data/glr.cc

   1                                                                     -*- C -*-
   2
   3 # C++ GLR skeleton for Bison
   4
   5 # Copyright (C) 2002-2012 Free Software Foundation, Inc.
   6
   7 # This program is free software: you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation, either version 3 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19
  20
  21 # This skeleton produces a C++ class that encapsulates a C glr parser.
  22 # This is in order to reduce the maintenance burden.  The glr.c
  23 # skeleton is clean and pure enough so that there are no real
  24 # problems.  The C++ interface is the same as that of lalr1.cc.  In
  25 # fact, glr.c can replace yacc.c without the user noticing any
  26 # difference, and similarly for glr.cc replacing lalr1.cc.
  27 #
  28 # The passing of parse-params
  29 #
  30 #   The additional arguments are stored as members of the parser
  31 #   object, yyparser.  The C routines need to carry yyparser
  32 #   throughout the C parser; that easy: just let yyparser become an
  33 #   additional parse-param.  But because the C++ skeleton needs to
  34 #   know the "real" original parse-param, we save them
  35 #   (b4_parse_param_orig).  Note that b4_parse_param is overquoted
  36 #   (and c.m4 strips one level of quotes).  This is a PITA, and
  37 #   explains why there are so many levels of quotes.
  38 #
  39 # The locations
  40 #
  41 #   We use location.cc just like lalr1.cc, but because glr.c stores
  42 #   the locations in a (C++) union, the position and location classes
  43 #   must not have a constructor.  Therefore, contrary to lalr1.cc, we
  44 #   must not define "b4_location_constructors".  As a consequence the
  45 #   user must initialize the first positions (in particular the
  46 #   filename member).
  47
  48 # We require a pure interface using locations.
  49 m4_define([b4_locations_flag], [1])
  50 m4_define([b4_pure_flag],      [1])
  51
  52 # The header is mandatory.
  53 b4_defines_if([],
  54               [b4_fatal([b4_skeleton[: using %%defines is mandatory]])])
  55
  56 m4_include(b4_pkgdatadir/[c++.m4])
  57 b4_percent_define_ifdef([[location_type]], [],
  58                         [m4_include(b4_pkgdatadir/[location.cc])])
  59
  60 m4_define([b4_parser_class_name],
  61           [b4_percent_define_get([[parser_class_name]])])
  62
  63 # Save the parse parameters.
  64 m4_define([b4_parse_param_orig], m4_defn([b4_parse_param]))
  65
  66
  67 # b4_yy_symbol_print_generate
  68 # ---------------------------
  69 # Bypass the default implementation to generate the "yy_symbol_print"
  70 # and "yy_symbol_value_print" functions.
  71 m4_define([b4_yy_symbol_print_generate],
  72 [[
  73 /*--------------------.
  74 | Print this symbol.  |
  75 `--------------------*/
  76
  77 ]b4_c_ansi_function_def([yy_symbol_print],
  78     [static void],
  79     [[FILE *],               []],
  80     [[int yytype],           [yytype]],
  81     [[const b4_namespace_ref::b4_parser_class_name::semantic_type *yyvaluep],
  82                              [yyvaluep]],
  83     [[const b4_namespace_ref::b4_parser_class_name::location_type *yylocationp],
  84                              [yylocationp]],
  85     b4_parse_param)[
  86 {
  87 ]b4_parse_param_use[]dnl
  88 [  yyparser.yy_symbol_print_ (yytype, yyvaluep]b4_locations_if([, yylocationp])[);
  89 }
  90 ]])
  91
  92
  93 # Declare yyerror.
  94 m4_append([b4_post_prologue],
  95 [b4_syncline([@oline@], [@ofile@])
  96
  97 b4_c_ansi_function_decl([yyerror],
  98     [static void],
  99     [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 100     b4_parse_param,
 101     [[const char* msg], [msg]])])
 102
 103
 104 # Define yyerror.
 105 m4_append([b4_epilogue],
 106 [b4_syncline([@oline@], [@ofile@])[
 107 /*------------------.
