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 2 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, write to the Free Software
  19 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  20 # 02110-1301  USA
  21
  22
  23 # This skeleton produces a C++ class that encapsulates a C glr parser.
  24 # This is in order to reduce the maintenance burden.  The glr.c
  25 # skeleton is clean and pure enough so that there are no real
  26 # problems.  The C++ interface is the same as that of lalr1.cc.  In
  27 # fact, glr.c can replace yacc.c without the user noticing any
  28 # difference, and similarly for glr.cc replacing lalr1.cc.
  29 #
  30 # The passing of parse-params
  31 #
  32 #   The additional arguments are stored as members of the parser
  33 #   object, yyparser.  The C routines need to carry yyparser
  34 #   throughout the C parser; that easy: just let yyparser become an
  35 #   additional parse-param.  But because the C++ skeleton needs to
  36 #   know the "real" original parse-param, we save them
  37 #   (b4_parse_param_orig).  Note that b4_parse_param is overquoted
  38 #   (and c.m4 strips one level of quotes).  This is a PITA, and
  39 #   explains why there are so many levels of quotes.
  40 #
  41 # The locations
  42 #
  43 #   We use location.cc just like lalr1.cc, but because glr.c stores
  44 #   the locations in a (C++) union, the position and location classes
  45 #   must not have a constructor.  Therefore, contrary to lalr1.cc, we
  46 #   must not define "b4_location_constructors".  As a consequence the
  47 #   user must initialize the first positions (in particular the
  48 #   filename member).
  49
  50 # We require a pure interface using locations.
  51 m4_define([b4_locations_flag], [1])
  52 m4_define([b4_pure_flag],      [1])
  53
  54 # The header is mandatory.
  55 b4_defines_if([],
  56               [b4_fatal([b4_skeleton[: using %%defines is mandatory]])])
  57
  58 m4_include(b4_pkgdatadir/[c++.m4])
  59 m4_include(b4_pkgdatadir/[location.cc])
  60
  61 m4_define([b4_parser_class_name],
  62           [b4_percent_define_get([[parser_class_name]])])
  63 m4_define([b4_namespace],
  64           [b4_percent_define_get([[namespace]])])
  65
  66 # Save the parse parameters.
  67 m4_define([b4_parse_param_orig], m4_defn([b4_parse_param]))
  68
  69
  70 # b4_yy_symbol_print_generate
  71 # ---------------------------
  72 # Bypass the default implementation to generate the "yy_symbol_print"
  73 # and "yy_symbol_value_print" functions.
  74 m4_define([b4_yy_symbol_print_generate],
  75 [[
  76 /*--------------------.
  77 | Print this symbol.  |
  78 `--------------------*/
  79
  80 ]b4_c_ansi_function_def([yy_symbol_print],
  81     [static void],
  82     [[FILE *],               []],
  83     [[int yytype],           [yytype]],
  84     [[const b4_namespace::b4_parser_class_name::semantic_type *yyvaluep],
  85                              [yyvaluep]],
  86     [[const b4_namespace::b4_parser_class_name::location_type *yylocationp],
  87                              [yylocationp]],
  88     b4_parse_param)[
  89 {
  90 ]b4_parse_param_use[]dnl
  91 [  yyparser.yy_symbol_print_ (yytype, yyvaluep]b4_locations_if([, yylocationp])[);
  92 }
  93 ]])
  94
  95
  96 # Declare yyerror.
  97 m4_append([b4_post_prologue],
  98 [b4_syncline([@oline@], [@ofile@])
  99
 100 b4_c_ansi_function_decl([yyerror],
 101     [static void],
 102     [[b4_namespace::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 103     b4_parse_param,
 104     [[const char* msg], [msg]])])
 105
 106
 107 # Define yyerror.
 108 m4_append([b4_epilogue],
 109 [b4_syncline([@oline@], [@ofile@])[
 110 /*------------------.
