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     /// Internal symbol number.
 178     typedef int symbol_number_type;
 179
 180     /// Internal symbol number for tokens (subsumed by symbol_number_type).
 181     typedef ]b4_int_type_for([b4_translate])[ token_number_type;
 182
 183     /// A complete symbol.
 184     ///
 185     /// Expects its Base type to provide access to the symbol type
 186     /// via type_get().
 187     ///
 188     /// Provide access to semantic value]b4_locations_if([ and location])[.
 189     template <typename Base>
 190     struct basic_symbol : Base
 191     {
 192       /// Alias to Base.
 193       typedef Base super_type;
 194
 195       /// Default constructor.
 196       basic_symbol ();
 197
 198       /// Copy constructor.
 199       basic_symbol (const basic_symbol& other);
 200 ]b4_variant_if([[
 201       /// Constructor for valueless symbols, and symbols from each type.
 202 ]b4_type_foreach([b4_basic_symbol_constructor_declare])], [[
 203       /// Constructor for valueless symbols.
 204       basic_symbol (typename Base::kind_type t]b4_locations_if([,
 205                     const location_type& l])[);]])[
 206
 207       /// Constructor for symbols with semantic value.
 208       basic_symbol (typename Base::kind_type t,
 209                     const semantic_type& v]b4_locations_if([,
 210                     const location_type& l])[);
 211
 212       ~basic_symbol ();
 213
 214       /// Destructive move, \a s is emptied into this.
 215       void move (basic_symbol& s);
 216
 217       /// The semantic value.
 218       semantic_type value;]b4_locations_if([
 219
 220       /// The location.
 221       location_type location;])[
 222
 223     private:
 224       /// Assignment operator.
 225       basic_symbol& operator= (const basic_symbol& other);
 226     };
 227
 228     /// Type access provider for token (enum) based symbols.
 229     struct by_type
 230     {
 231       /// Default constructor.
 232       by_type ();
 233
 234       /// Copy constructor.
 235       by_type (const by_type& other);
 236
 237       /// The symbol type as needed by the constructor.
 238       typedef token_type kind_type;
 239
 240       /// Constructor from (external) token numbers.
 241       by_type (kind_type t);
 242
 243       /// Steal the symbol type from \a that.
 244       void move (by_type& that);
 245
 246       /// The (internal) type number (corresponding to \a type).
 247       /// -1 when this symbol is empty.
 248       symbol_number_type type_get () const;
 249
 250       /// The token.
 251       token_type token () const;
 252
 253       enum { empty = 0 };
 254
 255       /// The symbol type.
 256       /// -1 when this symbol is empty.
 257       token_number_type type;
 258     };
 259
 260     /// "External" symbols: returned by the scanner.
 261     typedef basic_symbol<by_type> symbol_type;
 262
 263 ]b4_symbol_constructor_declare])
 264
 265
 266 # b4_public_types_define
 267 # ----------------------
 268 # Provide the implementation needed by the public types.
 269 m4_define([b4_public_types_define],
 270 [[  inline
 271   ]b4_parser_class_name[::syntax_error::syntax_error (]b4_locations_if([const location_type& l, ])[const std::string& m)
 272     : std::runtime_error (m)]b4_locations_if([
 273     , location (l)])[
 274   {}
 275
 276   // basic_symbol.
 277   template <typename Base>
 278   inline
 279   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol ()
 280     : value ()
 281   {}
 282
 283   template <typename Base>
 284   inline
 285   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (const basic_symbol& other)
 286     : Base (other)
 287     , value ()]b4_locations_if([
 288     , location (other.location)])[
 289   {
 290     ]b4_variant_if([b4_symbol_variant([other.type_get ()], [value], [copy],
 291                                       [other.value])],
 292                    [value = other.value;])[
 293   }
 294
 295
 296   template <typename Base>
 297   inline
 298   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
 299           [typename Base::kind_type t],
 300           [const semantic_type& v],
 301           b4_locations_if([const location_type& l]))[)
 302     : Base (t)
 303     , value (]b4_variant_if([], [v])[)]b4_locations_if([
 304     , location (l)])[
 305   {]b4_variant_if([[
 306     (void) v;
 307     ]b4_symbol_variant([this->type_get ()], [value], [copy], [v])])[}
 308
 309 ]b4_variant_if([[
 310   // Implementation of basic_symbol constructor for each type.
