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