data/glr.cc

   1 m4_divert(-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               [m4_fatal(b4_skeleton[: using %defines is mandatory])])
  56
  57 m4_include(b4_pkgdatadir/[c++.m4])
  58 m4_include(b4_pkgdatadir/[location.cc])
  59
  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::b4_parser_class_name::semantic_type *yyvaluep],
  80                              [yyvaluep]],
  81     [[const b4_namespace::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::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::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 namespace ]b4_namespace[
 121 {
 122 ]dnl In this section, the parse param are the original parse_params.
 123 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
 124 [  /// Build a parser object.
 125   ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)
 126     : yycdebug_ (&std::cerr)]b4_parse_param_cons[
 127   {
 128   }
 129
 130   ]b4_parser_class_name::~b4_parser_class_name[ ()
 131   {
 132   }
 133
 134   int
 135   ]b4_parser_class_name[::parse ()
 136   {
 137     return ::yyparse (*this]b4_user_args[);
 138   }
 139
 140 #if YYDEBUG
 141   /*--------------------.
 142   | Print this symbol.  |
 143   `--------------------*/
 144
 145   inline void
 146   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 147                            const semantic_type* yyvaluep, const location_type* yylocationp)
 148   {
 149     /* Pacify ``unused variable'' warnings.  */
 150     YYUSE (yyvaluep);
 151     YYUSE (yylocationp);
 152     switch (yytype)
 153       {
 154   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
 155 [        default:
 156           break;
 157       }
 158   }
 159
 160
 161   void
 162   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 163                            const semantic_type* yyvaluep, const location_type* yylocationp)
 164   {
 165     *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
 166                << ' ' << yytname[yytype] << " ("
 167                << *yylocationp << ": ";
 168     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
 169     *yycdebug_ << ')';
 170   }
 171
 172   std::ostream&
 173   ]b4_parser_class_name[::debug_stream () const
 174   {
 175     return *yycdebug_;
 176   }
 177
 178   void
 179   ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
 180   {
 181     yycdebug_ = &o;
 182   }
 183
 184
 185   ]b4_parser_class_name[::debug_level_type
 186   ]b4_parser_class_name[::debug_level () const
 187   {
 188     return ::yydebug;
 189   }
 190
 191   void
 192   ]b4_parser_class_name[::set_debug_level (debug_level_type l)
 193   {
 194     ::yydebug = l;
 195   }
 196
 197 #endif /* ! YYDEBUG */
 198 ]m4_popdef([b4_parse_param])dnl
 199 [} // namespace ]b4_namespace[
 200
 201 ]])
 202
 203
 204 # Let glr.c believe that the user arguments include the parser itself.
 205 m4_ifset([b4_parse_param],
 206 [m4_pushdef([b4_parse_param],
 207             m4_dquote([[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]],]
 208 m4_defn([b4_parse_param])))],
 209 [m4_pushdef([b4_parse_param],
 210             [[[[b4_namespace::b4_parser_class_name& yyparser], [[yyparser]]]]])
 211 ])
 212 m4_include(b4_pkgdatadir/[glr.c])
 213 m4_popdef([b4_parse_param])
 214
 215 @output @output_header_name@
 216 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 217   [2002, 2003, 2004, 2005, 2006])[
 218
 219 /* C++ GLR parser skeleton written by Akim Demaille.  */
 220
 221 #ifndef PARSER_HEADER_H
 222 # define PARSER_HEADER_H
 223
 224 #include <string>
 225 #include <iostream>
 226
 227 /* Using locations.  */
 228 #define YYLSP_NEEDED ]b4_locations_flag[
 229
 230 namespace ]b4_namespace[
 231 {
 232   class position;
 233   class location;
 234 }
 235
 236 ]m4_ifdef([b4_start_header],
 237 [[/* Copy the %start-header blocks.  */
 238 ]b4_user_start_header])[
 239
 240 #include "location.hh"
 241
 242 /* Enabling traces.  */
 243 #ifndef YYDEBUG
 244 # define YYDEBUG ]b4_debug_flag[
 245 #endif
 246
 247 /* Enabling verbose error messages.  */
 248 #ifdef YYERROR_VERBOSE
 249 # undef YYERROR_VERBOSE
 250 # define YYERROR_VERBOSE 1
 251 #else
 252 # define YYERROR_VERBOSE ]b4_error_verbose_flag[
 253 #endif
 254
 255 /* Enabling the token table.  */
 256 #ifndef YYTOKEN_TABLE
 257 # define YYTOKEN_TABLE ]b4_token_table[
 258 #endif
 259
 260 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 261    If N is 0, then set CURRENT to the empty location which ends
 262    the previous symbol: RHS[0] (always defined).  */
 263
 264 #ifndef YYLLOC_DEFAULT
 265 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 266     do                                                                  \
 267       if (N)                                                            \
 268         {                                                               \
 269           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 270           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 271         }                                                               \
 272       else                                                              \
 273         {                                                               \
 274           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 275         }                                                               \
 276     while (/*CONSTCOND*/ 0)
 277 #endif
 278
 279 namespace ]b4_namespace[
 280 {
 281   /// A Bison parser.
