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c++: minor stylistic changes
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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 /// (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
184 /// Constructor for valueless symbols.
185 basic_symbol (typename Base::kind_type t]b4_locations_if([,
186 const location_type& l])[);
187
188 /// Constructor for symbols with semantic value.
189 basic_symbol (typename Base::kind_type t,
190 const semantic_type& v]b4_locations_if([,
191 const location_type& l])[);
192
193 ~basic_symbol ();
194
195 /// Destructive move, \a s is emptied into this.
196 void move (basic_symbol& s);
197
198 /// The semantic value.
199 semantic_type value;]b4_locations_if([
200
201 /// The location.
202 location_type location;])[
203
204 private:
205 /// Assignment operator.
206 basic_symbol& operator= (const basic_symbol& other);
207 };
208
209 /// Type access provider for token (enum) based symbols.
210 struct by_type
211 {
212 /// Default constructor.
213 by_type ();
214
215 /// Copy constructor.
216 by_type (const by_type& other);
217
218 /// The symbol type as needed by the constructor.
219 typedef token_type kind_type;
220
221 /// Constructor from (external) token numbers.
222 by_type (kind_type t);
223
224 /// Steal the symbol type from \a that.
225 void move (by_type& that);
226
227 /// The (internal) type number (corresponding to \a type).
228 /// -1 when this symbol is empty.
229 symbol_number_type type_get () const;
230
231 /// The token.
232 token_type token () const;
233
234 enum { empty = 0 };
235
236 /// The symbol type.
237 /// -1 when this symbol is empty.
238 token_number_type type;
239 };
240
241 /// "External" symbols: returned by the scanner.
242 typedef basic_symbol<by_type> symbol_type;
243
244 ]b4_symbol_constructor_declare])
245
246
247 # b4_public_types_define
248 # ----------------------
249 # Provide the implementation needed by the public types.
250 m4_define([b4_public_types_define],
251 [[ inline
252 ]b4_parser_class_name[::syntax_error::syntax_error (]b4_locations_if([const location_type& l, ])[const std::string& m)
253 : std::runtime_error (m)]b4_locations_if([
254 , location (l)])[
255 {}
256
257 // basic_symbol.
258 template <typename Base>
259 inline
260 ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol ()
261 : value ()
262 {}
263
264 template <typename Base>
265 inline
266 ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (const basic_symbol& other)
267 : Base (other)
268 , value ()]b4_locations_if([
269 , location (other.location)])[
270 {
271 ]b4_variant_if([b4_symbol_variant([other.type_get ()], [value], [copy],
272 [other.value])],
273 [value = other.value;])[
274 }
275
276
277 template <typename Base>
278 inline
279 ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
280 [typename Base::kind_type t],
281 [const semantic_type& v],
282 b4_locations_if([const location_type& l]))[)
283 : Base (t)
284 , value (]b4_variant_if([], [v])[)]b4_locations_if([
285 , location (l)])[
286 {]b4_variant_if([[
287 (void) v;
288 ]b4_symbol_variant([this->type_get ()], [value], [copy], [v])])[}
289
290 template <typename Base>
291 inline
292 ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (]b4_join(
293 [typename Base::kind_type t],
294 b4_locations_if([const location_type& l]))[)
295 : Base (t)
296 , value ()]b4_locations_if([
297 , location (l)])[
298 {}
299
300 template <typename Base>
301 inline
302 ]b4_parser_class_name[::basic_symbol<Base>::~basic_symbol ()
303 {]b4_variant_if([[
304 // User destructor.
305 symbol_number_type yytype = this->type_get ();
306 switch (yytype)
307 {
308 ]b4_symbol_foreach([b4_symbol_destructor])dnl
309 [ default:
310 break;
311 }
312
313 // Type destructor.
314 ]b4_symbol_variant([[yytype]], [[value]], [[template destroy]])])[
315 }
316
317 template <typename Base>
318 inline
319 void
320 ]b4_parser_class_name[::basic_symbol<Base>::move (basic_symbol& s)
321 {
322 super_type::move(s);
323 ]b4_variant_if([b4_symbol_variant([this->type_get ()], [value], [move],
324 [s.value])],
325 [value = s.value;])[]b4_locations_if([
326 location = s.location;])[
327 }
328
329 // by_type.
330 inline
331 ]b4_parser_class_name[::by_type::by_type ()
332 : type (empty)
333 {}
334
335 inline
336 ]b4_parser_class_name[::by_type::by_type (const by_type& other)
337 : type (other.type)
338 {}
339
340 inline
341 ]b4_parser_class_name[::by_type::by_type (token_type t)
342 : type (yytranslate_ (t))
343 {}
344
345 inline
346 void
347 ]b4_parser_class_name[::by_type::move (by_type& that)
348 {
349 type = that.type;
350 that.type = empty;
351 }
352
353 inline
354 int
355 ]b4_parser_class_name[::by_type::type_get () const
356 {
357 return type;
358 }
359 ]b4_token_ctor_if([[
360 inline
361 ]b4_parser_class_name[::token_type
362 ]b4_parser_class_name[::by_type::token () const
363 {
364 // YYTOKNUM[NUM] -- (External) token number corresponding to the
365 // (internal) symbol number NUM (which must be that of a token). */
366 static
367 const ]b4_int_type_for([b4_toknum])[
368 yytoken_number_[] =
369 {
370 ]b4_toknum[
371 };
372 return static_cast<token_type> (yytoken_number_[type]);
373 }
374 ]])[]dnl
375 b4_symbol_constructor_define])
376
377
378 # b4_symbol_constructor_declare
379 # b4_symbol_constructor_define
380 # -----------------------------
381 # Declare/define symbol constructors for all the value types.
