser_class_name::semantic_type *yyvaluep],
  80                              [yyvaluep]],
  81     [[const b4_namespace::b4_parser_class_name::location_type *yylocationp],
  82                              [yylocationp]],
  83     b4_parse_param)[
  84 {
  85 ]b4_parse_param_use[]dnl
  86 [  yyparser.yy_symbol_print_ (yytype, yyvaluep]b4_locations_if([, yylocationp])[);
  87 }
  88 ]])
  89
  90
  91 # Declare yyerror.
  92 m4_append([b4_post_prologue],
  93 [/* Line __line__ of glr.cc.  */
  94 b4_syncline([@oline@], [@ofile@])
  95
  96 b4_c_ansi_function_decl([yyerror],
  97     [static void],
  98     [[b4_namespace::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
  99     b4_parse_param,
 100     [[const char* msg], [msg]])])
 101
 102
 103 # Define yyerror.
 104 m4_append([b4_epilogue],
 105 [/* Line __line__ of glr.cc.  */
 106 b4_syncline([@oline@], [@ofile@])[
 107 /*------------------.
 108 | Report an error.  |
 109 `------------------*/
 110
 111 ]b4_c_ansi_function_def([yyerror],
 112     [static void],
 113     [[b4_namespace::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 114     b4_parse_param,
 115     [[const char* msg], [msg]])[
 116 {
 117 ]b4_parse_param_use[]dnl
 118 [  yyparser.error (*yylocationp, msg);
 119 }
 120
 121
 122 namespace ]b4_namespace[
 123 {
 124 ]dnl In this section, the parse param are the original parse_params.
 125 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
 126 [  /// Build a parser object.
 127   ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)
 128     : yycdebug_ (&std::cerr)]b4_parse_param_cons[
 129   {
 130   }
 131
 132   ]b4_parser_class_name::~b4_parser_class_name[ ()
 133   {
 134   }
 135
 136   int
 137   ]b4_parser_class_name[::parse ()
 138   {
 139     return ::yyparse (*this]b4_user_args[);
 140   }
 141
 142 #if YYDEBUG
 143   /*--------------------.
 144   | Print this symbol.  |
 145   `--------------------*/
 146
 147   inline void
 148   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 149                            const semantic_type* yyvaluep, const location_type* yylocationp)
 150   {
 151     /* Pacify ``unused variable'' warnings.  */
 152     YYUSE (yyvaluep);
 153     YYUSE (yylocationp);
 154     switch (yytype)
 155       {
 156   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
 157 [        default:
 158           break;
 159       }
 160   }
 161
 162
 163   void
 164   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 165                            const semantic_type* yyvaluep, const location_type* yylocationp)
 166   {
 167     *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
 168                << ' ' << yytname[yytype] << " ("
 169                << *yylocationp << ": ";
 170     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
 171     *yycdebug_ << ')';
 172   }
 173
 174   std::ostream&
 175   ]b4_parser_class_name[::debug_stream () const
 176   {
 177     return *yycdebug_;
 178   }
 179
 180   void
 181   ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
 182   {
 183     yycdebug_ = &o;
 184   }
 185
 186
 187   ]b4_parser_class_name[::debug_level_type
 188   ]b4_parser_class_name[::debug_level () const
 189   {
 190     return ::yydebug;
 191   }
 192
 193   void
 194   ]b4_parser_class_name[::set_debug_level (debug_level_type l)
 195   {
 196     ::yydebug = l;
 197   }
 198
 199 #endif /* ! YYDEBUG */
 200 ]m4_popdef([b4_parse_param])dnl
 201 [} // namespace ]b4_namespace[
 202
 203 ]])
 204
 205
 206 # Let glr.c believe that the user arguments include the parser itself.