 282   class ]b4_parser_class_name[
 283   {
 284   public:
 285     /// Symbol semantic values.
 286 #ifndef YYSTYPE
 287 ]m4_ifdef([b4_stype],
 288 [    union semantic_type
 289 b4_user_stype
 290         ;],
 291 [    typedef int semantic_type;])[
 292 #else
 293     typedef YYSTYPE semantic_type;
 294 #endif
 295     /// Symbol locations.
 296     typedef ]b4_location_type[ location_type;
 297     /// Tokens.
 298     struct token
 299     {
 300       ]b4_token_enums(b4_tokens)[
 301     };
 302     /// Token type.
 303     typedef token::yytokentype token_type;
 304
 305     /// Build a parser object.
 306     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 307     virtual ~]b4_parser_class_name[ ();
 308
 309     /// Parse.
 310     /// \returns  0 iff parsing succeeded.
 311     virtual int parse ();
 312
 313     /// The current debugging stream.
 314     std::ostream& debug_stream () const;
 315     /// Set the current debugging stream.
 316     void set_debug_stream (std::ostream &);
 317
 318     /// Type for debugging levels.
 319     typedef int debug_level_type;
 320     /// The current debugging level.
 321     debug_level_type debug_level () const;
 322     /// Set the current debugging level.
 323     void set_debug_level (debug_level_type l);
 324
 325   private:
 326
 327   public:
 328     /// Report a syntax error.
 329     /// \param loc    where the syntax error is found.
 330     /// \param msg    a description of the syntax error.
 331     virtual void error (const location_type& loc, const std::string& msg);
 332   private:
 333
 334 #if YYDEBUG
 335   public:
 336     /// \brief Report a symbol value on the debug stream.
 337     /// \param yytype       The token type.
 338     /// \param yyvaluep     Its semantic value.
 339     /// \param yylocationp  Its location.
 340     virtual void yy_symbol_value_print_ (int yytype,
 341                                          const semantic_type* yyvaluep,
 342                                          const location_type* yylocationp);
 343     /// \brief Report a symbol on the debug stream.
 344     /// \param yytype       The token type.
 345     /// \param yyvaluep     Its semantic value.
 346     /// \param yylocationp  Its location.
 347     virtual void yy_symbol_print_ (int yytype,
 348                                    const semantic_type* yyvaluep,
 349                                    const location_type* yylocationp);
 350   private:
 351 #endif /* ! YYDEBUG */
 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     /* Debugging.  */
 365     std::ostream* yycdebug_;
 366 ]b4_parse_param_vars[
 367   };
 368
 369 ]dnl Redirections for glr.c.
 370 m4_ifset([b4_global_tokens_and_yystype],
 371 [b4_token_defines(b4_tokens)])
 372 [
 373 #ifndef YYSTYPE
 374 # define YYSTYPE ]b4_namespace[::]b4_parser_class_name[::semantic_type
 375 #endif
 376 #ifndef YYLTYPE
 377 # define YYLTYPE ]b4_namespace[::]b4_parser_class_name[::location_type
 378 #endif
 379
 380 }
 381
 382 ]m4_ifdef([b4_end_header],
 383 [[/* Copy the %end-header blocks.  */
 384 ]b4_end_header])[]dnl
 385
 386 [#endif /* ! defined PARSER_HEADER_H */]