382 # Use at class-level. Redefined in variant.hh.
383 m4_define([b4_symbol_constructor_declare], [])
384 m4_define([b4_symbol_constructor_define], [])
385
386
387 # b4_yytranslate_define
388 # ---------------------
389 # Define yytranslate_. Sometimes used in the header file,
390 # sometimes in the cc file.
391 m4_define([b4_yytranslate_define],
392 [[ // Symbol number corresponding to token number t.
393 inline
394 ]b4_parser_class_name[::token_number_type
395 ]b4_parser_class_name[::yytranslate_ (]b4_token_ctor_if([token_type],
396 [int])[ t)
397 {
398 static
399 const token_number_type
400 translate_table[] =
401 {
402 ]b4_translate[
403 };
404 const unsigned int user_token_number_max_ = ]b4_user_token_number_max[;
405 const token_number_type undef_token_ = ]b4_undef_token_number[;
406
407 if (static_cast<int>(t) <= yyeof_)
408 return yyeof_;
409 else if (static_cast<unsigned int> (t) <= user_token_number_max_)
410 return translate_table[t];
411 else
412 return undef_token_;
413 }
414 ]])
415
416
417 # b4_lhs_value([TYPE])
418 # --------------------
419 # Expansion of $<TYPE>$.
420 m4_define([b4_lhs_value],
421 [b4_symbol_value([yyval], [$1])])
422
423
424 # b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
425 # --------------------------------------
426 # Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
427 # symbols on RHS.
428 m4_define([b4_rhs_value],
429 [b4_symbol_value([yysemantic_stack_@{($1) - ($2)@}], [$3])])
430
431
432 # b4_lhs_location()
433 # -----------------
434 # Expansion of @$.
435 m4_define([b4_lhs_location],
436 [(yyloc)])
437
438
439 # b4_rhs_location(RULE-LENGTH, NUM)
440 # ---------------------------------
441 # Expansion of @NUM, where the current rule has RULE-LENGTH symbols
442 # on RHS.
443 m4_define([b4_rhs_location],
444 [(yylocation_stack_@{($1) - ($2)@})])
445
446
447 # b4_parse_param_decl
448 # -------------------
449 # Extra formal arguments of the constructor.
450 # Change the parameter names from "foo" into "foo_yyarg", so that
451 # there is no collision bw the user chosen attribute name, and the
452 # argument name in the constructor.
453 m4_define([b4_parse_param_decl],
454 [m4_ifset([b4_parse_param],
455 [m4_map_sep([b4_parse_param_decl_1], [, ], [b4_parse_param])])])
456
457 m4_define([b4_parse_param_decl_1],
458 [$1_yyarg])
459
460
461
462 # b4_parse_param_cons
463 # -------------------
464 # Extra initialisations of the constructor.
465 m4_define([b4_parse_param_cons],
466 [m4_ifset([b4_parse_param],
467 [
468 b4_cc_constructor_calls(b4_parse_param)])])
469 m4_define([b4_cc_constructor_calls],
470 [m4_map_sep([b4_cc_constructor_call], [,
471 ], [$@])])
472 m4_define([b4_cc_constructor_call],
473 [$2 ($2_yyarg)])
474
475 # b4_parse_param_vars
476 # -------------------
477 # Extra instance variables.
478 m4_define([b4_parse_param_vars],
479 [m4_ifset([b4_parse_param],
480 [
481 // User arguments.
482 b4_cc_var_decls(b4_parse_param)])])
483 m4_define([b4_cc_var_decls],
484 [m4_map_sep([b4_cc_var_decl], [
485 ], [$@])])
486 m4_define([b4_cc_var_decl],
487 [ $1;])
488
489
490 ## ---------##
491 ## Values. ##
492 ## ---------##
493
494 # b4_yylloc_default_define
495 # ------------------------
496 # Define YYLLOC_DEFAULT.
497 m4_define([b4_yylloc_default_define],
498 [[/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
499 If N is 0, then set CURRENT to the empty location which ends
500 the previous symbol: RHS[0] (always defined). */
501
502 # ifndef YYLLOC_DEFAULT
503 # define YYLLOC_DEFAULT(Current, Rhs, N) \
504 do \
505 if (N) \
506 { \
507 (Current).begin = YYRHSLOC (Rhs, 1).begin; \
508 (Current).end = YYRHSLOC (Rhs, N).end; \
509 } \
510 else \
511 { \
512 (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end; \
513 } \
514 while (/*CONSTCOND*/ false)
515 # endif
516 ]])