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
 116
 117 # b4_value_type_declare
 118 # ---------------------
 119 # Declare semantic_type.
 120 m4_define([b4_value_type_declare],
 121 [b4_value_type_setup[]dnl
 122 [    /// Symbol semantic values.
 123 ]m4_bmatch(b4_percent_define_get([api.value.type]),
 124 [^%union\|union$],
 125 [[    union semantic_type
 126     {
 127 ]b4_user_union_members[
 128     };]],
 129 [^$], [],
 130 [[    typedef ]b4_percent_define_get([api.value.type])[ semantic_type;]])])
 131
 132
 133 # b4_public_types_declare
 134 # -----------------------
 135 # Define the public types: token, semantic value, location, and so forth.
 136 # Depending on %define token_lex, may be output in the header or source file.
 137 m4_define([b4_public_types_declare],
 138 [[#ifndef ]b4_api_PREFIX[STYPE
 139 ]b4_value_type_declare[
 140 #else
 141     typedef ]b4_api_PREFIX[STYPE semantic_type;
 142 #endif]b4_locations_if([
 143     /// Symbol locations.
 144     typedef b4_percent_define_get([[api.location.type]],
 145                                   [[location]]) location_type;])[
 146
 147     /// Syntax errors thrown from user actions.
 148     struct syntax_error : std::runtime_error
 149     {
 150       syntax_error (]b4_locations_if([const location_type& l, ])[const std::string& m);]b4_locations_if([
 151       location_type location;])[
 152     };
 153
 154     /// Tokens.
 155     struct token
 156     {
 157       ]b4_token_enums[
 158     };
 159
 160     /// (External) token type, as returned by yylex.
 161     typedef token::yytokentype token_type;
 162
 163     /// Internal symbol number.
 164     typedef int symbol_number_type;
 165
 166     /// Internal symbol number for tokens (subsumed by symbol_number_type).
 167     typedef ]b4_int_type_for([b4_translate])[ token_number_type;
 168
 169     /// A complete symbol.
 170     ///
 171     /// Expects its Base type to provide access to the symbol type
 172     /// via type_get().
 173     ///
 174     /// Provide access to semantic value]b4_locations_if([ and location])[.
 175     template <typename Base>
 176     struct basic_symbol : Base
 177     {
 178       /// Alias to Base.
 179       typedef Base super_type;
 180
 181       /// Default constructor.
 182       basic_symbol ();
 183
 184       /// Copy constructor.
 185       basic_symbol (const basic_symbol& other);
 186 ]b4_variant_if([[
 187       /// Constructor for valueless symbols, and symbols from each type.
 188 ]b4_type_foreach([b4_basic_symbol_constructor_declare])], [[
 189       /// Constructor for valueless symbols.
 190       basic_symbol (typename Base::kind_type t]b4_locations_if([,
 191                     const location_type& l])[);]])[
 192
 193       /// Constructor for symbols with semantic value.
 194       basic_symbol (typename Base::kind_type t,
 195                     const semantic_type& v]b4_locations_if([,
 196                     const location_type& l])[);
 197
 198       ~basic_symbol ();
 199
 200       /// Destructive move, \a s is emptied into this.
 201       void move (basic_symbol& s);
 202
 203       /// The semantic value.
 204       semantic_type value;]b4_locations_if([
 205
 206       /// The location.
 207       location_type location;])[
 208
 209     private:
 210       /// Assignment operator.
 211       basic_symbol& operator= (const basic_symbol& other);
 212     };
 213
 214     /// Type access provider for token (enum) based symbols.
 215     struct by_type
 216     {
 217       /// Default constructor.
 218       by_type ();
 219
 220       /// Copy constructor.
 221       by_type (const by_type& other);
 222
 223       /// The symbol type as needed by the constructor.
 224       typedef token_type kind_type;
 225
 226       /// Constructor from (external) token numbers.
 227       by_type (kind_type t);
 228
 229       /// Steal the symbol type from \a that.
 230       void move (by_type& that);
 231
 232       /// The (internal) type number (corresponding to \a type).
 233       /// -1 when this symbol is empty.
 234       symbol_number_type type_get () const;
 235
 236       /// The token.
 237       token_type token () const;
 238
 239       enum { empty = 0 };
 240
 241       /// The symbol type.
 242       /// -1 when this symbol is empty.
 243       token_number_type type;
 244     };
 245
 246     /// "External" symbols: returned by the scanner.
 247     typedef basic_symbol<by_type> symbol_type;
 248
 249 ]b4_symbol_constructor_declare])
 250
 251
 252 # b4_public_types_define
 253 # ----------------------
 254 # Provide the implementation needed by the public types.
