1 # C++ skeleton for Bison
3 # Copyright (C) 2002-2012 Free Software Foundation, Inc.
5 # This program is free software: you can redistribute it and/or modify
6 # it under the terms of the GNU General Public License as published by
7 # the Free Software Foundation, either version 3 of the License, or
8 # (at your option) any later version.
10 # This program is distributed in the hope that it will be useful,
11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 # GNU General Public License for more details.
15 # You should have received a copy of the GNU General Public License
16 # along with this program. If not, see <http://www.gnu.org/licenses/>.
18 m4_include(b4_pkgdatadir
/[c
++.m4
])
20 m4_define([b4_parser_class_name
],
21 [b4_percent_define_get([[parser_class_name]])])
23 # The header is mandatory.
25 [b4_fatal([b4_skeleton
[: using %%defines is mandatory
]])])
27 b4_percent_define_ifdef([[location_type]], [],
28 [# Backward compatibility.
29 m4_define([b4_location_constructors
])
30 m4_include(b4_pkgdatadir
/[location
.cc
])])
31 m4_include(b4_pkgdatadir
/[stack
.hh
])
33 # We do want M4 expansion after # for CPP macros.
37 [@
output(b4_spec_defines_file@
)@
38 b4_copyright([Skeleton interface
for Bison
LALR(1) parsers in C
++],
42 ** \file ]b4_spec_defines_file[
43 ** Define the ]b4_namespace_ref[::parser class.
46 /* C++ LALR(1) parser skeleton written by Akim Demaille. */
48 ]b4_cpp_guard_open([b4_spec_defines_file
])[
50 ]b4_percent_code_get([[requires]])[
55 ]b4_percent_define_ifdef([[location_type]], [],
56 [[#include "location.hh"]])[
60 /* Enabling traces. */
62 # define YYDEBUG ]b4_debug_flag[
65 /* Enabling verbose error messages. */
66 #ifdef YYERROR_VERBOSE
67 # undef YYERROR_VERBOSE
68 # define YYERROR_VERBOSE 1
70 # define YYERROR_VERBOSE ]b4_error_verbose_flag[
73 /* Enabling the token table. */
75 # define YYTOKEN_TABLE ]b4_token_table[
81 class ]b4_parser_class_name
[
84 /// Symbol semantic values.
91 [m4_if(b4_tag_seen_flag
, 0,
92 [[ typedef int semantic_type
;]],
93 [[ typedef YYSTYPE semantic_type
;]])])[
95 typedef YYSTYPE semantic_type
;
98 typedef ]b4_percent_define_get([[location_type]],
99 [[location]])[ location_type
;
103 ]b4_token_enums(b4_tokens
)[
106 typedef token::yytokentype token_type
;
108 /// Build a parser object.
109 ]b4_parser_class_name
[ (]b4_parse_param_decl
[);
110 virtual ~]b4_parser_class_name
[ ();
113 /// \returns 0 iff parsing succeeded.
114 virtual int parse ();
117 /// The current debugging stream.
118 std::ostream
& debug_stream () const;
119 /// Set the current debugging stream.
120 void set_debug_stream (std::ostream
&);
122 /// Type for debugging levels.
123 typedef int debug_level_type
;
124 /// The current debugging level.
125 debug_level_type
debug_level () const;
126 /// Set the current debugging level.
127 void set_debug_level (debug_level_type l
);
131 /// Report a syntax error.
132 /// \param loc where the syntax error is found.
133 /// \param msg a description of the syntax error.
134 virtual void error (const location_type
& loc
, const std::string
& msg
);
136 /// Generate an error message.
137 /// \param state the state where the error occurred.
138 /// \param tok the lookahead token.
139 virtual std::string
yysyntax_error_ (int yystate
, int tok
);
142 /// \brief Report a symbol value on the debug stream.
143 /// \param yytype The token type.
144 /// \param yyvaluep Its semantic value.
145 /// \param yylocationp Its location.
146 virtual void yy_symbol_value_print_ (int yytype
,
147 const semantic_type
* yyvaluep
,
148 const location_type
* yylocationp
);
149 /// \brief Report a symbol on the debug stream.
150 /// \param yytype The token type.
151 /// \param yyvaluep Its semantic value.
152 /// \param yylocationp Its location.
153 virtual void yy_symbol_print_ (int yytype
,
154 const semantic_type
* yyvaluep
,
155 const location_type
* yylocationp
);
160 typedef int state_type
;
161 /// State stack type.
162 typedef stack
<state_type
> state_stack_type
;
163 /// Semantic value stack type.
164 typedef stack
<semantic_type
> semantic_stack_type
;
165 /// location stack type.
