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 m4_define([b4_parser_class_name],
  61           [b4_get_percent_define([[parser_class_name]])])
  62 m4_define([b4_namespace],
  63           [b4_get_percent_define([[namespace]])])
  64
  65 # Save the parse parameters.
  66 m4_define([b4_parse_param_orig], m4_defn([b4_parse_param]))
  67
  68
  69 # b4_yy_symbol_print_generate
  70 # ---------------------------
  71 # Bypass the default implementation to generate the "yy_symbol_print"
  72 # and "yy_symbol_value_print" functions.
  73 m4_define([b4_yy_symbol_print_generate],
  74 [[
  75 /*--------------------.
  76 | Print this symbol.  |
  77 `--------------------*/
  78
  79 ]b4_c_ansi_function_def([yy_symbol_print],
  80     [static void],
  81     [[FILE *],               []],
  82     [[int yytype],           [yytype]],
  83     [[const b4_namespace::b4_parser_class_name::semantic_type *yyvaluep],
  84                              [yyvaluep]],
  85     [[const b4_namespace::b4_parser_class_name::location_type *yylocationp],
  86                              [yylocationp]],
  87     b4_parse_param)[
  88 {
  89 ]b4_parse_param_use[]dnl
  90 [  yyparser.yy_symbol_print_ (yytype, yyvaluep]b4_locations_if([, yylocationp])[);
  91 }
  92 ]])
  93
  94
  95 # Declare yyerror.
  96 m4_append([b4_post_prologue],
  97 [b4_syncline([@oline@], [@ofile@])
  98
  99 b4_c_ansi_function_decl([yyerror],
 100     [static void],
 101     [[b4_namespace::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 102     b4_parse_param,
 103     [[const char* msg], [msg]])])
 104
 105
 106 # Define yyerror.
 107 m4_append([b4_epilogue],
 108 [b4_syncline([@oline@], [@ofile@])[
 109 /*------------------.
 110 | Report an error.  |
 111 `------------------*/
 112
 113 ]b4_c_ansi_function_def([yyerror],
 114     [static void],
 115     [[b4_namespace::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 116     b4_parse_param,
 117     [[const char* msg], [msg]])[
 118 {
 119 ]b4_parse_param_use[]dnl
 120 [  yyparser.error (*yylocationp, msg);
 121 }
 122
 123
 124 namespace ]b4_namespace[
 125 {
 126 ]dnl In this section, the parse param are the original parse_params.
 127 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
 128 [  /// Build a parser object.
 129   ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [
 130     :])[
 131 #if YYDEBUG
 132     ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
 133       yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 134 #endif]b4_parse_param_cons[
 135   {
 136   }
 137
 138   ]b4_parser_class_name::~b4_parser_class_name[ ()
 139   {
 140   }
 141
 142   int
 143   ]b4_parser_class_name[::parse ()
 144   {
 145     return ::yyparse (*this]b4_user_args[);
 146   }
 147
 148 #if YYDEBUG
 149   /*--------------------.
 150   | Print this symbol.  |
 151   `--------------------*/
 152
 153   inline void
 154   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 155                            const semantic_type* yyvaluep, const location_type* yylocationp)
 156   {
 157     /* Pacify ``unused variable'' warnings.  */
 158     YYUSE (yyvaluep);
 159     YYUSE (yylocationp);
 160     switch (yytype)
 161       {
 162   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
 163 [        default:
 164           break;
 165       }
 166   }
 167
 168
 169   void
 170   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 171                            const semantic_type* yyvaluep, const location_type* yylocationp)
 172   {
 173     *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
 174                << ' ' << yytname[yytype] << " ("
 175                << *yylocationp << ": ";
 176     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
 177     *yycdebug_ << ')';
 178   }
 179
 180   std::ostream&
 181   ]b4_parser_class_name[::debug_stream () const
 182   {
 183     return *yycdebug_;
 184   }
 185
 186   void
 187   ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
 188   {
 189     yycdebug_ = &o;
 190   }
 191
 192
 193   ]b4_parser_class_name[::debug_level_type
 194   ]b4_parser_class_name[::debug_level () const
 195   {
 196     return yydebug_;
 197   }
 198
 199   void
 200   ]b4_parser_class_name[::set_debug_level (debug_level_type l)
 201   {
 202     yydebug_ = l;
 203   }
 204
 205 #endif
 206 ]m4_popdef([b4_parse_param])dnl
 207 [} // namespace ]b4_namespace[
 208
 209 ]])
 210
 211
 212 # Let glr.c believe that the user arguments include the parser itself.
