data/c++.m4

   1                                                             -*- Autoconf -*-
   2
   3 # C++ skeleton for Bison
   4
   5 # Copyright (C) 2002-2013 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 m4_include(b4_pkgdatadir/[c.m4])
  21
  22 # b4_comment(TEXT, [PREFIX])
  23 # --------------------------
  24 # Put TEXT in comment. Prefix all the output lines with PREFIX.
  25 m4_define([b4_comment],
  26 [b4_comment_([$1], [$2// ], [$2// ])])
  27
  28
  29 ## ---------------- ##
  30 ## Default values.  ##
  31 ## ---------------- ##
  32
  33 b4_percent_define_default([[parser_class_name]], [[parser]])
  34
  35 # Don't do that so that we remember whether we're using a user
  36 # request, or the default value.
  37 #
  38 # b4_percent_define_default([[api.location.type]], [[location]])
  39
  40 b4_percent_define_default([[filename_type]], [[std::string]])
  41 b4_percent_define_default([[api.namespace]], m4_defn([b4_prefix]))
  42
  43 b4_percent_define_default([[global_tokens_and_yystype]], [[false]])
  44 b4_percent_define_default([[define_location_comparison]],
  45                           [m4_if(b4_percent_define_get([[filename_type]]),
  46                                  [std::string], [[true]], [[false]])])
  47
  48
  49
  50 ## ----------- ##
  51 ## Namespace.  ##
  52 ## ----------- ##
  53
  54 m4_define([b4_namespace_ref], [b4_percent_define_get([[api.namespace]])])
  55
  56
  57 # Don't permit an empty b4_namespace_ref.  Any `::parser::foo' appended to it
  58 # would compile as an absolute reference with `parser' in the global namespace.
  59 # b4_namespace_open would open an anonymous namespace and thus establish
  60 # internal linkage.  This would compile.  However, it's cryptic, and internal
  61 # linkage for the parser would be specified in all translation units that
  62 # include the header, which is always generated.  If we ever need to permit
  63 # internal linkage somehow, surely we can find a cleaner approach.
  64 m4_if(m4_bregexp(b4_namespace_ref, [^[   ]*$]), [-1], [],
  65 [b4_complain_at(b4_percent_define_get_loc([[api.namespace]]),
  66                 [[namespace reference is empty]])])
  67
  68 # Instead of assuming the C++ compiler will do it, Bison should reject any
  69 # invalid b4_namepsace_ref that would be converted to a valid
  70 # b4_namespace_open.  The problem is that Bison doesn't always output
  71 # b4_namespace_ref to uncommented code but should reserve the ability to do so
  72 # in future releases without risking breaking any existing user grammars.
  73 # Specifically, don't allow empty names as b4_namespace_open would just convert
  74 # those into anonymous namespaces, and that might tempt some users.
  75 m4_if(m4_bregexp(b4_namespace_ref, [::[  ]*::]), [-1], [],
  76 [b4_complain_at(b4_percent_define_get_loc([[api.namespace]]),
  77                 [[namespace reference has consecutive "::"]])])
  78 m4_if(m4_bregexp(b4_namespace_ref, [::[  ]*$]), [-1], [],
  79 [b4_complain_at(b4_percent_define_get_loc([[api.namespace]]),
  80                 [[namespace reference has a trailing "::"]])])
  81
  82 m4_define([b4_namespace_open],
  83 [b4_user_code([b4_percent_define_get_syncline([[api.namespace]])
  84 [namespace ]m4_bpatsubst(m4_dquote(m4_bpatsubst(m4_dquote(b4_namespace_ref),
  85                                                 [^\(.\)[         ]*::], [\1])),
  86                          [::], [ { namespace ])[ {]])])
  87
  88 m4_define([b4_namespace_close],
  89 [b4_user_code([b4_percent_define_get_syncline([[api.namespace]])
  90 m4_bpatsubst(m4_dquote(m4_bpatsubst(m4_dquote(b4_namespace_ref[ ]),
  91                                     [^\(.\)[     ]*\(::\)?\([^][:]\|:[^:]\)*],
  92                                     [\1])),
  93              [::\([^][:]\|:[^:]\)*], [} ])[} // ]b4_namespace_ref])])
  94
  95
  96 # b4_token_enums
  97 # --------------
  98 # Output the definition of the tokens as enums.
