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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 (void) yysym;
351 switch (yytype)
352 {
353 ]b4_symbol_foreach([b4_symbol_destructor])dnl
354 [ default:
355 break;
356 }
357
358 // Type destructor.
359 ]b4_symbol_variant([[yytype]], [[value]], [[template destroy]])])[
360 Base::clear ();
361 }
362
363 template <typename Base>
364 inline
365 bool
366 ]b4_parser_class_name[::basic_symbol<Base>::empty () const
367 {
368 return Base::type_get () == empty_symbol;
369 }
370
371 template <typename Base>
372 inline
373 void
374 ]b4_parser_class_name[::basic_symbol<Base>::move (basic_symbol& s)
375 {
376 super_type::move(s);
377 ]b4_variant_if([b4_symbol_variant([this->type_get ()], [value], [move],
378 [s.value])],
379 [value = s.value;])[]b4_locations_if([
380 location = s.location;])[
381 }
382
383 // by_type.
384 inline
385 ]b4_parser_class_name[::by_type::by_type ()
386 : type (empty_symbol)
387 {}
388
389 inline
390 ]b4_parser_class_name[::by_type::by_type (const by_type& other)
391 : type (other.type)
392 {}
393
394 inline
395 ]b4_parser_class_name[::by_type::by_type (token_type t)
396 : type (yytranslate_ (t))
397 {}
398
399 inline
400 void
401 ]b4_parser_class_name[::by_type::clear ()
402 {
403 type = empty_symbol;
404 }
405
406 inline
407 void
408 ]b4_parser_class_name[::by_type::move (by_type& that)
409 {
410 type = that.type;
411 that.clear ();
412 }
413
414 inline
415 int
416 ]b4_parser_class_name[::by_type::type_get () const
417 {
418 return type;
419 }
420 ]b4_token_ctor_if([[
421 inline
422 ]b4_parser_class_name[::token_type
423 ]b4_parser_class_name[::by_type::token () const
424 {
425 // YYTOKNUM[NUM] -- (External) token number corresponding to the
426 // (internal) symbol number NUM (which must be that of a token). */
427 static
428 const ]b4_int_type_for([b4_toknum])[
429 yytoken_number_[] =
430 {
431 ]b4_toknum[
432 };
433 return static_cast<token_type> (yytoken_number_[type]);
434 }
435 ]])[]dnl
436 b4_symbol_constructor_define])
437
438
439 # b4_symbol_constructor_declare
440 # b4_symbol_constructor_define
441 # -----------------------------
442 # Declare/define symbol constructors for all the value types.
443 # Use at class-level. Redefined in variant.hh.
444 m4_define([b4_symbol_constructor_declare], [])
445 m4_define([b4_symbol_constructor_define], [])
446
447
448 # b4_yytranslate_define
449 # ---------------------
450 # Define yytranslate_. Sometimes used in the header file,
451 # sometimes in the cc file.
452 m4_define([b4_yytranslate_define],
453 [[ // Symbol number corresponding to token number t.
454 inline
455 ]b4_parser_class_name[::token_number_type
456 ]b4_parser_class_name[::yytranslate_ (]b4_token_ctor_if([token_type],
457 [int])[ t)
458 {
459 static
460 const token_number_type
461 translate_table[] =
462 {
463 ]b4_translate[
464 };
465 const unsigned int user_token_number_max_ = ]b4_user_token_number_max[;
466 const token_number_type undef_token_ = ]b4_undef_token_number[;
467
468 if (static_cast<int>(t) <= yyeof_)
469 return yyeof_;
470 else if (static_cast<unsigned int> (t) <= user_token_number_max_)
471 return translate_table[t];
472 else
473 return undef_token_;
474 }
475 ]])
476
477
478 # b4_lhs_value([TYPE])
479 # --------------------
480 # Expansion of $<TYPE>$.
481 m4_define([b4_lhs_value],
482 [b4_symbol_value([yyval], [$1])])
483
484
485 # b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
486 # --------------------------------------
487 # Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
488 # symbols on RHS.
489 m4_define([b4_rhs_value],
490 [b4_symbol_value([yysemantic_stack_@{($1) - ($2)@}], [$3])])
491
492
493 # b4_lhs_location()
494 # -----------------
495 # Expansion of @$.
496 m4_define([b4_lhs_location],
497 [(yyloc)])
498
499
500 # b4_rhs_location(RULE-LENGTH, NUM)
501 # ---------------------------------
502 # Expansion of @NUM, where the current rule has RULE-LENGTH symbols
503 # on RHS.
504 m4_define([b4_rhs_location],
505 [(yylocation_stack_@{($1) - ($2)@})])
506
507
508 # b4_parse_param_decl
509 # -------------------
510 # Extra formal arguments of the constructor.
511 # Change the parameter names from "foo" into "foo_yyarg", so that
512 # there is no collision bw the user chosen attribute name, and the
513 # argument name in the constructor.
514 m4_define([b4_parse_param_decl],
515 [m4_ifset([b4_parse_param],
516 [m4_map_sep([b4_parse_param_decl_1], [, ], [b4_parse_param])])])
517
518 m4_define([b4_parse_param_decl_1],
519 [$1_yyarg])
520
521
522
523 # b4_parse_param_cons
524 # -------------------
525 # Extra initialisations of the constructor.
526 m4_define([b4_parse_param_cons],
527 [m4_ifset([b4_parse_param],
528 [
529 b4_cc_constructor_calls(b4_parse_param)])])
530 m4_define([b4_cc_constructor_calls],
531 [m4_map_sep([b4_cc_constructor_call], [,
532 ], [$@])])
533 m4_define([b4_cc_constructor_call],
534 [$2 ($2_yyarg)])
535
536 # b4_parse_param_vars
537 # -------------------
538 # Extra instance variables.
539 m4_define([b4_parse_param_vars],
540 [m4_ifset([b4_parse_param],
541 [
542 // User arguments.
543 b4_cc_var_decls(b4_parse_param)])])
544 m4_define([b4_cc_var_decls],
545 [m4_map_sep([b4_cc_var_decl], [
546 ], [$@])])
547 m4_define([b4_cc_var_decl],
548 [ $1;])
549
550
551 ## ---------##
552 ## Values. ##
553 ## ---------##
554
555 # b4_yylloc_default_define
556 # ------------------------
557 # Define YYLLOC_DEFAULT.
558 m4_define([b4_yylloc_default_define],
559 [[/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
560 If N is 0, then set CURRENT to the empty location which ends
561 the previous symbol: RHS[0] (always defined). */
562
563 # ifndef YYLLOC_DEFAULT
564 # define YYLLOC_DEFAULT(Current, Rhs, N) \
565 do \
566 if (N) \
567 { \
568 (Current).begin = YYRHSLOC (Rhs, 1).begin; \
569 (Current).end = YYRHSLOC (Rhs, N).end; \
570 } \
571 else \
572 { \
573 (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end; \
574 } \
575 while (/*CONSTCOND*/ false)
576 # endif
577 ]])
578
579 ## -------- ##
580 ## Checks. ##
581 ## -------- ##
582
583 b4_token_ctor_if([b4_variant_if([],
584 [b4_fatal_at(b4_percent_define_get_loc(api.token.constructor),
585 [cannot use '%s' without '%s'],
586 [%define api.token.constructor],
587 [%define api.value.type variant]))])])