 207 m4_ifset([b4_parse_param],
 208 [m4_pushdef([b4_parse_param],
 209             m4_dquote([[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]],]
 210 m4_defn([b4_parse_param])))],
 211 [m4_pushdef([b4_parse_param],
 212             [[[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]]]])
 213 ])
 214 m4_include(b4_pkgdatadir/[glr.c])
 215 m4_popdef([b4_parse_param])
 216
 217 @output @output_header_name@
 218 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 219   [2002, 2003, 2004, 2005, 2006])[
 220
 221 /* C++ GLR parser skeleton written by Akim Demaille.  */
 222
 223 #ifndef PARSER_HEADER_H
 224 # define PARSER_HEADER_H
 225
 226 #include <string>
 227 #include <iostream>
 228
 229 /* Using locations.  */
 230 #define YYLSP_NEEDED ]b4_locations_flag[
 231
 232 namespace ]b4_namespace[
 233 {
 234   class position;
 235   class location;
 236 }
 237
 238 ]m4_ifdef([b4_start_header],
 239 [[/* Copy the %start-header blocks.  */
 240 ]b4_start_header])[]dnl
 241
 242 [/* Line __line__ of glr.cc.  */
 243 ]b4_syncline([@oline@], [@ofile@])[
 244
 245 #include "location.hh"
 246
 247 /* Enabling traces.  */
 248 #ifndef YYDEBUG
 249 # define YYDEBUG ]b4_debug_flag[
 250 #endif
 251
 252 /* Enabling verbose error messages.  */
 253 #ifdef YYERROR_VERBOSE
 254 # undef YYERROR_VERBOSE
 255 # define YYERROR_VERBOSE 1
 256 #else
 257 # define YYERROR_VERBOSE ]b4_error_verbose_flag[
 258 #endif
 259
 260 /* Enabling the token table.  */
 261 #ifndef YYTOKEN_TABLE
 262 # define YYTOKEN_TABLE ]b4_token_table[
 263 #endif
 264
 265 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 266    If N is 0, then set CURRENT to the empty location which ends
 267    the previous symbol: RHS[0] (always defined).  */
 268
 269 #ifndef YYLLOC_DEFAULT
 270 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 271     do                                                                  \
 272       if (N)                                                            \
 273         {                                                               \
 274           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 275           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 276         }                                                               \
 277       else                                                              \
 278         {                                                               \
 279           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 280         }                                                               \
 281     while (/*CONSTCOND*/ 0)
 282 #endif
 283
 284 namespace ]b4_namespace[
 285 {
 286   /// A Bison parser.
 287   class ]b4_parser_class_name[
 288   {
 289   public:
 290     /// Symbol semantic values.
 291 #ifndef YYSTYPE
 292 ]m4_ifdef([b4_stype],
 293 [    union semantic_type
 294 b4_stype
 295 /* Line __line__ of lalr1.cc.  */
 296 b4_syncline([@oline@], [@ofile@])
 297         ;],
 298 [    typedef int semantic_type;])[
 299 #else
 300     typedef YYSTYPE semantic_type;
 301 #endif
 302     /// Symbol locations.
 303     typedef ]b4_location_type[ location_type;
 304     /// Tokens.
 305     struct token
 306     {
 307       ]b4_token_enums(b4_tokens)[
 308     };
 309     /// Token type.
 310     typedef token::yytokentype token_type;
 311
 312     /// Build a parser object.
 313     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 314     virtual ~]b4_parser_class_name[ ();
 315
 316     /// Parse.
 317     /// \returns  0 iff parsing succeeded.
 318     virtual int parse ();
 319
 320     /// The current debugging stream.
 321     std::ostream& debug_stream () const;
 322     /// Set the current debugging stream.
 323     void set_debug_stream (std::ostream &);
 324
 325     /// Type for debugging levels.
 326     typedef int debug_level_type;
 327     /// The current debugging level.
 328     debug_level_type debug_level () const;
 329     /// Set the current debugging level.
 330     void set_debug_level (debug_level_type l);
 331
 332   private:
 333
 334   public:
 335     /// Report a syntax error.
 336     /// \param loc    where the syntax error is found.
 337     /// \param msg    a description of the syntax error.
 338     virtual void error (const location_type& loc, const std::string& msg);
 339   private:
 340
 341 #if YYDEBUG
 342   public:
 343     /// \brief Report a symbol value 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_value_print_ (int yytype,
 348                                          const semantic_type* yyvaluep,
 349                                          const location_type* yylocationp);
 350     /// \brief Report a symbol on the debug stream.
 351     /// \param yytype       The token type.
 352     /// \param yyvaluep     Its semantic value.
 353     /// \param yylocationp  Its location.
 354     virtual void yy_symbol_print_ (int yytype,
 355                                    const semantic_type* yyvaluep,
 356                                    const location_type* yylocationp);
 357   private:
 358 #endif /* ! YYDEBUG */
 359
 360
 361     /// \brief Reclaim the memory associated to a symbol.
 362     /// \param yymsg        Why this token is reclaimed.
 363     /// \param yytype       The symbol type.
 364     /// \param yyvaluep     Its semantic value.
 365     /// \param yylocationp  Its location.
 366     inline void yydestruct_ (const char* yymsg,
 367                              int yytype,
 368                              semantic_type* yyvaluep,
 369                              location_type* yylocationp);
 370
 371     /* Debugging.  */
 372     std::ostream* yycdebug_;
 373 ]b4_parse_param_vars[
 374   };
 375
 376 ]dnl Redirections for glr.c.
 377 m4_ifset([b4_global_tokens_and_yystype],
 378 [b4_token_defines(b4_tokens)])
 379 [
 380 #ifndef YYSTYPE
 381 # define YYSTYPE ]b4_namespace[::]b4_parser_class_name[::semantic_type
 382 #endif
 383 #ifndef YYLTYPE
 384 # define YYLTYPE ]b4_namespace[::]b4_parser_class_name[::location_type
 385 #endif
 386
 387 }
 388
 389 ]m4_ifdef([b4_end_header],
 390 [[/* Copy the %end-header blocks.  */
 391 ]b4_end_header])[]dnl
 392
 393 [#endif /* ! defined PARSER_HEADER_H */]