data/glr.cc

   1                                                                     -*- C -*-
   2
   3 # C++ GLR skeleton for Bison
   4
   5 # Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
   6 # 2010 Free Software Foundation, Inc.
   7
   8 # This program is free software: you can redistribute it and/or modify
   9 # it under the terms of the GNU General Public License as published by
  10 # the Free Software Foundation, either version 3 of the License, or
  11 # (at your option) any later version.
  12 #
  13 # This program is distributed in the hope that it will be useful,
  14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 # GNU General Public License for more details.
  17 #
  18 # You should have received a copy of the GNU General Public License
  19 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  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 b4_percent_define_ifdef([[location_type]], [],
  59                         [m4_include(b4_pkgdatadir/[location.cc])])
  60
  61 m4_define([b4_parser_class_name],
  62           [b4_percent_define_get([[parser_class_name]])])
  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_ref::b4_parser_class_name::semantic_type *yyvaluep],
  83                              [yyvaluep]],
  84     [[const b4_namespace_ref::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_ref::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_ref::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 ]b4_namespace_open[
 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[)]m4_ifset([b4_parse_param], [
 128     :])[
 129 #if YYDEBUG
 130     ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
 131       yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 132 #endif]b4_parse_param_cons[
 133   {
 134   }
 135
 136   ]b4_parser_class_name::~b4_parser_class_name[ ()
 137   {
 138   }
 139
 140   int
 141   ]b4_parser_class_name[::parse ()
 142   {
 143     return ::yyparse (*this]b4_user_args[);
 144   }
 145
 146 #if YYDEBUG
 147   /*--------------------.
 148   | Print this symbol.  |
 149   `--------------------*/
 150
 151   inline void
 152   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 153                            const semantic_type* yyvaluep, const location_type* yylocationp)
 154   {
 155     /* Pacify ``unused variable'' warnings.  */
 156     YYUSE (yyvaluep);
 157     YYUSE (yylocationp);
 158     switch (yytype)
 159       {
 160   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
 161 [        default:
 162           break;
 163       }
 164   }
 165
 166
 167   void
 168   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 169                            const semantic_type* yyvaluep, const location_type* yylocationp)
 170   {
 171     *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
 172                << ' ' << yytname[yytype] << " ("
 173                << *yylocationp << ": ";
 174     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
 175     *yycdebug_ << ')';
 176   }
 177
 178   std::ostream&
 179   ]b4_parser_class_name[::debug_stream () const
 180   {
 181     return *yycdebug_;
 182   }
 183
 184   void
 185   ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
 186   {
 187     yycdebug_ = &o;
 188   }
 189
 190
 191   ]b4_parser_class_name[::debug_level_type
 192   ]b4_parser_class_name[::debug_level () const
 193   {
 194     return yydebug_;
 195   }
 196
 197   void
 198   ]b4_parser_class_name[::set_debug_level (debug_level_type l)
 199   {
 200     yydebug_ = l;
 201   }
 202
 203 #endif
 204 ]m4_popdef([b4_parse_param])dnl
 205 b4_namespace_close[
 206
 207 ]])
 208
 209
 210 # Let glr.c believe that the user arguments include the parser itself.
 211 m4_ifset([b4_parse_param],
 212 [m4_pushdef([b4_parse_param],
 213             m4_dquote([[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]],]
 214 m4_defn([b4_parse_param])))],
 215 [m4_pushdef([b4_parse_param],
 216             [[[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]]]])
 217 ])
 218 m4_include(b4_pkgdatadir/[glr.c])
 219 m4_popdef([b4_parse_param])
 220
 221 m4_divert_push(0)
 222 @output(b4_spec_defines_file@)@
 223 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 224              [2002, 2003, 2004, 2005, 2006, 2009, 2010])[
 225
 226 /* C++ GLR parser skeleton written by Akim Demaille.  */
 227
 228 #ifndef PARSER_HEADER_H
 229 # define PARSER_HEADER_H
 230
 231 ]b4_percent_code_get([[requires]])[
 232
 233 #include <string>
 234 #include <iostream>
 235 ]b4_percent_define_ifdef([[location_type]], [],
 236                          [[#include "location.hh"]])[
 237
 238 /* Using locations.  */
 239 #define YYLSP_NEEDED ]b4_locations_flag[
 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]],
 285                                    [[location]])[ location_type;
 286     /// Tokens.
 287     struct token
 288     {
 289       ]b4_token_enums(b4_tokens)[
 290     };
 291     /// Token type.
 292     typedef token::yytokentype token_type;
 293
 294     /// Build a parser object.
 295     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 296     virtual ~]b4_parser_class_name[ ();
 297
 298     /// Parse.
 299     /// \returns  0 iff parsing succeeded.
 300     virtual int parse ();
 301
 302     /// The current debugging stream.
 303     std::ostream& debug_stream () const;
 304     /// Set the current debugging stream.
 305     void set_debug_stream (std::ostream &);
 306
 307     /// Type for debugging levels.
 308     typedef int debug_level_type;
 309     /// The current debugging level.
 310     debug_level_type debug_level () const;
 311     /// Set the current debugging level.
 312     void set_debug_level (debug_level_type l);
 313
 314   private:
 315
 316   public:
 317     /// Report a syntax error.
 318     /// \param loc    where the syntax error is found.
 319     /// \param msg    a description of the syntax error.
 320     virtual void error (const location_type& loc, const std::string& msg);
 321   private:
 322
 323 #if YYDEBUG
 324   public:
 325     /// \brief Report a symbol value on the debug stream.
 326     /// \param yytype       The token type.
 327     /// \param yyvaluep     Its semantic value.
 328     /// \param yylocationp  Its location.
 329     virtual void yy_symbol_value_print_ (int yytype,
 330                                          const semantic_type* yyvaluep,
 331                                          const location_type* yylocationp);
 332     /// \brief Report a symbol 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_print_ (int yytype,
 337                                    const semantic_type* yyvaluep,
 338                                    const location_type* yylocationp);
 339   private:
 340     /* Debugging.  */
 341     int yydebug_;
 342     std::ostream* yycdebug_;
 343 #endif
 344
 345
 346     /// \brief Reclaim the memory associated to a symbol.
 347     /// \param yymsg        Why this token is reclaimed.
 348     /// \param yytype       The symbol type.
 349     /// \param yyvaluep     Its semantic value.
 350     /// \param yylocationp  Its location.
 351     inline void yydestruct_ (const char* yymsg,
 352                              int yytype,
 353                              semantic_type* yyvaluep,
 354                              location_type* yylocationp);
 355
 356 ]b4_parse_param_vars[
 357   };
 358
 359 ]dnl Redirections for glr.c.
 360 b4_percent_define_flag_if([[global_tokens_and_yystype]],
 361 [b4_token_defines(b4_tokens)])
 362 [
 363 #ifndef YYSTYPE
 364 # define YYSTYPE ]b4_namespace_ref[::]b4_parser_class_name[::semantic_type
 365 #endif
 366 #ifndef YYLTYPE
 367 # define YYLTYPE ]b4_namespace_ref[::]b4_parser_class_name[::location_type
 368 #endif
 369
 370 ]b4_namespace_close[
 371
 372 ]b4_percent_code_get([[provides]])[]dnl
 373
 374 [#endif /* ! defined PARSER_HEADER_H */]
 375 m4_divert_pop(0)