 255 m4_define([b4_public_types_define],
 256 [[  inline
 257   ]b4_parser_class_name[::syntax_error::syntax_error (]b4_locations_if([const location_type& l, ])[const std::string& m)
 258     : std::runtime_error (m)]b4_locations_if([
 259     , location (l)])[
 260   {}
 261
 262   // basic_symbol.
 263   template <typename Base>
 264   inline
 265   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol ()
 266     : value ()
 267   {}
 268
 269   template <typename Base>
 270   inline
 271   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (const basic_symbol& other)
 272     : Base (other)
 273     , value ()]b4_locations_if([
 274     , location (other.location)])[
 275   {
 276     ]b4_variant_if([b4_symbol_variant([other.type_get ()], [value], [copy],
 277                                       [other.value])],
 278                    [value = other.value;])[
 279   }
 280
 281
 282   template <typename Base>
 283   inline
 284   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
 285           [typename Base::kind_type t],
 286           [const semantic_type& v],
 287           b4_locations_if([const location_type& l]))[)
 288     : Base (t)
 289     , value (]b4_variant_if([], [v])[)]b4_locations_if([
 290     , location (l)])[
 291   {]b4_variant_if([[
 292     (void) v;
 293     ]b4_symbol_variant([this->type_get ()], [value], [copy], [v])])[}
 294
 295 ]b4_variant_if([[
 296   // Implementation of basic_symbol constructor for each type.
 297 ]b4_type_foreach([b4_basic_symbol_constructor_define])], [[
 298   /// Constructor for valueless symbols.
 299   template <typename Base>
 300   inline
 301   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
 302           [typename Base::kind_type t],
 303           b4_locations_if([const location_type& l]))[)
 304     : Base (t)
 305     , value ()]b4_locations_if([
 306     , location (l)])[
 307   {}]])[
 308
 309   template <typename Base>
 310   inline
 311   ]b4_parser_class_name[::basic_symbol<Base>::~basic_symbol ()
 312   {]b4_variant_if([[
 313     // User destructor.
 314     symbol_number_type yytype = this->type_get ();
 315     switch (yytype)
 316     {
 317 ]b4_symbol_foreach([b4_symbol_destructor])dnl
 318 [   default:
 319       break;
 320     }
 321
 322     // Type destructor.
 323   ]b4_symbol_variant([[yytype]], [[value]], [[template destroy]])])[
 324   }
 325
 326   template <typename Base>
 327   inline
 328   void
 329   ]b4_parser_class_name[::basic_symbol<Base>::move (basic_symbol& s)
 330   {
 331     super_type::move(s);
 332     ]b4_variant_if([b4_symbol_variant([this->type_get ()], [value], [move],
 333                                       [s.value])],
 334                    [value = s.value;])[]b4_locations_if([
 335     location = s.location;])[
 336   }
 337
 338   // by_type.
 339   inline
 340   ]b4_parser_class_name[::by_type::by_type ()
 341      : type (empty)
 342   {}
 343
 344   inline
 345   ]b4_parser_class_name[::by_type::by_type (const by_type& other)
 346     : type (other.type)
 347   {}
 348
 349   inline
 350   ]b4_parser_class_name[::by_type::by_type (token_type t)
 351     : type (yytranslate_ (t))
 352   {}
 353
 354   inline
 355   void
 356   ]b4_parser_class_name[::by_type::move (by_type& that)
 357   {
 358     type = that.type;
 359     that.type = empty;
 360   }
 361
 362   inline
 363   int
 364   ]b4_parser_class_name[::by_type::type_get () const
 365   {
 366     return type;
 367   }
 368 ]b4_token_ctor_if([[
 369   inline
 370   ]b4_parser_class_name[::token_type
 371   ]b4_parser_class_name[::by_type::token () const
 372   {
 373     // YYTOKNUM[NUM] -- (External) token number corresponding to the
 374     // (internal) symbol number NUM (which must be that of a token).  */
 375     static
 376     const ]b4_int_type_for([b4_toknum])[
 377     yytoken_number_[] =
 378     {
 379   ]b4_toknum[
 380     };
 381     return static_cast<token_type> (yytoken_number_[type]);
 382   }
 383 ]])[]dnl
 384 b4_symbol_constructor_define])
 385
 386
 387 # b4_symbol_constructor_declare
 388 # b4_symbol_constructor_define
 389 # -----------------------------
 390 # Declare/define symbol constructors for all the value types.
 391 # Use at class-level.  Redefined in variant.hh.
 392 m4_define([b4_symbol_constructor_declare], [])
 393 m4_define([b4_symbol_constructor_define], [])
 394
 395
 396 # b4_yytranslate_define
 397 # ---------------------
 398 # Define yytranslate_.  Sometimes used in the header file,
 399 # sometimes in the cc file.
 400 m4_define([b4_yytranslate_define],
 401 [[  // Symbol number corresponding to token number t.
