data/c++.m4

   1                                                             -*- Autoconf -*-
   2
   3 # C++ skeleton for Bison
   4
   5 # Copyright (C) 2002-2015 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 # Sanity checks, before defaults installed by c.m4.
  21 b4_percent_define_ifdef([[api.value.union.name]],
  22   [b4_complain_at(b4_percent_define_get_loc([[api.value.union.name]]),
  23                   [named %union is invalid in C++])])
  24
  25 m4_include(b4_pkgdatadir/[c.m4])
  26
  27 # b4_comment(TEXT, [PREFIX])
  28 # --------------------------
  29 # Put TEXT in comment. Prefix all the output lines with PREFIX.
  30 m4_define([b4_comment],
  31 [b4_comment_([$1], [$2// ], [$2// ])])
  32
  33 ## -------- ##
  34 ## Checks.  ##
  35 ## -------- ##
  36
  37 b4_percent_define_check_kind([api.namespace], [code], [deprecated])
  38 b4_percent_define_check_kind([parser_class_name], [code], [deprecated])
  39
  40 ## ---------------- ##
  41 ## Default values.  ##
  42 ## ---------------- ##
  43
  44 b4_percent_define_default([[parser_class_name]], [[parser]])
  45
  46 # Don't do that so that we remember whether we're using a user
  47 # request, or the default value.
  48 #
  49 # b4_percent_define_default([[api.location.type]], [[location]])
  50
  51 b4_percent_define_default([[filename_type]], [[std::string]])
  52 # Make it a warning for those who used betas of Bison 3.0.
  53 b4_percent_define_default([[api.namespace]], m4_defn([b4_prefix]))
  54
  55 b4_percent_define_default([[global_tokens_and_yystype]], [[false]])
  56 b4_percent_define_default([[define_location_comparison]],
  57                           [m4_if(b4_percent_define_get([[filename_type]]),
  58                                  [std::string], [[true]], [[false]])])
  59
  60
  61
  62 ## ----------- ##
  63 ## Namespace.  ##
  64 ## ----------- ##
  65
  66 m4_define([b4_namespace_ref], [b4_percent_define_get([[api.namespace]])])
  67
  68
  69 # Don't permit an empty b4_namespace_ref.  Any '::parser::foo' appended to it
  70 # would compile as an absolute reference with 'parser' in the global namespace.
  71 # b4_namespace_open would open an anonymous namespace and thus establish
  72 # internal linkage.  This would compile.  However, it's cryptic, and internal
  73 # linkage for the parser would be specified in all translation units that
  74 # include the header, which is always generated.  If we ever need to permit
  75 # internal linkage somehow, surely we can find a cleaner approach.
  76 m4_if(m4_bregexp(b4_namespace_ref, [^[   ]*$]), [-1], [],
  77 [b4_complain_at(b4_percent_define_get_loc([[api.namespace]]),
  78                 [[namespace reference is empty]])])
  79
  80 # Instead of assuming the C++ compiler will do it, Bison should reject any
  81 # invalid b4_namepsace_ref that would be converted to a valid
  82 # b4_namespace_open.  The problem is that Bison doesn't always output
  83 # b4_namespace_ref to uncommented code but should reserve the ability to do so
  84 # in future releases without risking breaking any existing user grammars.
  85 # Specifically, don't allow empty names as b4_namespace_open would just convert
  86 # those into anonymous namespaces, and that might tempt some users.