 213 m4_ifset([b4_parse_param],
 214 [m4_pushdef([b4_parse_param],
 215             m4_dquote([[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]],]
 216 m4_defn([b4_parse_param])))],
 217 [m4_pushdef([b4_parse_param],
 218             [[[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]]]])
 219 ])
 220 m4_include(b4_pkgdatadir/[glr.c])
 221 m4_popdef([b4_parse_param])
 222
 223 m4_divert_push(0)
 224 @output(b4_spec_defines_file@)
 225 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 226   [2002, 2003, 2004, 2005, 2006])[
 227
 228 /* C++ GLR parser skeleton written by Akim Demaille.  */
 229
 230 #ifndef PARSER_HEADER_H
 231 # define PARSER_HEADER_H
 232
 233 ]b4_get_percent_code([[requires]])[
 234
 235 #include <string>
 236 #include <iostream>
 237
 238 /* Using locations.  */
 239 #define YYLSP_NEEDED ]b4_locations_flag[
 240
 241 namespace ]b4_namespace[
 242 {
 243   class position;
 244   class location;
 245 }
 246
 247 #include "location.hh"
 248
 249 /* Enabling traces.  */
 250 #ifndef YYDEBUG
 251 # define YYDEBUG ]b4_debug_flag[
 252 #endif
 253
 254 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 255    If N is 0, then set CURRENT to the empty location which ends
 256    the previous symbol: RHS[0] (always defined).  */
 257
 258 #ifndef YYLLOC_DEFAULT
 259 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 260     do                                                                  \
 261       if (N)                                                            \
 262         {                                                               \
 263           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 264           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 265         }                                                               \
 266       else                                                              \
 267         {                                                               \
 268           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 269         }                                                               \
 270     while (/*CONSTCOND*/ 0)
 271 #endif
 272
 273 namespace ]b4_namespace[
 274 {
 275   /// A Bison parser.
 276   class ]b4_parser_class_name[
 277   {
 278   public:
 279     /// Symbol semantic values.
 280 #ifndef YYSTYPE
 281 ]m4_ifdef([b4_stype],
 282 [    union semantic_type
 283     {
 284 b4_user_stype
 285     };],
 286 [m4_if(b4_tag_seen_flag, 0,
 287 [[    typedef int semantic_type;]],
 288 [[    typedef YYSTYPE semantic_type;]])])[
 289 #else
 290     typedef YYSTYPE semantic_type;
 291 #endif
 292     /// Symbol locations.
 293     typedef ]b4_get_percent_define([[location_type]])[ location_type;
 294     /// Tokens.
 295     struct token
 296     {
 297       ]b4_token_enums(b4_tokens)[
 298     };
 299     /// Token type.
 300     typedef token::yytokentype token_type;
 301
 302     /// Build a parser object.
 303     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 304     virtual ~]b4_parser_class_name[ ();
 305
 306     /// Parse.
 307     /// \returns  0 iff parsing succeeded.
 308     virtual int parse ();
 309
 310     /// The current debugging stream.
 311     std::ostream& debug_stream () const;
 312     /// Set the current debugging stream.
 313     void set_debug_stream (std::ostream &);
 314
 315     /// Type for debugging levels.
 316     typedef int debug_level_type;
 317     /// The current debugging level.
 318     debug_level_type debug_level () const;
 319     /// Set the current debugging level.
 320     void set_debug_level (debug_level_type l);
 321
 322   private:
 323
 324   public:
 325     /// Report a syntax error.
 326     /// \param loc    where the syntax error is found.
 327     /// \param msg    a description of the syntax error.
 328     virtual void error (const location_type& loc, const std::string& msg);
 329   private:
 330
 331 #if YYDEBUG
 332   public:
 333     /// \brief Report a symbol value on the debug stream.
 334     /// \param yytype       The token type.
 335     /// \param yyvaluep     Its semantic value.
 336     /// \param yylocationp  Its location.
 337     virtual void yy_symbol_value_print_ (int yytype,
 338                                          const semantic_type* yyvaluep,
 339                                          const location_type* yylocationp);
 340     /// \brief Report a symbol on the debug stream.
 341     /// \param yytype       The token type.
 342     /// \param yyvaluep     Its semantic value.
 343     /// \param yylocationp  Its location.
 344     virtual void yy_symbol_print_ (int yytype,
 345                                    const semantic_type* yyvaluep,
 346                                    const location_type* yylocationp);
 347   private:
 348     /* Debugging.  */
 349     int yydebug_;
 350     std::ostream* yycdebug_;
 351 #endif
 352
 353
 354     /// \brief Reclaim the memory associated to a symbol.
 355     /// \param yymsg        Why this token is reclaimed.
 356     /// \param yytype       The symbol type.
 357     /// \param yyvaluep     Its semantic value.
 358     /// \param yylocationp  Its location.
 359     inline void yydestruct_ (const char* yymsg,
 360                              int yytype,
 361                              semantic_type* yyvaluep,
 362                              location_type* yylocationp);
 363
 364 ]b4_parse_param_vars[
 365   };
 366
 367 ]dnl Redirections for glr.c.
 368 m4_ifval(b4_get_percent_define([[global_tokens_and_yystype]]),
 369 [b4_token_defines(b4_tokens)])
 370 [
 371 #ifndef YYSTYPE
 372 # define YYSTYPE ]b4_namespace[::]b4_parser_class_name[::semantic_type
 373 #endif
 374 #ifndef YYLTYPE
 375 # define YYLTYPE ]b4_namespace[::]b4_parser_class_name[::location_type
 376 #endif
 377
 378 }
 379
 380 ]b4_get_percent_code([[provides]])[]dnl
 381
 382 [#endif /* ! defined PARSER_HEADER_H */]
 383 m4_divert_pop(0)