data/glr.cc

   1                                                                     -*- C -*-
   2
   3 # C++ GLR skeleton for Bison
   4 # Copyright (C) 2002-2010 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 3 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, see <http://www.gnu.org/licenses/>.
  18
  19
  20 # This skeleton produces a C++ class that encapsulates a C glr parser.
  21 # This is in order to reduce the maintenance burden.  The glr.c
  22 # skeleton is clean and pure enough so that there are no real
  23 # problems.  The C++ interface is the same as that of lalr1.cc.  In
  24 # fact, glr.c can replace yacc.c without the user noticing any
  25 # difference, and similarly for glr.cc replacing lalr1.cc.
  26 #
  27 # The passing of parse-params
  28 #
  29 #   The additional arguments are stored as members of the parser
  30 #   object, yyparser.  The C routines need to carry yyparser
  31 #   throughout the C parser; that easy: just let yyparser become an
  32 #   additional parse-param.  But because the C++ skeleton needs to
  33 #   know the "real" original parse-param, we save them
  34 #   (b4_parse_param_orig).  Note that b4_parse_param is overquoted
  35 #   (and c.m4 strips one level of quotes).  This is a PITA, and
  36 #   explains why there are so many levels of quotes.
  37 #
  38 # The locations
  39 #
  40 #   We use location.cc just like lalr1.cc, but because glr.c stores
  41 #   the locations in a (C++) union, the position and location classes
  42 #   must not have a constructor.  Therefore, contrary to lalr1.cc, we
  43 #   must not define "b4_location_constructors".  As a consequence the
  44 #   user must initialize the first positions (in particular the
  45 #   filename member).
  46
  47 # We require a pure interface using locations.
  48 m4_define([b4_locations_flag], [1])
  49 m4_define([b4_pure_flag],      [1])
  50
  51 # The header is mandatory.
  52 b4_defines_if([],
  53               [b4_fatal([b4_skeleton[: using %%defines is mandatory]])])
  54
  55 m4_include(b4_pkgdatadir/[c++.m4])
  56 m4_include(b4_pkgdatadir/[location.cc])
  57
  58 m4_define([b4_parser_class_name],
  59           [b4_percent_define_get([[parser_class_name]])])
  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_ref::b4_parser_class_name::semantic_type *yyvaluep],
  80                              [yyvaluep]],
  81     [[const b4_namespace_ref::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 [b4_syncline([@oline@], [@ofile@])
  94
  95 b4_c_ansi_function_decl([yyerror],
  96     [static void],
  97     [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
  98     b4_parse_param,
  99     [[const char* msg], [msg]])])
 100
 101
 102 # Define yyerror.
 103 m4_append([b4_epilogue],
 104 [b4_syncline([@oline@], [@ofile@])[
 105 /*------------------.
 106 | Report an error.  |
 107 `------------------*/
 108
 109 ]b4_c_ansi_function_def([yyerror],
 110     [static void],
 111     [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 112     b4_parse_param,
 113     [[const char* msg], [msg]])[
 114 {
 115 ]b4_parse_param_use[]dnl
 116 [  yyparser.error (*yylocationp, msg);
 117 }
 118
 119
 120 ]b4_namespace_open[
 121 ]dnl In this section, the parse param are the original parse_params.
 122 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
 123 [  /// Build a parser object.
 124   ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [
 125     :])[
 126 #if YYDEBUG
 127     ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
 128       yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 129 #endif]b4_parse_param_cons[
 130   {
 131   }
 132
 133   ]b4_parser_class_name::~b4_parser_class_name[ ()
 134   {
 135   }
 136
 137   int
 138   ]b4_parser_class_name[::parse ()
 139   {
 140     return ::yyparse (*this]b4_user_args[);
 141   }
 142
 143 #if YYDEBUG
 144   /*--------------------.
 145   | Print this symbol.  |
 146   `--------------------*/
 147
 148   inline void
 149   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 150                            const semantic_type* yyvaluep, const location_type* yylocationp)
 151   {
 152     /* Pacify ``unused variable'' warnings.  */
 153     YYUSE (yyvaluep);
 154     YYUSE (yylocationp);
 155     switch (yytype)
 156       {
 157   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
 158 [        default:
 159           break;
 160       }
 161   }
 162
 163
 164   void
 165   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 166                            const semantic_type* yyvaluep, const location_type* yylocationp)
 167   {
 168     *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
 169                << ' ' << yytname[yytype] << " ("
 170                << *yylocationp << ": ";
 171     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
 172     *yycdebug_ << ')';
 173   }
 174
 175   std::ostream&
 176   ]b4_parser_class_name[::debug_stream () const
 177   {
 178     return *yycdebug_;
 179   }
 180
 181   void
 182   ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
 183   {
 184     yycdebug_ = &o;
 185   }
 186
 187
 188   ]b4_parser_class_name[::debug_level_type
 189   ]b4_parser_class_name[::debug_level () const
 190   {
 191     return yydebug_;
 192   }
 193
 194   void
 195   ]b4_parser_class_name[::set_debug_level (debug_level_type l)
 196   {
 197     yydebug_ = l;
 198   }
 199
 200 #endif
 201 ]m4_popdef([b4_parse_param])dnl
 202 b4_namespace_close[
 203
 204 ]])
 205
 206
 207 # Let glr.c believe that the user arguments include the parser itself.