  87 m4_if(m4_bregexp(b4_namespace_ref, [::[  ]*::]), [-1], [],
  88 [b4_complain_at(b4_percent_define_get_loc([[api.namespace]]),
  89                 [[namespace reference has consecutive "::"]])])
  90 m4_if(m4_bregexp(b4_namespace_ref, [::[  ]*$]), [-1], [],
  91 [b4_complain_at(b4_percent_define_get_loc([[api.namespace]]),
  92                 [[namespace reference has a trailing "::"]])])
  93
  94 m4_define([b4_namespace_open],
  95 [b4_user_code([b4_percent_define_get_syncline([[api.namespace]])
  96 [namespace ]m4_bpatsubst(m4_dquote(m4_bpatsubst(m4_dquote(b4_namespace_ref),
  97                                                 [^\(.\)[         ]*::], [\1])),
  98                          [::], [ { namespace ])[ {]])])
  99
 100 m4_define([b4_namespace_close],
 101 [b4_user_code([b4_percent_define_get_syncline([[api.namespace]])
 102 m4_bpatsubst(m4_dquote(m4_bpatsubst(m4_dquote(b4_namespace_ref[ ]),
 103                                     [^\(.\)[     ]*\(::\)?\([^][:]\|:[^:]\)*],
 104                                     [\1])),
 105              [::\([^][:]\|:[^:]\)*], [} ])[} // ]b4_namespace_ref])])
 106
 107
 108 # b4_token_enums
 109 # --------------
 110 # Output the definition of the tokens as enums.
 111 m4_define([b4_token_enums],
 112 [[enum yytokentype
 113       {
 114         ]m4_join([,
 115         ],
 116                  b4_symbol_map([b4_token_enum]))[
 117       };]dnl
 118 ])
 119
 120
 121
 122
 123 ## ----------------- ##
 124 ## Semantic Values.  ##
 125 ## ----------------- ##
 126
 127
 128
 129 # b4_value_type_declare
 130 # ---------------------
 131 # Declare semantic_type.
 132 m4_define([b4_value_type_declare],
 133 [b4_value_type_setup[]dnl
 134 [    /// Symbol semantic values.
 135 ]m4_bmatch(b4_percent_define_get_kind([[api.value.type]]),
 136 [code],
 137 [[    typedef ]b4_percent_define_get([[api.value.type]])[ semantic_type;]],
 138 [m4_bmatch(b4_percent_define_get([[api.value.type]]),
 139 [union\|union-directive],
 140 [[    union semantic_type
 141     {
 142     ]b4_user_union_members[
 143     };]])])dnl
 144 ])
 145
 146
 147 # b4_public_types_declare
 148 # -----------------------
 149 # Define the public types: token, semantic value, location, and so forth.
 150 # Depending on %define token_lex, may be output in the header or source file.
 151 m4_define([b4_public_types_declare],
 152 [[#ifndef ]b4_api_PREFIX[STYPE
 153 ]b4_value_type_declare[
 154 #else
 155     typedef ]b4_api_PREFIX[STYPE semantic_type;
 156 #endif]b4_locations_if([
 157     /// Symbol locations.
 158     typedef b4_percent_define_get([[api.location.type]],
 159                                   [[location]]) location_type;])[
 160
 161     /// Syntax errors thrown from user actions.
 162     struct syntax_error : std::runtime_error
 163     {
 164       syntax_error (]b4_locations_if([const location_type& l, ])[const std::string& m);]b4_locations_if([
 165       location_type location;])[
 166     };
 167
 168     /// Tokens.
 169     struct token
 170     {
 171       ]b4_token_enums[
 172     };
 173
 174     /// (External) token type, as returned by yylex.
 175     typedef token::yytokentype token_type;
 176
 177     /// Symbol type: an internal symbol number.
 178     typedef int symbol_number_type;
 179
 180     /// The symbol type number to denote an empty symbol.
 181     enum { empty_symbol = -2 };
 182
 183     /// Internal symbol number for tokens (subsumed by symbol_number_type).
 184     typedef ]b4_int_type_for([b4_translate])[ token_number_type;
 185
 186     /// A complete symbol.
 187     ///
 188     /// Expects its Base type to provide access to the symbol type
 189     /// via type_get().
 190     ///
 191     /// Provide access to semantic value]b4_locations_if([ and location])[.
 192     template <typename Base>
 193     struct basic_symbol : Base
 194     {
 195       /// Alias to Base.
 196       typedef Base super_type;
 197
 198       /// Default constructor.
 199       basic_symbol ();
 200
 201       /// Copy constructor.
 202       basic_symbol (const basic_symbol& other);
 203 ]b4_variant_if([[
 204       /// Constructor for valueless symbols, and symbols from each type.
 205 ]b4_type_foreach([b4_basic_symbol_constructor_declare])], [[
 206       /// Constructor for valueless symbols.
