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