 108 | Report an error.  |
 109 `------------------*/
 110
 111 ]b4_c_ansi_function_def([yyerror],
 112     [static void],
 113     [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
 114     b4_parse_param,
 115     [[const char* msg], [msg]])[
 116 {
 117 ]b4_parse_param_use[]dnl
 118 [  yyparser.error (*yylocationp, msg);
 119 }
 120
 121
 122 ]b4_namespace_open[
 123 ]dnl In this section, the parse param are the original parse_params.
 124 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
 125 [  /// Build a parser object.
 126   ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [
 127     :])[
 128 #if YYDEBUG
 129     ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
 130       yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 131 #endif]b4_parse_param_cons[
 132   {
 133   }
 134
 135   ]b4_parser_class_name::~b4_parser_class_name[ ()
 136   {
 137   }
 138
 139   int
 140   ]b4_parser_class_name[::parse ()
 141   {
 142     return ::yyparse (*this]b4_user_args[);
 143   }
 144
 145 #if YYDEBUG
 146   /*--------------------.
 147   | Print this symbol.  |
 148   `--------------------*/
 149
 150   inline void
 151   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 152                            const semantic_type* yyvaluep, const location_type* yylocationp)
 153   {
 154     /* Pacify ``unused variable'' warnings.  */
 155     YYUSE (yyvaluep);
 156     YYUSE (yylocationp);
 157     switch (yytype)
 158       {
 159   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
 160 [        default:
 161           break;
 162       }
 163   }
 164
 165
 166   void
 167   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 168                            const semantic_type* yyvaluep, const location_type* yylocationp)
 169   {
 170     *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
 171                << ' ' << yytname[yytype] << " ("
 172                << *yylocationp << ": ";
 173     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
 174     *yycdebug_ << ')';
 175   }
 176
 177   std::ostream&
 178   ]b4_parser_class_name[::debug_stream () const
 179   {
 180     return *yycdebug_;
 181   }
 182
 183   void
 184   ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
 185   {
 186     yycdebug_ = &o;
 187   }
 188
 189
 190   ]b4_parser_class_name[::debug_level_type
 191   ]b4_parser_class_name[::debug_level () const
 192   {
 193     return yydebug_;
 194   }
 195
 196   void
 197   ]b4_parser_class_name[::set_debug_level (debug_level_type l)
 198   {
 199     yydebug_ = l;
 200   }
 201
 202 #endif
 203 ]m4_popdef([b4_parse_param])dnl
 204 b4_namespace_close[
 205
 206 ]])
 207
 208
 209 # Let glr.c believe that the user arguments include the parser itself.
 210 m4_ifset([b4_parse_param],
 211 [m4_pushdef([b4_parse_param],
 212             m4_dquote([[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]],]
 213 m4_defn([b4_parse_param])))],
 214 [m4_pushdef([b4_parse_param],
 215             [[[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]]]])
 216 ])
 217 m4_include(b4_pkgdatadir/[glr.c])
 218 m4_popdef([b4_parse_param])
 219
 220 m4_divert_push(0)
 221 @output(b4_spec_defines_file@)@
 222 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
 223              [2002-2006, 2009-2011])[
 224
 225 /* C++ GLR parser skeleton written by Akim Demaille.  */
 226
 227 #ifndef PARSER_HEADER_H
 228 # define PARSER_HEADER_H
 229
 230 ]b4_percent_code_get([[requires]])[
 231
 232 #include <string>
 233 #include <iostream>
 234 ]b4_percent_define_ifdef([[location_type]], [],
 235                          [[#include "location.hh"]])[
 236
 237 /* Using locations.  */
 238 #define YYLSP_NEEDED ]b4_locations_flag[
 239
 240 /* Enabling traces.  */
 241 #ifndef YYDEBUG
 242 # define YYDEBUG ]b4_debug_flag[
 243 #endif
 244
 245 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 246    If N is 0, then set CURRENT to the empty location which ends
 247    the previous symbol: RHS[0] (always defined).  */
 248
 249 #ifndef YYLLOC_DEFAULT
 250 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
 251     do                                                                  \
 252       if (N)                                                            \
 253         {                                                               \
 254           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 255           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 256         }                                                               \
 257       else                                                              \
 258         {                                                               \
 259           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 260         }                                                               \
 261     while (/*CONSTCOND*/ 0)
 262 #endif
 263
 264 ]b4_namespace_open[
 265   /// A Bison parser.