  99 m4_define([b4_token_enums],
 100 [[enum yytokentype
 101       {
 102         ]m4_join([,
 103         ],
 104                  b4_symbol_map([b4_token_enum]))[
 105       };]dnl
 106 ])
 107
 108
 109
 110
 111 ## ----------------- ##
 112 ## Semantic Values.  ##
 113 ## ----------------- ##
 114
 115 # b4_semantic_type_declare
 116 # ------------------------
 117 # Declare semantic_type.
 118 m4_define([b4_semantic_type_declare],
 119 [    /// Symbol semantic values.
 120 m4_ifdef([b4_stype],
 121 [    union semantic_type
 122     {
 123 b4_user_stype
 124     };],
 125 [m4_if(b4_tag_seen_flag, 0,
 126 [[    typedef int semantic_type;]],
 127 [[    typedef ]b4_api_PREFIX[STYPE semantic_type;]])])])
 128
 129
 130 # b4_public_types_declare
 131 # -----------------------
 132 # Define the public types: token, semantic value, location, and so forth.
 133 # Depending on %define token_lex, may be output in the header or source file.
 134 m4_define([b4_public_types_declare],
 135 [[#ifndef ]b4_api_PREFIX[STYPE
 136 ]b4_semantic_type_declare[
 137 #else
 138     typedef ]b4_api_PREFIX[STYPE semantic_type;
 139 #endif]b4_locations_if([
 140     /// Symbol locations.
 141     typedef b4_percent_define_get([[api.location.type]],
 142                                   [[location]]) location_type;])[
 143
 144     /// Syntax errors thrown from user actions.
 145     struct syntax_error : std::runtime_error
 146     {
 147       syntax_error (]b4_locations_if([const location_type& l, ])[const std::string& m);]b4_locations_if([
 148       location_type location;])[
 149     };
 150
 151     /// Tokens.
 152     struct token
 153     {
 154       ]b4_token_enums[
 155     };
 156
 157     /// (External) token type, as returned by yylex.
 158     typedef token::yytokentype token_type;
 159
 160     /// Internal symbol number.
 161     typedef int symbol_number_type;
 162
 163     /// Internal symbol number for tokens (subsumed by symbol_number_type).
 164     typedef ]b4_int_type_for([b4_translate])[ token_number_type;
 165
 166     /// A complete symbol.
 167     ///
 168     /// Expects its Base type to provide access to the symbol type
 169     /// via type_get().
 170     ///
 171     /// Provide access to semantic value]b4_locations_if([ and location])[.
 172     template <typename Base>
 173     struct basic_symbol : Base
 174     {
 175       /// Alias to Base.
 176       typedef Base super_type;
 177
 178       /// Default constructor.
 179       basic_symbol ();
 180
 181       /// Copy constructor.
 182       basic_symbol (const basic_symbol& other);
 183
 184       /// Constructor for valueless symbols.
 185       basic_symbol (typename Base::kind_type t]b4_locations_if([,
 186                     const location_type& l])[);
 187
 188       /// Constructor for symbols with semantic value.
 189       basic_symbol (typename Base::kind_type t,
 190                     const semantic_type& v]b4_locations_if([,
 191                     const location_type& l])[);
 192
 193       ~basic_symbol ();
 194
 195       /// Destructive move, \a s is emptied into this.
 196       void move (basic_symbol& s);
 197
 198       /// The semantic value.
 199       semantic_type value;]b4_locations_if([
 200
 201       /// The location.
 202       location_type location;])[
 203
 204     private:
 205       /// Assignment operator.
 206       basic_symbol& operator= (const basic_symbol& other);
 207     };
 208
 209     /// Type access provider for token (enum) based symbols.
 210     struct by_type
 211     {
 212       /// Default constructor.
 213       by_type ();
 214
 215       /// Copy constructor.
 216       by_type (const by_type& other);
 217
 218       /// The symbol type as needed by the constructor.
 219       typedef token_type kind_type;
 220
 221       /// Constructor from (external) token numbers.
 222       by_type (kind_type t);
 223
 224       /// Steal the symbol type from \a that.
 225       void move (by_type& that);
 226
 227       /// The (internal) type number (corresponding to \a type).
 228       /// -1 when this symbol is empty.
 229       symbol_number_type type_get () const;
 230
 231       /// The token.
 232       token_type token () const;
 233
 234       enum { empty = 0 };
 235
 236       /// The symbol type.
 237       ///
 238       /// -1 when this symbol is empty.
 239       token_number_type type;
 240     };
 241
 242     /// "External" symbols: returned by the scanner.
 243     typedef basic_symbol<by_type> symbol_type;
 244
 245 ]b4_symbol_constructor_declare])
 246
 247
 248 # b4_public_types_define
 249 # ----------------------
 250 # Provide the implementation needed by the public types.