 402   inline
 403   ]b4_parser_class_name[::token_number_type
 404   ]b4_parser_class_name[::yytranslate_ (]b4_token_ctor_if([token_type],
 405                                                           [int])[ t)
 406   {
 407     static
 408     const token_number_type
 409     translate_table[] =
 410     {
 411 ]b4_translate[
 412     };
 413     const unsigned int user_token_number_max_ = ]b4_user_token_number_max[;
 414     const token_number_type undef_token_ = ]b4_undef_token_number[;
 415
 416     if (static_cast<int>(t) <= yyeof_)
 417       return yyeof_;
 418     else if (static_cast<unsigned int> (t) <= user_token_number_max_)
 419       return translate_table[t];
 420     else
 421       return undef_token_;
 422   }
 423 ]])
 424
 425
 426 # b4_lhs_value([TYPE])
 427 # --------------------
 428 # Expansion of $<TYPE>$.
 429 m4_define([b4_lhs_value],
 430 [b4_symbol_value([yyval], [$1])])
 431
 432
 433 # b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
 434 # --------------------------------------
 435 # Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
 436 # symbols on RHS.
 437 m4_define([b4_rhs_value],
 438 [b4_symbol_value([yysemantic_stack_@{($1) - ($2)@}], [$3])])
 439
 440
 441 # b4_lhs_location()
 442 # -----------------
 443 # Expansion of @$.
 444 m4_define([b4_lhs_location],
 445 [(yyloc)])
 446
 447
 448 # b4_rhs_location(RULE-LENGTH, NUM)
 449 # ---------------------------------
 450 # Expansion of @NUM, where the current rule has RULE-LENGTH symbols
 451 # on RHS.
 452 m4_define([b4_rhs_location],
 453 [(yylocation_stack_@{($1) - ($2)@})])
 454
 455
 456 # b4_parse_param_decl
 457 # -------------------
 458 # Extra formal arguments of the constructor.
 459 # Change the parameter names from "foo" into "foo_yyarg", so that
 460 # there is no collision bw the user chosen attribute name, and the
 461 # argument name in the constructor.
 462 m4_define([b4_parse_param_decl],
 463 [m4_ifset([b4_parse_param],
 464           [m4_map_sep([b4_parse_param_decl_1], [, ], [b4_parse_param])])])
 465
 466 m4_define([b4_parse_param_decl_1],
 467 [$1_yyarg])
 468
 469
 470
 471 # b4_parse_param_cons
 472 # -------------------
 473 # Extra initialisations of the constructor.
 474 m4_define([b4_parse_param_cons],
 475           [m4_ifset([b4_parse_param],
 476                     [
 477       b4_cc_constructor_calls(b4_parse_param)])])
 478 m4_define([b4_cc_constructor_calls],
 479           [m4_map_sep([b4_cc_constructor_call], [,
 480       ], [$@])])
 481 m4_define([b4_cc_constructor_call],
 482           [$2 ($2_yyarg)])
 483
 484 # b4_parse_param_vars
 485 # -------------------
 486 # Extra instance variables.
 487 m4_define([b4_parse_param_vars],
 488           [m4_ifset([b4_parse_param],
 489                     [
 490     // User arguments.
 491 b4_cc_var_decls(b4_parse_param)])])
 492 m4_define([b4_cc_var_decls],
 493           [m4_map_sep([b4_cc_var_decl], [
 494 ], [$@])])
 495 m4_define([b4_cc_var_decl],
 496           [    $1;])
 497
 498
 499 ## ---------##
 500 ## Values.  ##
 501 ## ---------##
 502
 503 # b4_yylloc_default_define
 504 # ------------------------
 505 # Define YYLLOC_DEFAULT.
 506 m4_define([b4_yylloc_default_define],
 507 [[/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 508    If N is 0, then set CURRENT to the empty location which ends
 509    the previous symbol: RHS[0] (always defined).  */
 510
 511 # ifndef YYLLOC_DEFAULT
 512 #  define YYLLOC_DEFAULT(Current, Rhs, N)                               \
 513     do                                                                  \
 514       if (N)                                                            \
 515         {                                                               \
 516           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 517           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 518         }                                                               \
 519       else                                                              \
 520         {                                                               \
 521           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 522         }                                                               \
 523     while (/*CONSTCOND*/ false)
 524 # endif
 525 ]])
 526
 527 ## -------- ##
 528 ## Checks.  ##
 529 ## -------- ##
 530
 531 b4_token_ctor_if([b4_variant_if([],
 532   [b4_fatal_at(b4_percent_define_get_loc(api.token.constructor),
 533                [cannot use '%s' without '%s'],
 534                [%define api.token.constructor],
 535                [%define api.value.type variant]))])])