 207       basic_symbol (typename Base::kind_type t]b4_locations_if([,
 208                     const location_type& l])[);]])[
 209
 210       /// Constructor for symbols with semantic value.
 211       basic_symbol (typename Base::kind_type t,
 212                     const semantic_type& v]b4_locations_if([,
 213                     const location_type& l])[);
 214
 215       /// Destroy the symbol.
 216       ~basic_symbol ();
 217
 218       /// Destroy contents, and record that is empty.
 219       void clear ();
 220
 221       /// Whether empty.
 222       bool empty () const;
 223
 224       /// Destructive move, \a s is emptied into this.
 225       void move (basic_symbol& s);
 226
 227       /// The semantic value.
 228       semantic_type value;]b4_locations_if([
 229
 230       /// The location.
 231       location_type location;])[
 232
 233     private:
 234       /// Assignment operator.
 235       basic_symbol& operator= (const basic_symbol& other);
 236     };
 237
 238     /// Type access provider for token (enum) based symbols.
 239     struct by_type
 240     {
 241       /// Default constructor.
 242       by_type ();
 243
 244       /// Copy constructor.
 245       by_type (const by_type& other);
 246
 247       /// The symbol type as needed by the constructor.
 248       typedef token_type kind_type;
 249
 250       /// Constructor from (external) token numbers.
 251       by_type (kind_type t);
 252
 253       /// Record that this symbol is empty.
 254       void clear ();
 255
 256       /// Steal the symbol type from \a that.
 257       void move (by_type& that);
 258
 259       /// The (internal) type number (corresponding to \a type).
 260       /// \a empty when empty.
 261       symbol_number_type type_get () const;
 262
 263       /// The token.
 264       token_type token () const;
 265
 266       /// The symbol type.
 267       /// \a empty_symbol when empty.
 268       /// An int, not token_number_type, to be able to store empty_symbol.
 269       int type;
 270     };
 271
 272     /// "External" symbols: returned by the scanner.
 273     typedef basic_symbol<by_type> symbol_type;
 274
 275 ]b4_symbol_constructor_declare])
 276
 277
 278 # b4_public_types_define
 279 # ----------------------
 280 # Provide the implementation needed by the public types.
 281 m4_define([b4_public_types_define],
 282 [[  inline
 283   ]b4_parser_class_name[::syntax_error::syntax_error (]b4_locations_if([const location_type& l, ])[const std::string& m)
 284     : std::runtime_error (m)]b4_locations_if([
 285     , location (l)])[
 286   {}
 287
 288   // basic_symbol.
 289   template <typename Base>
 290   inline
 291   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol ()
 292     : value ()
 293   {}
 294
 295   template <typename Base>
 296   inline
 297   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (const basic_symbol& other)
 298     : Base (other)
 299     , value ()]b4_locations_if([
 300     , location (other.location)])[
 301   {
 302     ]b4_variant_if([b4_symbol_variant([other.type_get ()], [value], [copy],
 303                                       [other.value])],
 304                    [value = other.value;])[
 305   }
 306
 307
 308   template <typename Base>
 309   inline
 310   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
 311           [typename Base::kind_type t],
 312           [const semantic_type& v],
 313           b4_locations_if([const location_type& l]))[)
 314     : Base (t)
 315     , value (]b4_variant_if([], [v])[)]b4_locations_if([
 316     , location (l)])[
 317   {]b4_variant_if([[
 318     (void) v;
 319     ]b4_symbol_variant([this->type_get ()], [value], [copy], [v])])[}
 320
 321 ]b4_variant_if([[
 322   // Implementation of basic_symbol constructor for each type.
 323 ]b4_type_foreach([b4_basic_symbol_constructor_define])], [[
 324   /// Constructor for valueless symbols.
 325   template <typename Base>
 326   inline
 327   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
 328           [typename Base::kind_type t],
 329           b4_locations_if([const location_type& l]))[)
 330     : Base (t)
 331     , value ()]b4_locations_if([
 332     , location (l)])[
 333   {}]])[
 334
 335   template <typename Base>
 336   inline
 337   ]b4_parser_class_name[::basic_symbol<Base>::~basic_symbol ()
 338   {
 339     clear ();
 340   }
 341
 342   template <typename Base>
 343   inline
 344   void
 345   ]b4_parser_class_name[::basic_symbol<Base>::clear ()
 346   {]b4_variant_if([[
 347     // User destructor.
