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_stype],
 121 [    union semantic_type
 122     {
 123 b4_user_stype
 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     /// Token type.
 158     typedef token::yytokentype token_type;
 159
 160     /// A complete symbol.
 161     ///
 162     /// Expects its Base type to provide access to the symbol type
 163     /// via type_get().
 164     ///
 165     /// Provide access to semantic value]b4_locations_if([ and location])[.
 166     template <typename Base>
 167     struct basic_symbol : Base
 168     {
 169       /// Alias to Base.
 170       typedef Base super_type;
 171
 172       /// Default constructor.
 173       inline basic_symbol ();
 174
 175       /// Copy constructor.
 176       inline basic_symbol (const basic_symbol& other);
 177
 178       /// Constructor for valueless symbols.
 179       inline basic_symbol (typename Base::value_type t]b4_locations_if([,
 180                            const location_type& l])[);
 181
 182       /// Constructor for symbols with semantic value.
 183       inline basic_symbol (typename Base::value_type t,
 184                            const semantic_type& v]b4_locations_if([,
 185                            const location_type& l])[);
 186
 187       ~basic_symbol ();
 188
 189       /// Destructive move, \a s is emptied into this.
 190       inline void move (basic_symbol& s);
 191
 192       /// The semantic value.
 193       semantic_type value;]b4_locations_if([
 194
 195       /// The location.
 196       location_type location;])[
 197
 198     private:
 199       /// Assignment operator.
 200       basic_symbol& operator= (const basic_symbol& other);
 201     };
 202
 203     /// Type access provider for token (enum) based symbols.
 204     struct by_type
 205     {
 206       /// Default constructor.
 207       inline by_type ();
 208
 209       /// Copy constructor.
 210       inline by_type (const by_type& other);
 211
 212       /// Constructor.
 213       inline by_type (token_type t);
 214
 215       /// Steal the type of \a that.
 216       void move (by_type& that);
 217
 218       /// The symbol type.
 219       ///
 220       /// -1 when this symbol is empty.
 221       int type;
 222
 223       /// The type (corresponding to \a type).
 224       ///
 225       /// -1 when this symbol is empty.
 226       inline int type_get () const;
 227
 228       /// The token.
 229       inline token_type token () const;
 230
 231       /// The type used to store the symbol type.
 232       typedef token_type value_type;
 233     };
 234
 235     /// "External" symbols: returned by the scanner.
 236     typedef basic_symbol<by_type> symbol_type;
 237
 238 ]b4_symbol_constructor_declare])
 239
 240
 241 # b4_public_types_define
 242 # ----------------------
 243 # Provide the implementation needed by the public types.
 244 m4_define([b4_public_types_define],
 245 [[  inline
 246   ]b4_parser_class_name[::syntax_error::syntax_error (]b4_locations_if([const location_type& l, ])[const std::string& m)
 247     : std::runtime_error (m)]b4_locations_if([
 248     , location (l)])[
 249   {}
 250
 251   // basic_symbol.
 252   template <typename Base>
 253   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol ()
 254     : value ()
 255   {}
 256
 257   template <typename Base>
 258   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (const basic_symbol& other)
 259     : Base (other)
 260     , value ()]b4_locations_if([
 261     , location (other.location)])[
 262   {
 263     ]b4_variant_if([b4_symbol_variant([other.type_get ()], [value], [copy],
 264                                       [other.value])],
 265                    [value = other.value;])[
 266   }
 267
 268
 269   template <typename Base>
 270   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
 271           [typename Base::value_type t],
 272           [const semantic_type& v],
 273           b4_locations_if([const location_type& l]))[)
 274     : Base (t)
 275     , value (]b4_variant_if([], [v])[)]b4_locations_if([
 276     , location (l)])[
 277   {]b4_variant_if([[
 278     (void) v;
 279     ]b4_symbol_variant([this->type_get ()], [value], [copy], [v])])[}
 280
 281   template <typename Base>
 282   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
 283           [typename Base::value_type t],
 284           b4_locations_if([const location_type& l]))[)
 285     : Base (t)
 286     , value ()]b4_locations_if([
 287     , location (l)])[
 288   {}
 289
 290   template <typename Base>
 291   inline
 292   ]b4_parser_class_name[::basic_symbol<Base>::~basic_symbol ()
 293   {]b4_variant_if([[
 294     // User destructor.
 295     int yytype = this->type_get ();
 296     switch (yytype)
 297     {
 298 ]b4_symbol_foreach([b4_symbol_destructor])dnl
 299 [   default:
 300       break;
 301     }
 302
 303     // Type destructor.
 304   ]b4_symbol_variant([[yytype]], [[value]], [[template destroy]])])[
 305   }
 306
 307   template <typename Base>
 308   void
 309   ]b4_parser_class_name[::basic_symbol<Base>::move (basic_symbol& s)
 310   {
 311     super_type::move(s);
 312     ]b4_variant_if([b4_symbol_variant([this->type_get ()], [value], [move],
 313                                       [s.value])],
 314                    [value = s.value;])[]b4_locations_if([
 315     location = s.location;])[
 316   }
 317
 318   // by_type.