 208 m4_ifset([b4_parse_param],
 209 [m4_pushdef([b4_parse_param],
 210             m4_dquote([[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]],]
 211 m4_defn([b4_parse_param])))],
 212 [m4_pushdef([b4_parse_param],
 213             [[[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]]]])
 214 ])
 215 m4_include(b4_pkgdatadir/[glr.c])
 216 m4_popdef([b4_parse_param])
 217
 218 m4_divert_push(0)
 219 @output(b4_spec_defines_file@)@
 220 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 221              [2002-2006, 2009-2010])[
 222
 223 /* C++ GLR parser skeleton written by Akim Demaille.  */
 224
 225 #ifndef PARSER_HEADER_H
 226 # define PARSER_HEADER_H
 227
 228 ]b4_percent_code_get([[requires]])[
 229
 230 #include <string>
 231 #include <iostream>
 232 #include "location.hh"
 233
 234 /* Using locations.  */
 235 #define YYLSP_NEEDED ]b4_locations_flag[
 236
 237 /* Enabling traces.  */
 238 #ifndef YYDEBUG
 239 # define YYDEBUG ]b4_debug_flag[
 240 #endif
 241
 242 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 243    If N is 0, then set CURRENT to the empty location which ends
 244    the previous symbol: RHS[0] (always defined).  */
 245
 246 #ifndef YYLLOC_DEFAULT
 247 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 248     do                                                                  \
 249       if (N)                                                            \
 250         {                                                               \
 251           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 252           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 253         }                                                               \
 254       else                                                              \
 255         {                                                               \
 256           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 257         }                                                               \
 258     while (/*CONSTCOND*/ 0)
 259 #endif
 260
 261 ]b4_namespace_open[
 262   /// A Bison parser.
 263   class ]b4_parser_class_name[
 264   {
 265   public:
 266     /// Symbol semantic values.
 267 #ifndef YYSTYPE
 268 ]m4_ifdef([b4_stype],
 269 [    union semantic_type
 270     {
 271 b4_user_stype
 272     };],
 273 [m4_if(b4_tag_seen_flag, 0,
 274 [[    typedef int semantic_type;]],
 275 [[    typedef YYSTYPE semantic_type;]])])[
 276 #else
 277     typedef YYSTYPE semantic_type;
 278 #endif
 279     /// Symbol locations.
 280     typedef ]b4_percent_define_get([[location_type]])[ location_type;
 281     /// Tokens.
 282     struct token
 283     {
 284       ]b4_token_enums(b4_tokens)[
 285     };
 286     /// Token type.
 287     typedef token::yytokentype token_type;
 288
 289     /// Build a parser object.
 290     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 291     virtual ~]b4_parser_class_name[ ();
 292
 293     /// Parse.
 294     /// \returns  0 iff parsing succeeded.
 295     virtual int parse ();
 296
 297     /// The current debugging stream.
 298     std::ostream& debug_stream () const;
 299     /// Set the current debugging stream.
 300     void set_debug_stream (std::ostream &);
 301
 302     /// Type for debugging levels.
 303     typedef int debug_level_type;
 304     /// The current debugging level.
 305     debug_level_type debug_level () const;
 306     /// Set the current debugging level.
 307     void set_debug_level (debug_level_type l);
 308
 309   private:
 310
 311   public:
 312     /// Report a syntax error.
 313     /// \param loc    where the syntax error is found.
 314     /// \param msg    a description of the syntax error.
 315     virtual void error (const location_type& loc, const std::string& msg);
 316   private:
 317
 318 #if YYDEBUG
 319   public:
 320     /// \brief Report a symbol value on the debug stream.
 321     /// \param yytype       The token type.
 322     /// \param yyvaluep     Its semantic value.
 323     /// \param yylocationp  Its location.
 324     virtual void yy_symbol_value_print_ (int yytype,
 325                                          const semantic_type* yyvaluep,
 326                                          const location_type* yylocationp);
 327     /// \brief Report a symbol on the debug stream.
 328     /// \param yytype       The token type.
 329     /// \param yyvaluep     Its semantic value.
 330     /// \param yylocationp  Its location.
 331     virtual void yy_symbol_print_ (int yytype,
 332                                    const semantic_type* yyvaluep,
 333                                    const location_type* yylocationp);
 334   private:
 335     /* Debugging.  */
 336     int yydebug_;
 337     std::ostream* yycdebug_;
 338 #endif
 339
 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)