 111 | Report an error.  |
 112 `------------------*/
 113
 114 ]b4_c_ansi_function_def([yyerror],
 115     [static void],
 116     [[b4_namespace::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 117     b4_parse_param,
 118     [[const char* msg], [msg]])[
 119 {
 120 ]b4_parse_param_use[]dnl
 121 [  yyparser.error (*yylocationp, msg);
 122 }
 123
 124
 125 namespace ]b4_namespace[
 126 {
 127 ]dnl In this section, the parse param are the original parse_params.
 128 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
 129 [  /// Build a parser object.
 130   ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [
 131     :])[
 132 #if YYDEBUG
 133     ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
 134       yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 135 #endif]b4_parse_param_cons[
 136   {
 137   }
 138
 139   ]b4_parser_class_name::~b4_parser_class_name[ ()
 140   {
 141   }
 142
 143   int
 144   ]b4_parser_class_name[::parse ()
 145   {
 146     return ::yyparse (*this]b4_user_args[);
 147   }
 148
 149 #if YYDEBUG
 150   /*--------------------.
 151   | Print this symbol.  |
 152   `--------------------*/
 153
 154   inline void
 155   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 156                            const semantic_type* yyvaluep, const location_type* yylocationp)
 157   {
 158     /* Pacify ``unused variable'' warnings.  */
 159     YYUSE (yyvaluep);
 160     YYUSE (yylocationp);
 161     switch (yytype)
 162       {
 163   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
 164 [        default:
 165           break;
 166       }
 167   }
 168
 169
 170   void
 171   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 172                            const semantic_type* yyvaluep, const location_type* yylocationp)
 173   {
 174     *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
 175                << ' ' << yytname[yytype] << " ("
 176                << *yylocationp << ": ";
 177     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
 178     *yycdebug_ << ')';
 179   }
 180
 181   std::ostream&
 182   ]b4_parser_class_name[::debug_stream () const
 183   {
 184     return *yycdebug_;
 185   }
 186
 187   void
 188   ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
 189   {
 190     yycdebug_ = &o;
 191   }
 192
 193
 194   ]b4_parser_class_name[::debug_level_type
 195   ]b4_parser_class_name[::debug_level () const
 196   {
 197     return yydebug_;
 198   }
 199
 200   void
 201   ]b4_parser_class_name[::set_debug_level (debug_level_type l)
 202   {
 203     yydebug_ = l;
 204   }
 205
 206 #endif
 207 ]m4_popdef([b4_parse_param])dnl
 208 [} // namespace ]b4_namespace[
 209
 210 ]])
 211
 212
 213 # Let glr.c believe that the user arguments include the parser itself.
 214 m4_ifset([b4_parse_param],
 215 [m4_pushdef([b4_parse_param],
 216             m4_dquote([[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]],]
 217 m4_defn([b4_parse_param])))],
 218 [m4_pushdef([b4_parse_param],
 219             [[[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]]]])
 220 ])
 221 m4_include(b4_pkgdatadir/[glr.c])
 222 m4_popdef([b4_parse_param])
 223
 224 m4_divert_push(0)
 225 @output(b4_spec_defines_file@)
 226 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 227   [2002, 2003, 2004, 2005, 2006])[
 228
 229 /* C++ GLR parser skeleton written by Akim Demaille.  */
 230
 231 #ifndef PARSER_HEADER_H
 232 # define PARSER_HEADER_H
 233
 234 ]b4_percent_code_get([[requires]])[
 235
 236 #include <string>
 237 #include <iostream>
 238
 239 /* Using locations.  */
 240 #define YYLSP_NEEDED ]b4_locations_flag[
 241
 242 namespace ]b4_namespace[
 243 {
 244   class position;
 245   class location;
 246 }
 247
 248 #include "location.hh"
 249
 250 /* Enabling traces.  */
 251 #ifndef YYDEBUG
 252 # define YYDEBUG ]b4_debug_flag[
 253 #endif
 254
 255 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 256    If N is 0, then set CURRENT to the empty location which ends
 257    the previous symbol: RHS[0] (always defined).  */
 258
 259 #ifndef YYLLOC_DEFAULT
 260 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 261     do                                                                  \
 262       if (N)                                                            \
 263         {                                                               \
 264           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 265           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 266         }                                                               \
 267       else                                                              \
 268         {                                                               \
 269           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 270         }                                                               \
 271     while (/*CONSTCOND*/ 0)
 272 #endif
 273
 274 namespace ]b4_namespace[
 275 {
 276   /// A Bison parser.
