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 b4_percent_define_ifdef([[location_type]], [],
  57                         [m4_include(b4_pkgdatadir/[location.cc])])
  58
  59 m4_define([b4_parser_class_name],
  60           [b4_percent_define_get([[parser_class_name]])])
  61
  62 # Save the parse parameters.
  63 m4_define([b4_parse_param_orig], m4_defn([b4_parse_param]))
  64
  65
  66 # b4_yy_symbol_print_generate
  67 # ---------------------------
  68 # Bypass the default implementation to generate the "yy_symbol_print"
  69 # and "yy_symbol_value_print" functions.
  70 m4_define([b4_yy_symbol_print_generate],
  71 [[
  72 /*--------------------.
  73 | Print this symbol.  |
  74 `--------------------*/
  75
  76 ]b4_c_ansi_function_def([yy_symbol_print],
  77     [static void],
  78     [[FILE *],               []],
  79     [[int yytype],           [yytype]],
  80     [[const b4_namespace_ref::b4_parser_class_name::semantic_type *yyvaluep],
  81                              [yyvaluep]],
  82     [[const b4_namespace_ref::b4_parser_class_name::location_type *yylocationp],
  83                              [yylocationp]],
  84     b4_parse_param)[
  85 {
  86 ]b4_parse_param_use[]dnl
  87 [  yyparser.yy_symbol_print_ (yytype, yyvaluep]b4_locations_if([, yylocationp])[);
  88 }
  89 ]])
  90
  91
  92 # Declare yyerror.
  93 m4_append([b4_post_prologue],
  94 [b4_syncline([@oline@], [@ofile@])
  95
  96 b4_c_ansi_function_decl([yyerror],
  97     [static void],
  98     [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
  99     b4_parse_param,
 100     [[const char* msg], [msg]])])
 101
 102
 103 # Define yyerror.
 104 m4_append([b4_epilogue],
 105 [b4_syncline([@oline@], [@ofile@])[
 106 /*------------------.
 107 | Report an error.  |
 108 `------------------*/
 109
 110 ]b4_c_ansi_function_def([yyerror],
 111     [static void],
 112     [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 113     b4_parse_param,
 114     [[const char* msg], [msg]])[
 115 {
 116 ]b4_parse_param_use[]dnl
 117 [  yyparser.error (*yylocationp, msg);
 118 }
 119
 120
 121 ]b4_namespace_open[
 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[)]m4_ifset([b4_parse_param], [
 126     :])[
 127 #if YYDEBUG
 128     ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
 129       yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 130 #endif]b4_parse_param_cons[
 131   {
 132   }
 133
 134   ]b4_parser_class_name::~b4_parser_class_name[ ()
 135   {
 136   }
 137
 138   int
 139   ]b4_parser_class_name[::parse ()
 140   {
 141     return ::yyparse (*this]b4_user_args[);
 142   }
 143
 144 #if YYDEBUG
 145   /*--------------------.
 146   | Print this symbol.  |
 147   `--------------------*/
 148
 149   inline void
 150   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 151                            const semantic_type* yyvaluep, const location_type* yylocationp)
 152   {
 153     /* Pacify ``unused variable'' warnings.  */
 154     YYUSE (yyvaluep);
 155     YYUSE (yylocationp);
 156     switch (yytype)
 157       {
 158   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
 159 [        default:
 160           break;
 161       }
 162   }
 163
 164
 165   void
 166   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 167                            const semantic_type* yyvaluep, const location_type* yylocationp)
 168   {
 169     *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
 170                << ' ' << yytname[yytype] << " ("
 171                << *yylocationp << ": ";
 172     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
 173     *yycdebug_ << ')';
 174   }
 175
 176   std::ostream&
 177   ]b4_parser_class_name[::debug_stream () const
 178   {
 179     return *yycdebug_;
 180   }
 181
 182   void
 183   ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
 184   {
 185     yycdebug_ = &o;
 186   }
 187
 188
 189   ]b4_parser_class_name[::debug_level_type
 190   ]b4_parser_class_name[::debug_level () const
 191   {
 192     return yydebug_;
 193   }
 194
 195   void
 196   ]b4_parser_class_name[::set_debug_level (debug_level_type l)
 197   {
 198     yydebug_ = l;
 199   }
 200
 201 #endif
 202 ]m4_popdef([b4_parse_param])dnl
 203 b4_namespace_close[
 204
 205 ]])
 206
 207
 208 # Let glr.c believe that the user arguments include the parser itself.