 251 m4_define([b4_public_types_define],
 252 [[  inline
 253   ]b4_parser_class_name[::syntax_error::syntax_error (]b4_locations_if([const location_type& l, ])[const std::string& m)
 254     : std::runtime_error (m)]b4_locations_if([
 255     , location (l)])[
 256   {}
 257
 258   // basic_symbol.
 259   template <typename Base>
 260   inline
 261   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol ()
 262     : value ()
 263   {}
 264
 265   template <typename Base>
 266   inline
 267   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (const basic_symbol& other)
 268     : Base (other)
 269     , value ()]b4_locations_if([
 270     , location (other.location)])[
 271   {
 272     ]b4_variant_if([b4_symbol_variant([other.type_get ()], [value], [copy],
 273                                       [other.value])],
 274                    [value = other.value;])[
 275   }
 276
 277
 278   template <typename Base>
 279   inline
 280   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
 281           [typename Base::kind_type t],
 282           [const semantic_type& v],
 283           b4_locations_if([const location_type& l]))[)
 284     : Base (t)
 285     , value (]b4_variant_if([], [v])[)]b4_locations_if([
 286     , location (l)])[
 287   {]b4_variant_if([[
 288     (void) v;
 289     ]b4_symbol_variant([this->type_get ()], [value], [copy], [v])])[}
 290
 291   template <typename Base>
 292   inline
 293   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
 294           [typename Base::kind_type t],
 295           b4_locations_if([const location_type& l]))[)
 296     : Base (t)
 297     , value ()]b4_locations_if([
 298     , location (l)])[
 299   {}
 300
 301   template <typename Base>
 302   inline
 303   ]b4_parser_class_name[::basic_symbol<Base>::~basic_symbol ()
 304   {]b4_variant_if([[
 305     // User destructor.
 306     symbol_number_type yytype = this->type_get ();
 307     switch (yytype)
 308     {
 309 ]b4_symbol_foreach([b4_symbol_destructor])dnl
 310 [   default:
 311       break;
 312     }
 313
 314     // Type destructor.
 315   ]b4_symbol_variant([[yytype]], [[value]], [[template destroy]])])[
 316   }
 317
 318   template <typename Base>
 319   inline
 320   void
 321   ]b4_parser_class_name[::basic_symbol<Base>::move (basic_symbol& s)
 322   {
 323     super_type::move(s);
 324     ]b4_variant_if([b4_symbol_variant([this->type_get ()], [value], [move],
 325                                       [s.value])],
 326                    [value = s.value;])[]b4_locations_if([
 327     location = s.location;])[
 328   }
 329
 330   // by_type.
 331   inline
 332   ]b4_parser_class_name[::by_type::by_type ()
 333      : type (empty)
 334   {}
 335
 336   inline
 337   ]b4_parser_class_name[::by_type::by_type (const by_type& other)
 338     : type (other.type)
 339   {}
 340
 341   inline
 342   ]b4_parser_class_name[::by_type::by_type (token_type t)
 343     : type (yytranslate_ (t))
 344   {}
 345
 346   inline
 347   void
 348   ]b4_parser_class_name[::by_type::move (by_type& that)
 349   {
 350     type = that.type;
 351     that.type = empty;
 352   }
 353
 354   inline
 355   int
 356   ]b4_parser_class_name[::by_type::type_get () const
 357   {
 358     return type;
 359   }
 360 ]b4_token_ctor_if([[
 361   inline
 362   ]b4_parser_class_name[::token_type
 363   ]b4_parser_class_name[::by_type::token () const
 364   {
 365     // YYTOKNUM[NUM] -- (External) token number corresponding to the
 366     // (internal) symbol number NUM (which must be that of a token).  */
 367     static
 368     const ]b4_int_type_for([b4_toknum])[
 369     yytoken_number_[] =
 370     {
 371   ]b4_toknum[
 372     };
 373     return static_cast<token_type> (yytoken_number_[type]);
 374   }
 375 ]])[]dnl
 376 b4_symbol_constructor_define])
 377
 378
 379 # b4_symbol_constructor_declare
 380 # b4_symbol_constructor_define
 381 # -----------------------------
 382 # Declare/define symbol constructors for all the value types.
 383 # Use at class-level.  Redefined in variant.hh.
 384 m4_define([b4_symbol_constructor_declare], [])
 385 m4_define([b4_symbol_constructor_define], [])
 386
 387
 388 # b4_yytranslate_define
 389 # ---------------------
 390 # Define yytranslate_.  Sometimes used in the header file,
 391 # sometimes in the cc file.
