data/glr.cc

   1 # C++ GLR skeleton for Bison
   2 # Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation,
   3 # Inc.
   4
   5 # This program is free software: you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation, either version 3 of the License, or
   8 # (at your option) any later version.
   9 #
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License
  16 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17
  18
  19 # This skeleton produces a C++ class that encapsulates a C glr parser.
  20 # This is in order to reduce the maintenance burden.  The glr.c
  21 # skeleton is clean and pure enough so that there are no real
  22 # problems.  The C++ interface is the same as that of lalr1.cc.  In
  23 # fact, glr.c can replace yacc.c without the user noticing any
  24 # difference, and similarly for glr.cc replacing lalr1.cc.
  25 #
  26 # The passing of parse-params
  27 #
  28 #   The additional arguments are stored as members of the parser
  29 #   object, yyparser.  The C routines need to carry yyparser
  30 #   throughout the C parser; that's easy: make yyparser an
  31 #   additional parse-param.  But because the C++ skeleton needs to
  32 #   know the "real" original parse-param, we save them
  33 #   (b4_parse_param_orig).  Note that b4_parse_param is overquoted
  34 #   (and c.m4 strips one level of quotes).  This is a PITA, and
  35 #   explains why there are so many levels of quotes.
  36 #
  37 # The locations
  38 #
  39 #   We use location.cc just like lalr1.cc, but because glr.c stores
  40 #   the locations in a union, the position and location classes
  41 #   must not have a constructor.  Therefore, contrary to lalr1.cc, we
  42 #   must not define "b4_location_constructors".  As a consequence the
  43 #   user must initialize the first positions (in particular the
  44 #   filename member).
  45
  46 # We require a pure interface using locations.
  47 m4_define([b4_locations_flag], [1])
  48 m4_define([b4_pure_flag],      [1])
  49
  50 # The header is mandatory.
  51 b4_defines_if([],
  52               [b4_fatal([b4_skeleton[: using %%defines is mandatory]])])
  53
  54 m4_include(b4_pkgdatadir/[c++.m4])
  55 m4_include(b4_pkgdatadir/[location.cc])
  56
  57 m4_define([b4_parser_class_name],
  58           [b4_percent_define_get([[parser_class_name]])])
  59
  60 # Save the parse parameters.
  61 m4_define([b4_parse_param_orig], m4_defn([b4_parse_param]))
  62
  63
  64 # b4_yy_symbol_print_generate
  65 # ---------------------------
  66 # Bypass the default implementation to generate the "yy_symbol_print"
  67 # and "yy_symbol_value_print" functions.
  68 m4_define([b4_yy_symbol_print_generate],
  69 [[
  70 /*--------------------.
  71 | Print this symbol.  |
  72 `--------------------*/
  73
  74 ]b4_c_ansi_function_def([yy_symbol_print],
  75     [static void],
  76     [[FILE *],               []],
  77     [[int yytype],           [yytype]],
  78     [[const b4_namespace_ref::b4_parser_class_name::semantic_type *yyvaluep],
  79                              [yyvaluep]],
  80     [[const b4_namespace_ref::b4_parser_class_name::location_type *yylocationp],
  81                              [yylocationp]],
  82     b4_parse_param)[
  83 {
  84 ]b4_parse_param_use[]dnl
  85 [  yyparser.yy_symbol_print_ (yytype, yyvaluep]b4_locations_if([, yylocationp])[);
  86 }
  87 ]])
  88
  89
  90 # Declare yyerror.
  91 m4_append([b4_post_prologue],
  92 [b4_syncline([@oline@], [@ofile@])
  93
  94 b4_c_ansi_function_decl([yyerror],
  95     [static void],
  96     [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
  97     b4_parse_param,
  98     [[const char* msg], [msg]])])
  99
 100
 101 # Define yyerror.
 102 m4_append([b4_epilogue],
 103 [b4_syncline([@oline@], [@ofile@])[
 104 /*------------------.
 105 | Report an error.  |
 106 `------------------*/
 107
 108 ]b4_c_ansi_function_def([yyerror],
 109     [static void],
 110     [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 111     b4_parse_param,
 112     [[const char* msg], [msg]])[
 113 {
 114 ]b4_parse_param_use[]dnl
 115 [  yyparser.error (*yylocationp, msg);
 116 }
 117
 118
 119 ]b4_namespace_open[
 120 ]dnl In this section, the parse param are the original parse_params.
 121 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
 122 [  /// Build a parser object.
 123   ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [
 124     :])[
 125 #if YYDEBUG
 126     ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
 127       yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 128 #endif]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 ]b4_symbol_foreach([b4_symbol_printer])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
 200 ]m4_popdef([b4_parse_param])dnl
 201 b4_namespace_close[
 202 ]])
 203
 204
 205 # Let glr.c believe that the user arguments include the parser itself.