 266   class ]b4_parser_class_name[
 267   {
 268   public:
 269     /// Symbol semantic values.
 270 #ifndef YYSTYPE
 271 ]m4_ifdef([b4_stype],
 272 [    union semantic_type
 273     {
 274 b4_user_stype
 275     };],
 276 [m4_if(b4_tag_seen_flag, 0,
 277 [[    typedef int semantic_type;]],
 278 [[    typedef YYSTYPE semantic_type;]])])[
 279 #else
 280     typedef YYSTYPE semantic_type;
 281 #endif
 282     /// Symbol locations.
 283     typedef ]b4_percent_define_get([[location_type]],
 284                                    [[location]])[ location_type;
 285     /// Tokens.
 286     struct token
 287     {
 288       ]b4_token_enums(b4_tokens)[
 289     };
 290     /// Token type.
 291     typedef token::yytokentype token_type;
 292
 293     /// Build a parser object.
 294     ]b4_parser_class_name[ (]b4_parse_param_decl[);
 295     virtual ~]b4_parser_class_name[ ();
 296
 297     /// Parse.
 298     /// \returns  0 iff parsing succeeded.
 299     virtual int parse ();
 300
 301     /// The current debugging stream.
 302     std::ostream& debug_stream () const;
 303     /// Set the current debugging stream.
 304     void set_debug_stream (std::ostream &);
 305
 306     /// Type for debugging levels.
 307     typedef int debug_level_type;
 308     /// The current debugging level.
 309     debug_level_type debug_level () const;
 310     /// Set the current debugging level.
 311     void set_debug_level (debug_level_type l);
 312
 313   private:
 314
 315   public:
 316     /// Report a syntax error.
 317     /// \param loc    where the syntax error is found.
 318     /// \param msg    a description of the syntax error.
 319     virtual void error (const location_type& loc, const std::string& msg);
 320   private:
 321
 322 #if YYDEBUG
 323   public:
 324     /// \brief Report a symbol value on the debug stream.
 325     /// \param yytype       The token type.
 326     /// \param yyvaluep     Its semantic value.
 327     /// \param yylocationp  Its location.
 328     virtual void yy_symbol_value_print_ (int yytype,
 329                                          const semantic_type* yyvaluep,
 330                                          const location_type* yylocationp);
 331     /// \brief Report a symbol on the debug stream.
 332     /// \param yytype       The token type.
 333     /// \param yyvaluep     Its semantic value.
 334     /// \param yylocationp  Its location.
 335     virtual void yy_symbol_print_ (int yytype,
 336                                    const semantic_type* yyvaluep,
 337                                    const location_type* yylocationp);
 338   private:
 339     /* Debugging.  */
 340     int yydebug_;
 341     std::ostream* yycdebug_;
 342 #endif
 343
 344
 345     /// \brief Reclaim the memory associated to a symbol.
 346     /// \param yymsg        Why this token is reclaimed.
 347     /// \param yytype       The symbol type.
 348     /// \param yyvaluep     Its semantic value.
 349     /// \param yylocationp  Its location.
 350     inline void yydestruct_ (const char* yymsg,
 351                              int yytype,
 352                              semantic_type* yyvaluep,
 353                              location_type* yylocationp);
 354
 355 ]b4_parse_param_vars[
 356   };
 357
 358 ]dnl Redirections for glr.c.
 359 b4_percent_define_flag_if([[global_tokens_and_yystype]],
 360 [b4_token_defines(b4_tokens)])
 361 [
 362 #ifndef YYSTYPE
 363 # define YYSTYPE ]b4_namespace_ref[::]b4_parser_class_name[::semantic_type
 364 #endif
 365 #ifndef YYLTYPE
 366 # define YYLTYPE ]b4_namespace_ref[::]b4_parser_class_name[::location_type
 367 #endif
 368
 369 ]b4_namespace_close[
 370
 371 ]b4_percent_code_get([[provides]])[]dnl
 372
 373 [#endif /* ! defined PARSER_HEADER_H */]
 374 m4_divert_pop(0)