 319   ]b4_parser_class_name[::by_type::by_type ()
 320      : type (-1)
 321   {}
 322
 323   ]b4_parser_class_name[::by_type::by_type (const by_type& other)
 324     : type (other.type)
 325   {}
 326
 327   ]b4_parser_class_name[::by_type::by_type (token_type t)
 328     : type (yytranslate_ (t))
 329   {}
 330
 331   inline
 332   void
 333   ]b4_parser_class_name[::by_type::move (by_type& that)
 334   {
 335     type = that.type;
 336     that.type = -1;
 337   }
 338
 339   int
 340   ]b4_parser_class_name[::by_type::type_get () const
 341   {
 342     return type;
 343   }
 344 ]b4_token_ctor_if([[
 345   ]b4_parser_class_name[::token_type
 346   ]b4_parser_class_name[::by_type::token () const
 347   {
 348     // YYTOKNUM[NUM] -- (External) token number corresponding to the
 349     // (internal) symbol number NUM (which must be that of a token).  */
 350     static
 351     const ]b4_int_type_for([b4_toknum])[
 352     yytoken_number_[] =
 353     {
 354   ]b4_toknum[
 355     };
 356     return static_cast<token_type> (yytoken_number_[type]);
 357   }
 358 ]])[]dnl
 359 b4_symbol_constructor_define])
 360
 361
 362 # b4_symbol_constructor_declare
 363 # b4_symbol_constructor_define
 364 # -----------------------------
 365 # Declare/define symbol constructors for all the value types.
 366 # Use at class-level.  Redefined in variant.hh.
 367 m4_define([b4_symbol_constructor_declare], [])
 368 m4_define([b4_symbol_constructor_define], [])
 369
 370
 371 # b4_yytranslate_define
 372 # ---------------------
 373 # Define yytranslate_.  Sometimes used in the header file,
 374 # sometimes in the cc file.
 375 m4_define([b4_yytranslate_define],
 376 [[  // Symbol number corresponding to token number t.
 377   ]b4_parser_class_name[::token_number_type
 378   ]b4_parser_class_name[::yytranslate_ (]b4_token_ctor_if([token_type],
 379                                                           [int])[ t)
 380   {
 381     static
 382     const token_number_type
 383     translate_table[] =
 384     {
 385 ]b4_translate[
 386     };
 387     const unsigned int user_token_number_max_ = ]b4_user_token_number_max[;
 388     const token_number_type undef_token_ = ]b4_undef_token_number[;
 389
 390     if (static_cast<int>(t) <= yyeof_)
 391       return yyeof_;
 392     else if (static_cast<unsigned int> (t) <= user_token_number_max_)
 393       return translate_table[t];
 394     else
 395       return undef_token_;
 396   }
 397 ]])
 398
 399
 400 # b4_lhs_value([TYPE])
 401 # --------------------
 402 # Expansion of $<TYPE>$.
 403 m4_define([b4_lhs_value],
 404 [b4_symbol_value([yyval], [$1])])
 405
 406
 407 # b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
 408 # --------------------------------------
 409 # Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
 410 # symbols on RHS.
 411 m4_define([b4_rhs_value],
 412 [b4_symbol_value([yysemantic_stack_@{($1) - ($2)@}], [$3])])
 413
 414
 415 # b4_lhs_location()
 416 # -----------------
 417 # Expansion of @$.
 418 m4_define([b4_lhs_location],
 419 [(yyloc)])
 420
 421
 422 # b4_rhs_location(RULE-LENGTH, NUM)
 423 # ---------------------------------
 424 # Expansion of @NUM, where the current rule has RULE-LENGTH symbols
 425 # on RHS.
 426 m4_define([b4_rhs_location],
 427 [(yylocation_stack_@{($1) - ($2)@})])
 428
 429
 430 # b4_parse_param_decl
 431 # -------------------
 432 # Extra formal arguments of the constructor.
 433 # Change the parameter names from "foo" into "foo_yyarg", so that
 434 # there is no collision bw the user chosen attribute name, and the
 435 # argument name in the constructor.
 436 m4_define([b4_parse_param_decl],
 437 [m4_ifset([b4_parse_param],
 438           [m4_map_sep([b4_parse_param_decl_1], [, ], [b4_parse_param])])])
 439
 440 m4_define([b4_parse_param_decl_1],
 441 [$1_yyarg])
 442
 443
 444
 445 # b4_parse_param_cons
 446 # -------------------
 447 # Extra initialisations of the constructor.
 448 m4_define([b4_parse_param_cons],
 449           [m4_ifset([b4_parse_param],
 450                     [
 451       b4_cc_constructor_calls(b4_parse_param)])])
 452 m4_define([b4_cc_constructor_calls],
 453           [m4_map_sep([b4_cc_constructor_call], [,
 454       ], [$@])])
 455 m4_define([b4_cc_constructor_call],
 456           [$2 ($2_yyarg)])
 457
 458 # b4_parse_param_vars
 459 # -------------------
 460 # Extra instance variables.
 461 m4_define([b4_parse_param_vars],
 462           [m4_ifset([b4_parse_param],
 463                     [
 464     // User arguments.
 465 b4_cc_var_decls(b4_parse_param)])])
 466 m4_define([b4_cc_var_decls],
 467           [m4_map_sep([b4_cc_var_decl], [
 468 ], [$@])])
 469 m4_define([b4_cc_var_decl],
 470           [    $1;])
 471
 472
 473 ## ---------##
 474 ## Values.  ##
 475 ## ---------##
 476
 477 # b4_yylloc_default_define
 478 # ------------------------
 479 # Define YYLLOC_DEFAULT.
 480 m4_define([b4_yylloc_default_define],
 481 [[/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
 482    If N is 0, then set CURRENT to the empty location which ends
 483    the previous symbol: RHS[0] (always defined).  */
 484
 485 # ifndef YYLLOC_DEFAULT
 486 #  define YYLLOC_DEFAULT(Current, Rhs, N)                               \
 487     do                                                                  \
 488       if (N)                                                            \
 489         {                                                               \
 490           (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
 491           (Current).end    = YYRHSLOC (Rhs, N).end;                     \
 492         }                                                               \
 493       else                                                              \
 494         {                                                               \
 495           (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
 496         }                                                               \
 497     while (/*CONSTCOND*/ false)
 498 # endif
 499 ]])