 392 m4_define([b4_yytranslate_define],
 393 [[  // Symbol number corresponding to token number t.
 394   inline
 395   ]b4_parser_class_name[::token_number_type
 396   ]b4_parser_class_name[::yytranslate_ (]b4_token_ctor_if([token_type],
 397                                                           [int])[ t)
 398   {
 399     static
 400     const token_number_type
 401     translate_table[] =
 402     {
 403 ]b4_translate[
 404     };
 405     const unsigned int user_token_number_max_ = ]b4_user_token_number_max[;
 406     const token_number_type undef_token_ = ]b4_undef_token_number[;
 407
 408     if (static_cast<int>(t) <= yyeof_)
 409       return yyeof_;
 410     else if (static_cast<unsigned int> (t) <= user_token_number_max_)
 411       return translate_table[t];
 412     else
 413       return undef_token_;
 414   }
 415 ]])
 416
 417
 418 # b4_lhs_value([TYPE])
 419 # --------------------
 420 # Expansion of $<TYPE>$.
 421 m4_define([b4_lhs_value],
 422 [b4_symbol_value([yyval], [$1])])
 423
 424
 425 # b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
 426 # --------------------------------------
 427 # Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
 428 # symbols on RHS.
 429 m4_define([b4_rhs_value],
 430 [b4_symbol_value([yysemantic_stack_@{($1) - ($2)@}], [$3])])
 431
 432
 433 # b4_lhs_location()
 434 # -----------------
 435 # Expansion of @$.
 436 m4_define([b4_lhs_location],
 437 [(yyloc)])
 438
 439
 440 # b4_rhs_location(RULE-LENGTH, NUM)
 441 # ---------------------------------
 442 # Expansion of @NUM, where the current rule has RULE-LENGTH symbols
 443 # on RHS.
 444 m4_define([b4_rhs_location],
 445 [(yylocation_stack_@{($1) - ($2)@})])
 446
 447
 448 # b4_parse_param_decl
 449 # -------------------
 450 # Extra formal arguments of the constructor.
 451 # Change the parameter names from "foo" into "foo_yyarg", so that
 452 # there is no collision bw the user chosen attribute name, and the
 453 # argument name in the constructor.
 454 m4_define([b4_parse_param_decl],
 455 [m4_ifset([b4_parse_param],
 456           [m4_map_sep([b4_parse_param_decl_1], [, ], [b4_parse_param])])])
 457
 458 m4_define([b4_parse_param_decl_1],
 459 [$1_yyarg])
 460
 461
 462
 463 # b4_parse_param_cons
 464 # -------------------
 465 # Extra initialisations of the constructor.
 466 m4_define([b4_parse_param_cons],
 467           [m4_ifset([b4_parse_param],
 468                     [
 469       b4_cc_constructor_calls(b4_parse_param)])])
 470 m4_define([b4_cc_constructor_calls],
 471           [m4_map_sep([b4_cc_constructor_call], [,
 472       ], [$@])])
 473 m4_define([b4_cc_constructor_call],
 474           [$2 ($2_yyarg)])
 475
 476 # b4_parse_param_vars
 477 # -------------------
 478 # Extra instance variables.
 479 m4_define([b4_parse_param_vars],
 480           [m4_ifset([b4_parse_param],
 481                     [
 482     // User arguments.
 483 b4_cc_var_decls(b4_parse_param)])])
 484 m4_define([b4_cc_var_decls],
 485           [m4_map_sep([b4_cc_var_decl], [
 486 ], [$@])])
 487 m4_define([b4_cc_var_decl],
 488           [    $1;])
 489
 490
 491 ## ---------##
 492 ## Values.  ##
 493 ## ---------##
 494
 495 # b4_yylloc_default_define
 496 # ------------------------
 497 # Define YYLLOC_DEFAULT.
 498 m4_define([b4_yylloc_default_define],
 499 [[/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 500    If N is 0, then set CURRENT to the empty location which ends
 501    the previous symbol: RHS[0] (always defined).  */
 502
 503 # ifndef YYLLOC_DEFAULT
 504 #  define YYLLOC_DEFAULT(Current, Rhs, N)                               \
 505     do                                                                  \
 506       if (N)                                                            \
 507         {                                                               \
 508           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 509           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 510         }                                                               \
 511       else                                                              \
 512         {                                                               \
 513           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 514         }                                                               \
 515     while (/*CONSTCOND*/ false)
 516 # endif
 517 ]])