 348     symbol_number_type yytype = this->type_get ();
 349     basic_symbol<Base>& yysym = *this;
 350     switch (yytype)
 351     {
 352 ]b4_symbol_foreach([b4_symbol_destructor])dnl
 353 [   default:
 354       break;
 355     }
 356
 357     // Type destructor.
 358   ]b4_symbol_variant([[yytype]], [[value]], [[template destroy]])])[
 359     Base::clear ();
 360   }
 361
 362   template <typename Base>
 363   inline
 364   bool
 365   ]b4_parser_class_name[::basic_symbol<Base>::empty () const
 366   {
 367     return Base::type_get () == empty_symbol;
 368   }
 369
 370   template <typename Base>
 371   inline
 372   void
 373   ]b4_parser_class_name[::basic_symbol<Base>::move (basic_symbol& s)
 374   {
 375     super_type::move(s);
 376     ]b4_variant_if([b4_symbol_variant([this->type_get ()], [value], [move],
 377                                       [s.value])],
 378                    [value = s.value;])[]b4_locations_if([
 379     location = s.location;])[
 380   }
 381
 382   // by_type.
 383   inline
 384   ]b4_parser_class_name[::by_type::by_type ()
 385     : type (empty_symbol)
 386   {}
 387
 388   inline
 389   ]b4_parser_class_name[::by_type::by_type (const by_type& other)
 390     : type (other.type)
 391   {}
 392
 393   inline
 394   ]b4_parser_class_name[::by_type::by_type (token_type t)
 395     : type (yytranslate_ (t))
 396   {}
 397
 398   inline
 399   void
 400   ]b4_parser_class_name[::by_type::clear ()
 401   {
 402     type = empty_symbol;
 403   }
 404
 405   inline
 406   void
 407   ]b4_parser_class_name[::by_type::move (by_type& that)
 408   {
 409     type = that.type;
 410     that.clear ();
 411   }
 412
 413   inline
 414   int
 415   ]b4_parser_class_name[::by_type::type_get () const
 416   {
 417     return type;
 418   }
 419 ]b4_token_ctor_if([[
 420   inline
 421   ]b4_parser_class_name[::token_type
 422   ]b4_parser_class_name[::by_type::token () const
 423   {
 424     // YYTOKNUM[NUM] -- (External) token number corresponding to the
 425     // (internal) symbol number NUM (which must be that of a token).  */
 426     static
 427     const ]b4_int_type_for([b4_toknum])[
 428     yytoken_number_[] =
 429     {
 430   ]b4_toknum[
 431     };
 432     return static_cast<token_type> (yytoken_number_[type]);
 433   }
 434 ]])[]dnl
 435 b4_symbol_constructor_define])
 436
 437
 438 # b4_symbol_constructor_declare
 439 # b4_symbol_constructor_define
 440 # -----------------------------
 441 # Declare/define symbol constructors for all the value types.
 442 # Use at class-level.  Redefined in variant.hh.
 443 m4_define([b4_symbol_constructor_declare], [])
 444 m4_define([b4_symbol_constructor_define], [])
 445
 446
 447 # b4_yytranslate_define
 448 # ---------------------
 449 # Define yytranslate_.  Sometimes used in the header file,
 450 # sometimes in the cc file.
 451 m4_define([b4_yytranslate_define],
 452 [[  // Symbol number corresponding to token number t.
 453   inline
 454   ]b4_parser_class_name[::token_number_type
 455   ]b4_parser_class_name[::yytranslate_ (]b4_token_ctor_if([token_type],
 456                                                           [int])[ t)
 457   {
 458     static
 459     const token_number_type
 460     translate_table[] =
 461     {
 462 ]b4_translate[
 463     };
 464     const unsigned int user_token_number_max_ = ]b4_user_token_number_max[;
 465     const token_number_type undef_token_ = ]b4_undef_token_number[;
 466
 467     if (static_cast<int>(t) <= yyeof_)
 468       return yyeof_;
 469     else if (static_cast<unsigned int> (t) <= user_token_number_max_)
 470       return translate_table[t];
 471     else
 472       return undef_token_;
 473   }
 474 ]])
 475
 476
 477 # b4_lhs_value([TYPE])
 478 # --------------------
 479 # Expansion of $<TYPE>$.