 311 ]b4_type_foreach([b4_basic_symbol_constructor_define])], [[
 312   /// Constructor for valueless symbols.
 313   template <typename Base>
 314   inline
 315   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
 316           [typename Base::kind_type t],
 317           b4_locations_if([const location_type& l]))[)
 318     : Base (t)
 319     , value ()]b4_locations_if([
 320     , location (l)])[
 321   {}]])[
 322
 323   template <typename Base>
 324   inline
 325   ]b4_parser_class_name[::basic_symbol<Base>::~basic_symbol ()
 326   {]b4_variant_if([[
 327     // User destructor.
 328     symbol_number_type yytype = this->type_get ();
 329     switch (yytype)
 330     {
 331 ]b4_symbol_foreach([b4_symbol_destructor])dnl
 332 [   default:
 333       break;
 334     }
 335
 336     // Type destructor.
 337   ]b4_symbol_variant([[yytype]], [[value]], [[template destroy]])])[
 338   }
 339
 340   template <typename Base>
 341   inline
 342   void
 343   ]b4_parser_class_name[::basic_symbol<Base>::move (basic_symbol& s)
 344   {
 345     super_type::move(s);
 346     ]b4_variant_if([b4_symbol_variant([this->type_get ()], [value], [move],
 347                                       [s.value])],
 348                    [value = s.value;])[]b4_locations_if([
 349     location = s.location;])[
 350   }
 351
 352   // by_type.
 353   inline
 354   ]b4_parser_class_name[::by_type::by_type ()
 355      : type (empty)
 356   {}
 357
 358   inline
 359   ]b4_parser_class_name[::by_type::by_type (const by_type& other)
 360     : type (other.type)
 361   {}
 362
 363   inline
 364   ]b4_parser_class_name[::by_type::by_type (token_type t)
 365     : type (yytranslate_ (t))
 366   {}
 367
 368   inline
 369   void
 370   ]b4_parser_class_name[::by_type::move (by_type& that)
 371   {
 372     type = that.type;
 373     that.type = empty;
 374   }
 375
 376   inline
 377   int
 378   ]b4_parser_class_name[::by_type::type_get () const
 379   {
 380     return type;
 381   }
 382 ]b4_token_ctor_if([[
 383   inline
 384   ]b4_parser_class_name[::token_type
 385   ]b4_parser_class_name[::by_type::token () const
 386   {
 387     // YYTOKNUM[NUM] -- (External) token number corresponding to the
 388     // (internal) symbol number NUM (which must be that of a token).  */
 389     static
 390     const ]b4_int_type_for([b4_toknum])[
 391     yytoken_number_[] =
 392     {
 393   ]b4_toknum[
 394     };
 395     return static_cast<token_type> (yytoken_number_[type]);
 396   }
 397 ]])[]dnl
 398 b4_symbol_constructor_define])
 399
 400
 401 # b4_symbol_constructor_declare
 402 # b4_symbol_constructor_define
 403 # -----------------------------
 404 # Declare/define symbol constructors for all the value types.
 405 # Use at class-level.  Redefined in variant.hh.
 406 m4_define([b4_symbol_constructor_declare], [])
 407 m4_define([b4_symbol_constructor_define], [])
 408
 409
 410 # b4_yytranslate_define
 411 # ---------------------
 412 # Define yytranslate_.  Sometimes used in the header file,
 413 # sometimes in the cc file.
 414 m4_define([b4_yytranslate_define],
 415 [[  // Symbol number corresponding to token number t.
 416   inline
 417   ]b4_parser_class_name[::token_number_type
 418   ]b4_parser_class_name[::yytranslate_ (]b4_token_ctor_if([token_type],
 419                                                           [int])[ t)
 420   {
 421     static
 422     const token_number_type
 423     translate_table[] =
 424     {
 425 ]b4_translate[
 426     };
 427     const unsigned int user_token_number_max_ = ]b4_user_token_number_max[;
 428     const token_number_type undef_token_ = ]b4_undef_token_number[;
 429
 430     if (static_cast<int>(t) <= yyeof_)
 431       return yyeof_;
 432     else if (static_cast<unsigned int> (t) <= user_token_number_max_)
 433       return translate_table[t];
 434     else
 435       return undef_token_;
 436   }
 437 ]])
 438
 439
 440 # b4_lhs_value([TYPE])
 441 # --------------------
 442 # Expansion of $<TYPE>$.