 209 m4_ifset([b4_parse_param],
 210 [m4_pushdef([b4_parse_param],
 211             m4_dquote([[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]],]
 212 m4_defn([b4_parse_param])))],
 213 [m4_pushdef([b4_parse_param],
 214             [[[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]]]])
 215 ])
 216 m4_include(b4_pkgdatadir/[glr.c])
 217 m4_popdef([b4_parse_param])
 218
 219 m4_divert_push(0)
 220 @output(b4_spec_defines_file@)@
 221 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 222              [2002-2006, 2009-2010])[
 223
 224 /* C++ GLR parser skeleton written by Akim Demaille.  */
 225
 226 #ifndef PARSER_HEADER_H
 227 # define PARSER_HEADER_H
 228
 229 ]b4_percent_code_get([[requires]])[
 230
 231 #include <string>
 232 #include <iostream>
 233 ]b4_percent_define_ifdef([[location_type]], [],
 234                          [[#include "location.hh"]])[
 235
 236 /* Using locations.  */
 237 #define YYLSP_NEEDED ]b4_locations_flag[
 238
 239 /* Enabling traces.  */
 240 #ifndef YYDEBUG
 241 # define YYDEBUG ]b4_debug_flag[
 242 #endif
 243
 244 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 245    If N is 0, then set CURRENT to the empty location which ends
 246    the previous symbol: RHS[0] (always defined).  */
 247
 248 #ifndef YYLLOC_DEFAULT
 249 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 250     do                                                                  \
 251       if (N)                                                            \
 252         {                                                               \
 253           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 254           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 255         }                                                               \
 256       else                                                              \
 257         {                                                               \
 258           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 259         }                                                               \
 260     while (/*CONSTCOND*/ 0)
 261 #endif
 262
 263 ]b4_namespace_open[
 264   /// A Bison parser.
 265   class ]b4_parser_class_name[
 266   {
 267   public:
 268     /// Symbol semantic values.
 269 #ifndef YYSTYPE
 270 ]m4_ifdef([b4_stype],
 271 [    union semantic_type
 272     {
 273 b4_user_stype
 274     };],
 275 [m4_if(b4_tag_seen_flag, 0,
 276 [[    typedef int semantic_type;]],
 277 [[    typedef YYSTYPE semantic_type;]])])[
 278 #else
 279     typedef YYSTYPE semantic_type;
 280 #endif
 281     /// Symbol locations.
 282     typedef ]b4_percent_define_get([[location_type]],
 283                                    [[location]])[ location_type;
 284     /// Tokens.
 285     struct token
 286     {
 287       ]b4_token_enums(b4_tokens)[
 288     };
 289     /// Token type.
 290     typedef token::yytokentype token_type;
 291
 292     /// Build a parser object.
 293     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 294     virtual ~]b4_parser_class_name[ ();
 295
 296     /// Parse.
 297     /// \returns  0 iff parsing succeeded.
 298     virtual int parse ();
 299
 300     /// The current debugging stream.
 301     std::ostream& debug_stream () const;
 302     /// Set the current debugging stream.
 303     void set_debug_stream (std::ostream &);
 304
 305     /// Type for debugging levels.
 306     typedef int debug_level_type;
 307     /// The current debugging level.
 308     debug_level_type debug_level () const;
 309     /// Set the current debugging level.
 310     void set_debug_level (debug_level_type l);
 311
 312   private:
 313
 314   public:
 315     /// Report a syntax error.
 316     /// \param loc    where the syntax error is found.
 317     /// \param msg    a description of the syntax error.
 318     virtual void error (const location_type& loc, const std::string& msg);
 319   private:
 320
 321 #if YYDEBUG
 322   public:
 323     /// \brief Report a symbol value on the debug stream.
 324     /// \param yytype       The token type.
 325     /// \param yyvaluep     Its semantic value.
 326     /// \param yylocationp  Its location.
 327     virtual void yy_symbol_value_print_ (int yytype,
 328                                          const semantic_type* yyvaluep,
 329                                          const location_type* yylocationp);
 330     /// \brief Report a symbol on the debug stream.
 331     /// \param yytype       The token type.
 332     /// \param yyvaluep     Its semantic value.
 333     /// \param yylocationp  Its location.
 334     virtual void yy_symbol_print_ (int yytype,
 335                                    const semantic_type* yyvaluep,
 336                                    const location_type* yylocationp);
 337   private:
 338     /* Debugging.  */
 339     int yydebug_;
 340     std::ostream* yycdebug_;
 341 #endif
 342
 343
 344     /// \brief Reclaim the memory associated to a symbol.
 345     /// \param yymsg        Why this token is reclaimed.
 346     /// \param yytype       The symbol type.
 347     /// \param yyvaluep     Its semantic value.
 348     /// \param yylocationp  Its location.
 349     inline void yydestruct_ (const char* yymsg,
 350                              int yytype,
 351                              semantic_type* yyvaluep,
 352                              location_type* yylocationp);
 353
 354 ]b4_parse_param_vars[
 355   };
 356
 357 ]dnl Redirections for glr.c.
 358 b4_percent_define_flag_if([[global_tokens_and_yystype]],
 359 [b4_token_defines(b4_tokens)])
 360 [
 361 #ifndef YYSTYPE
 362 # define YYSTYPE ]b4_namespace_ref[::]b4_parser_class_name[::semantic_type
 363 #endif
 364 #ifndef YYLTYPE
 365 # define YYLTYPE ]b4_namespace_ref[::]b4_parser_class_name[::location_type
 366 #endif
 367
 368 ]b4_namespace_close[
 369
 370 ]b4_percent_code_get([[provides]])[]dnl
 371
 372 [#endif /* ! defined PARSER_HEADER_H */]
 373 m4_divert_pop(0)