 480 m4_define([b4_lhs_value],
 481 [b4_symbol_value([yyval], [$1])])
 482
 483
 484 # b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
 485 # --------------------------------------
 486 # Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
 487 # symbols on RHS.
 488 m4_define([b4_rhs_value],
 489 [b4_symbol_value([yysemantic_stack_@{($1) - ($2)@}], [$3])])
 490
 491
 492 # b4_lhs_location()
 493 # -----------------
 494 # Expansion of @$.
 495 m4_define([b4_lhs_location],
 496 [(yyloc)])
 497
 498
 499 # b4_rhs_location(RULE-LENGTH, NUM)
 500 # ---------------------------------
 501 # Expansion of @NUM, where the current rule has RULE-LENGTH symbols
 502 # on RHS.
 503 m4_define([b4_rhs_location],
 504 [(yylocation_stack_@{($1) - ($2)@})])
 505
 506
 507 # b4_parse_param_decl
 508 # -------------------
 509 # Extra formal arguments of the constructor.
 510 # Change the parameter names from "foo" into "foo_yyarg", so that
 511 # there is no collision bw the user chosen attribute name, and the
 512 # argument name in the constructor.
 513 m4_define([b4_parse_param_decl],
 514 [m4_ifset([b4_parse_param],
 515           [m4_map_sep([b4_parse_param_decl_1], [, ], [b4_parse_param])])])
 516
 517 m4_define([b4_parse_param_decl_1],
 518 [$1_yyarg])
 519
 520
 521
 522 # b4_parse_param_cons
 523 # -------------------
 524 # Extra initialisations of the constructor.
 525 m4_define([b4_parse_param_cons],
 526           [m4_ifset([b4_parse_param],
 527                     [
 528       b4_cc_constructor_calls(b4_parse_param)])])
 529 m4_define([b4_cc_constructor_calls],
 530           [m4_map_sep([b4_cc_constructor_call], [,
 531       ], [$@])])
 532 m4_define([b4_cc_constructor_call],
 533           [$2 ($2_yyarg)])
 534
 535 # b4_parse_param_vars
 536 # -------------------
 537 # Extra instance variables.
 538 m4_define([b4_parse_param_vars],
 539           [m4_ifset([b4_parse_param],
 540                     [
 541     // User arguments.
 542 b4_cc_var_decls(b4_parse_param)])])
 543 m4_define([b4_cc_var_decls],
 544           [m4_map_sep([b4_cc_var_decl], [
 545 ], [$@])])
 546 m4_define([b4_cc_var_decl],
 547           [    $1;])
 548
 549
 550 ## ---------##
 551 ## Values.  ##
 552 ## ---------##
 553
 554 # b4_yylloc_default_define
 555 # ------------------------
 556 # Define YYLLOC_DEFAULT.
 557 m4_define([b4_yylloc_default_define],
 558 [[/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 559    If N is 0, then set CURRENT to the empty location which ends
 560    the previous symbol: RHS[0] (always defined).  */
 561
 562 # ifndef YYLLOC_DEFAULT
 563 #  define YYLLOC_DEFAULT(Current, Rhs, N)                               \
 564     do                                                                  \
 565       if (N)                                                            \
 566         {                                                               \
 567           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 568           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 569         }                                                               \
 570       else                                                              \
 571         {                                                               \
 572           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 573         }                                                               \
 574     while (/*CONSTCOND*/ false)
 575 # endif
 576 ]])
 577
 578 ## -------- ##
 579 ## Checks.  ##
 580 ## -------- ##
 581
 582 b4_token_ctor_if([b4_variant_if([],
 583   [b4_fatal_at(b4_percent_define_get_loc(api.token.constructor),
 584                [cannot use '%s' without '%s'],
 585                [%define api.token.constructor],
 586                [%define api.value.type variant]))])])