data/glr.cc

   1 # C++ GLR skeleton for Bison
   2
   3 # Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
   4 # 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's easy: make yyparser 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 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_percent_define(locations)], [])
  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], [  ], [ :])[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 ]b4_symbol_foreach([b4_symbol_printer])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 # Let glr.c believe that the user arguments include the parser itself.
 207 m4_ifset([b4_parse_param],
 208 [m4_pushdef([b4_parse_param],
 209             m4_dquote([[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]],]
 210 m4_defn([b4_parse_param])))],
 211 [m4_pushdef([b4_parse_param],
 212             [[[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]]]])
 213 ])
 214 m4_include(b4_pkgdatadir/[glr.c])
 215 m4_popdef([b4_parse_param])
 216
 217 m4_divert_push(0)
 218 @output(b4_spec_defines_file@)@
 219 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 220              [2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010])[
 221
 222 /* C++ GLR parser skeleton written by Akim Demaille.  */
 223
 224 #ifndef PARSER_HEADER_H
 225 # define PARSER_HEADER_H
 226
 227 ]b4_percent_code_get([[requires]])[
 228
 229 #include <stdexcept>
 230 #include <string>
 231 #include <iostream>
 232 ]b4_percent_define_ifdef([[location_type]], [],
 233                          [[#include "location.hh"]])[
 234
 235 /* Using locations.  */
 236 #define YYLSP_NEEDED ]b4_locations_if([1], [0])[
 237
 238 /* Enabling traces.  */
 239 #ifndef YYDEBUG
 240 # define YYDEBUG ]b4_parse_trace_if([1], [0])[
 241 #endif
 242
 243 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 244    If N is 0, then set CURRENT to the empty location which ends
 245    the previous symbol: RHS[0] (always defined).  */
 246
 247 #ifndef YYLLOC_DEFAULT
 248 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 249     do                                                                  \
 250       if (N)                                                            \
 251         {                                                               \
 252           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 253           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 254         }                                                               \
 255       else                                                              \
 256         {                                                               \
 257           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 258         }                                                               \
 259     while (/*CONSTCOND*/ 0)
 260 #endif
 261
 262 ]b4_namespace_open[
 263   /// A Bison parser.
 264   class ]b4_parser_class_name[
 265   {
 266   public:
 267 ]b4_public_types_declare[
 268
 269     /// Build a parser object.
 270     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 271     virtual ~]b4_parser_class_name[ ();
 272
 273     /// Parse.
 274     /// \returns  0 iff parsing succeeded.
 275     virtual int parse ();
 276
 277     /// The current debugging stream.
 278     std::ostream& debug_stream () const;
 279     /// Set the current debugging stream.
 280     void set_debug_stream (std::ostream &);
 281
 282     /// Type for debugging levels.
 283     typedef int debug_level_type;
 284     /// The current debugging level.
 285     debug_level_type debug_level () const;
 286     /// Set the current debugging level.
 287     void set_debug_level (debug_level_type l);
 288
 289   public:
 290     /// Report a syntax error.
 291     /// \param loc    where the syntax error is found.
 292     /// \param msg    a description of the syntax error.
 293     virtual void error (const location_type& loc, const std::string& msg);
 294
 295 #if YYDEBUG
 296   public:
 297     /// \brief Report a symbol value on the debug stream.
 298     /// \param yytype       The token type.
 299     /// \param yyvaluep     Its semantic value.
 300     /// \param yylocationp  Its location.
 301     virtual void yy_symbol_value_print_ (int yytype,
 302                                          const semantic_type* yyvaluep,
 303                                          const location_type* yylocationp);
 304     /// \brief Report a symbol on the debug stream.
 305     /// \param yytype       The token type.
 306     /// \param yyvaluep     Its semantic value.
 307     /// \param yylocationp  Its location.
 308     virtual void yy_symbol_print_ (int yytype,
 309                                    const semantic_type* yyvaluep,
 310                                    const location_type* yylocationp);
 311   private:
 312     /* Debugging.  */
 313     std::ostream* yycdebug_;
 314 #endif
 315
 316     /// \brief Reclaim the memory associated to a symbol.
 317     /// \param yymsg        Why this token is reclaimed.
 318     /// \param yytype       The symbol type.
 319     /// \param yyvaluep     Its semantic value.
 320     /// \param yylocationp  Its location.
 321     inline void yydestruct_ (const char* yymsg,
 322                              int yytype,
 323                              semantic_type* yyvaluep,
 324                              location_type* yylocationp);
 325
 326 ]b4_parse_param_vars[
 327   };
 328
 329 ]dnl Redirections for glr.c.
 330 b4_percent_define_flag_if([[global_tokens_and_yystype]],
 331 [b4_token_defines(b4_tokens)])
 332 [
 333 #ifndef YYSTYPE
 334 # define YYSTYPE ]b4_namespace_ref[::]b4_parser_class_name[::semantic_type
 335 #endif
 336 #ifndef YYLTYPE
 337 # define YYLTYPE ]b4_namespace_ref[::]b4_parser_class_name[::location_type
 338 #endif
 339
 340 ]b4_namespace_close[
 341
 342 ]b4_percent_code_get([[provides]])[]dnl
 343
 344 [#endif /* ! defined PARSER_HEADER_H */]
 345 m4_divert_pop(0)