 206 m4_ifset([b4_parse_param],
 207 [m4_pushdef([b4_parse_param],
 208             m4_dquote([[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]],]
 209 m4_defn([b4_parse_param])))],
 210 [m4_pushdef([b4_parse_param],
 211             [[[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]]]])
 212 ])
 213 m4_include(b4_pkgdatadir/[glr.c])
 214 m4_popdef([b4_parse_param])
 215
 216 m4_divert_push(0)
 217 @output(b4_spec_defines_file@)@
 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 ]b4_percent_code_get([[requires]])[
 227
 228 #include <string>
 229 #include <iostream>
 230
 231 /* Using locations.  */
 232 #define YYLSP_NEEDED ]b4_locations_flag[
 233
 234 ]b4_namespace_open[
 235   class position;
 236   class location;
 237 ]b4_namespace_close[
 238
 239 #include "location.hh"
 240
 241 /* Enabling traces.  */
 242 #ifndef YYDEBUG
 243 # define YYDEBUG ]b4_debug_flag[
 244 #endif
 245
 246 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 247    If N is 0, then set CURRENT to the empty location which ends
 248    the previous symbol: RHS[0] (always defined).  */
 249
 250 #ifndef YYLLOC_DEFAULT
 251 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 252     do                                                                  \
 253       if (N)                                                            \
 254         {                                                               \
 255           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 256           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 257         }                                                               \
 258       else                                                              \
 259         {                                                               \
 260           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 261         }                                                               \
 262     while (/*CONSTCOND*/ 0)
 263 #endif
 264
 265 ]b4_namespace_open[
 266   /// A Bison parser.
 267   class ]b4_parser_class_name[
 268   {
 269   public:
 270     /// Symbol semantic values.
 271 #ifndef YYSTYPE
 272 ]m4_ifdef([b4_stype],
 273 [    union semantic_type
 274     {
 275 b4_user_stype
 276     };],
 277 [m4_if(b4_tag_seen_flag, 0,
 278 [[    typedef int semantic_type;]],
 279 [[    typedef YYSTYPE semantic_type;]])])[
 280 #else
 281     typedef YYSTYPE semantic_type;
 282 #endif
 283     /// Symbol locations.
 284     typedef ]b4_percent_define_get([[location_type]])[ location_type;
 285     /// Tokens.
 286     struct token
 287     {
 288       ]b4_token_enums(b4_tokens)[
 289     };
 290     /// Token type.
 291     typedef token::yytokentype token_type;
 292
 293     /// Build a parser object.
 294     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 295     virtual ~]b4_parser_class_name[ ();
 296
 297     /// Parse.
 298     /// \returns  0 iff parsing succeeded.
 299     virtual int parse ();
 300
 301     /// The current debugging stream.
 302     std::ostream& debug_stream () const;
 303     /// Set the current debugging stream.
 304     void set_debug_stream (std::ostream &);
 305
 306     /// Type for debugging levels.
 307     typedef int debug_level_type;
 308     /// The current debugging level.
 309     debug_level_type debug_level () const;
 310     /// Set the current debugging level.
 311     void set_debug_level (debug_level_type l);
 312
 313   public:
 314     /// Report a syntax error.
 315     /// \param loc    where the syntax error is found.
 316     /// \param msg    a description of the syntax error.
 317     virtual void error (const location_type& loc, const std::string& msg);
 318
 319 #if YYDEBUG
 320   public:
 321     /// \brief Report a symbol value on the debug stream.
 322     /// \param yytype       The token type.
 323     /// \param yyvaluep     Its semantic value.
 324     /// \param yylocationp  Its location.
 325     virtual void yy_symbol_value_print_ (int yytype,
 326                                          const semantic_type* yyvaluep,
 327                                          const location_type* yylocationp);
 328     /// \brief Report a symbol on the debug stream.
 329     /// \param yytype       The token type.
 330     /// \param yyvaluep     Its semantic value.
 331     /// \param yylocationp  Its location.
 332     virtual void yy_symbol_print_ (int yytype,
 333                                    const semantic_type* yyvaluep,
 334                                    const location_type* yylocationp);
 335   private:
 336     /* Debugging.  */
 337     int yydebug_;
 338     std::ostream* yycdebug_;
 339 #endif
 340
 341     /// \brief Reclaim the memory associated to a symbol.
 342     /// \param yymsg        Why this token is reclaimed.
 343     /// \param yytype       The symbol type.
 344     /// \param yyvaluep     Its semantic value.
 345     /// \param yylocationp  Its location.
 346     inline void yydestruct_ (const char* yymsg,
 347                              int yytype,
 348                              semantic_type* yyvaluep,
 349                              location_type* yylocationp);
 350
 351 ]b4_parse_param_vars[
 352   };
 353
 354 ]dnl Redirections for glr.c.
 355 b4_percent_define_flag_if([[global_tokens_and_yystype]],
 356 [b4_token_defines(b4_tokens)])
 357 [
 358 #ifndef YYSTYPE
 359 # define YYSTYPE ]b4_namespace_ref[::]b4_parser_class_name[::semantic_type
 360 #endif
 361 #ifndef YYLTYPE
 362 # define YYLTYPE ]b4_namespace_ref[::]b4_parser_class_name[::location_type
 363 #endif
 364
 365 ]b4_namespace_close[
 366
 367 ]b4_percent_code_get([[provides]])[]dnl
 368
 369 [#endif /* ! defined PARSER_HEADER_H */]
 370 m4_divert_pop(0)