 277   class ]b4_parser_class_name[
 278   {
 279   public:
 280     /// Symbol semantic values.
 281 #ifndef YYSTYPE
 282 ]m4_ifdef([b4_stype],
 283 [    union semantic_type
 284     {
 285 b4_user_stype
 286     };],
 287 [m4_if(b4_tag_seen_flag, 0,
 288 [[    typedef int semantic_type;]],
 289 [[    typedef YYSTYPE semantic_type;]])])[
 290 #else
 291     typedef YYSTYPE semantic_type;
 292 #endif
 293     /// Symbol locations.
 294     typedef ]b4_percent_define_get([[location_type]])[ location_type;
 295     /// Tokens.
 296     struct token
 297     {
 298       ]b4_token_enums(b4_tokens)[
 299     };
 300     /// Token type.
 301     typedef token::yytokentype token_type;
 302
 303     /// Build a parser object.
 304     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 305     virtual ~]b4_parser_class_name[ ();
 306
 307     /// Parse.
 308     /// \returns  0 iff parsing succeeded.
 309     virtual int parse ();
 310
 311     /// The current debugging stream.
 312     std::ostream& debug_stream () const;
 313     /// Set the current debugging stream.
 314     void set_debug_stream (std::ostream &);
 315
 316     /// Type for debugging levels.
 317     typedef int debug_level_type;
 318     /// The current debugging level.
 319     debug_level_type debug_level () const;
 320     /// Set the current debugging level.
 321     void set_debug_level (debug_level_type l);
 322
 323   private:
 324
 325   public:
 326     /// Report a syntax error.
 327     /// \param loc    where the syntax error is found.
 328     /// \param msg    a description of the syntax error.
 329     virtual void error (const location_type& loc, const std::string& msg);
 330   private:
 331
 332 #if YYDEBUG
 333   public:
 334     /// \brief Report a symbol value on the debug stream.
 335     /// \param yytype       The token type.
 336     /// \param yyvaluep     Its semantic value.
 337     /// \param yylocationp  Its location.
 338     virtual void yy_symbol_value_print_ (int yytype,
 339                                          const semantic_type* yyvaluep,
 340                                          const location_type* yylocationp);
 341     /// \brief Report a symbol on the debug stream.
 342     /// \param yytype       The token type.
 343     /// \param yyvaluep     Its semantic value.
 344     /// \param yylocationp  Its location.
 345     virtual void yy_symbol_print_ (int yytype,
 346                                    const semantic_type* yyvaluep,
 347                                    const location_type* yylocationp);
 348   private:
 349     /* Debugging.  */
 350     int yydebug_;
 351     std::ostream* yycdebug_;
 352 #endif
 353
 354
 355     /// \brief Reclaim the memory associated to a symbol.
 356     /// \param yymsg        Why this token is reclaimed.
 357     /// \param yytype       The symbol type.
 358     /// \param yyvaluep     Its semantic value.
 359     /// \param yylocationp  Its location.
 360     inline void yydestruct_ (const char* yymsg,
 361                              int yytype,
 362                              semantic_type* yyvaluep,
 363                              location_type* yylocationp);
 364
 365 ]b4_parse_param_vars[
 366   };
 367
 368 ]dnl Redirections for glr.c.
 369 b4_percent_define_flag_if([[global_tokens_and_yystype]],
 370 [b4_token_defines(b4_tokens)])
 371 [
 372 #ifndef YYSTYPE
 373 # define YYSTYPE ]b4_namespace[::]b4_parser_class_name[::semantic_type
 374 #endif
 375 #ifndef YYLTYPE
 376 # define YYLTYPE ]b4_namespace[::]b4_parser_class_name[::location_type
 377 #endif
 378
 379 }
 380
 381 ]b4_percent_code_get([[provides]])[]dnl
 382
 383 [#endif /* ! defined PARSER_HEADER_H */]
 384 m4_divert_pop(0)