 443 m4_define([b4_lhs_value],
 444 [b4_symbol_value([yyval], [$1])])
 445
 446
 447 # b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
 448 # --------------------------------------
 449 # Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
 450 # symbols on RHS.
 451 m4_define([b4_rhs_value],
 452 [b4_symbol_value([yysemantic_stack_@{($1) - ($2)@}], [$3])])
 453
 454
 455 # b4_lhs_location()
 456 # -----------------
 457 # Expansion of @$.
 458 m4_define([b4_lhs_location],
 459 [(yyloc)])
 460
 461
 462 # b4_rhs_location(RULE-LENGTH, NUM)
 463 # ---------------------------------
 464 # Expansion of @NUM, where the current rule has RULE-LENGTH symbols
 465 # on RHS.
 466 m4_define([b4_rhs_location],
 467 [(yylocation_stack_@{($1) - ($2)@})])
 468
 469
 470 # b4_parse_param_decl
 471 # -------------------
 472 # Extra formal arguments of the constructor.
 473 # Change the parameter names from "foo" into "foo_yyarg", so that
 474 # there is no collision bw the user chosen attribute name, and the
 475 # argument name in the constructor.
 476 m4_define([b4_parse_param_decl],
 477 [m4_ifset([b4_parse_param],
 478           [m4_map_sep([b4_parse_param_decl_1], [, ], [b4_parse_param])])])
 479
 480 m4_define([b4_parse_param_decl_1],
 481 [$1_yyarg])
 482
 483
 484
 485 # b4_parse_param_cons
 486 # -------------------
 487 # Extra initialisations of the constructor.
 488 m4_define([b4_parse_param_cons],
 489           [m4_ifset([b4_parse_param],
 490                     [
 491       b4_cc_constructor_calls(b4_parse_param)])])
 492 m4_define([b4_cc_constructor_calls],
 493           [m4_map_sep([b4_cc_constructor_call], [,
 494       ], [$@])])
 495 m4_define([b4_cc_constructor_call],
 496           [$2 ($2_yyarg)])
 497
 498 # b4_parse_param_vars
 499 # -------------------
 500 # Extra instance variables.
 501 m4_define([b4_parse_param_vars],
 502           [m4_ifset([b4_parse_param],
 503                     [
 504     // User arguments.
 505 b4_cc_var_decls(b4_parse_param)])])
 506 m4_define([b4_cc_var_decls],
 507           [m4_map_sep([b4_cc_var_decl], [
 508 ], [$@])])
 509 m4_define([b4_cc_var_decl],
 510           [    $1;])
 511
 512
 513 ## ---------##
 514 ## Values.  ##
 515 ## ---------##
 516
 517 # b4_yylloc_default_define
 518 # ------------------------
 519 # Define YYLLOC_DEFAULT.
 520 m4_define([b4_yylloc_default_define],
 521 [[/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 522    If N is 0, then set CURRENT to the empty location which ends
 523    the previous symbol: RHS[0] (always defined).  */
 524
 525 # ifndef YYLLOC_DEFAULT
 526 #  define YYLLOC_DEFAULT(Current, Rhs, N)                               \
 527     do                                                                  \
 528       if (N)                                                            \
 529         {                                                               \
 530           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 531           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 532         }                                                               \
 533       else                                                              \
 534         {                                                               \
 535           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 536         }                                                               \
 537     while (/*CONSTCOND*/ false)
 538 # endif
 539 ]])
 540
 541 ## -------- ##
 542 ## Checks.  ##
 543 ## -------- ##
 544
 545 b4_token_ctor_if([b4_variant_if([],
 546   [b4_fatal_at(b4_percent_define_get_loc(api.token.constructor),
 547                [cannot use '%s' without '%s'],
 548                [%define api.token.constructor],
 549                [%define api.value.type variant]))])])