166 typedef stack
<location_type
> location_stack_type
;
169 state_stack_type yystate_stack_
;
170 /// The semantic value stack.
171 semantic_stack_type yysemantic_stack_
;
172 /// The location stack.
173 location_stack_type yylocation_stack_
;
175 /// Whether the given \c yypact_ value indicates a defaulted state.
176 /// \param yyvalue the value to check
177 static bool yy_pact_value_is_default_ (int yyvalue
);
179 /// Whether the given \c yytable_ value indicates a syntax error.
180 /// \param yyvalue the value to check
181 static bool yy_table_value_is_error_ (int yyvalue
);
183 /// Internal symbol numbers.
184 typedef ]b4_int_type_for([b4_translate
])[ token_number_type
;
186 /// For a state, the index in \a yytable_ of its portion.
187 static const ]b4_int_type_for([b4_pact
])[ yypact_
[];
188 static const ]b4_int_type(b4_pact_ninf
, b4_pact_ninf
)[ yypact_ninf_
;
190 /// For a state, default reduction number.
191 /// Unless\a yytable_ specifies something else to do.
192 /// Zero means the default is an error.
193 static const ]b4_int_type_for([b4_defact
])[ yydefact_
[];
195 static const ]b4_int_type_for([b4_pgoto
])[ yypgoto_
[];
196 static const ]b4_int_type_for([b4_defgoto
])[ yydefgoto_
[];
198 /// What to do in a state.
199 /// \a yytable_[yypact_[s]]: what to do in state \a s.
200 /// - if positive, shift that token.
201 /// - if negative, reduce the rule which number is the opposite.
202 /// - if zero, do what YYDEFACT says.
203 static const ]b4_int_type_for([b4_table
])[ yytable_
[];
204 static const ]b4_int_type(b4_table_ninf
, b4_table_ninf
)[ yytable_ninf_
;
206 static const ]b4_int_type_for([b4_check
])[ yycheck_
[];
208 /// For a state, its accessing symbol.
209 static const ]b4_int_type_for([b4_stos
])[ yystos_
[];
211 /// For a rule, its LHS.
212 static const ]b4_int_type_for([b4_r1
])[ yyr1_
[];
213 /// For a rule, its RHS length.
214 static const ]b4_int_type_for([b4_r2
])[ yyr2_
[];
216 #if YYDEBUG || YYERROR_VERBOSE || YYTOKEN_TABLE
217 /// For a symbol, its name in clear.
218 static const char* const yytname_
[];
219 #endif]b4_error_verbose_if([
221 /// Convert the symbol name \a n to a form suitable for a diagnostic.
222 static std::string
yytnamerr_ (const char *n
);])[
225 /// A type to store symbol numbers and -1.
226 typedef ]b4_int_type_for([b4_rhs
])[ rhs_number_type
;
227 /// A `-1'-separated list of the rules' RHS.
228 static const rhs_number_type yyrhs_
[];
229 /// For each rule, the index of the first RHS symbol in \a yyrhs_.
230 static const ]b4_int_type_for([b4_prhs
])[ yyprhs_
[];
231 /// For each rule, its source line number.
232 static const ]b4_int_type_for([b4_rline
])[ yyrline_
[];
233 /// For each scanner token number, its symbol number.
234 static const ]b4_int_type_for([b4_toknum
])[ yytoken_number_
[];
235 /// Report on the debug stream that the rule \a r is going to be reduced.
236 virtual void yy_reduce_print_ (int r
);
237 /// Print the state stack on the debug stream.
238 virtual void yystack_print_ ();
242 std::ostream
* yycdebug_
;
245 /// Convert a scanner token number \a t to a symbol number.
246 token_number_type
yytranslate_ (int t
);
248 /// \brief Reclaim the memory associated to a symbol.
249 /// \param yymsg Why this token is reclaimed.
250 /// \param yytype The symbol type.
251 /// \param yyvaluep Its semantic value.
252 /// \param yylocationp Its location.
253 inline void yydestruct_ (const char* yymsg
,
255 semantic_type
* yyvaluep
,
256 location_type
* yylocationp
);
258 /// Pop \a n symbols the three stacks.
259 inline void yypop_ (unsigned int n
= 1);
262 static const int yyeof_
;
263 /* LAST_ -- Last index in TABLE_. */
264 static const int yylast_
;
265 static const int yynnts_
;
266 static const int yyempty_
;
267 static const int yyfinal_
;
268 static const int yyterror_
;
269 static const int yyerrcode_
;
270 static const int yyntokens_
;
271 static const unsigned int yyuser_token_number_max_
;
272 static const token_number_type yyundef_token_
;
273 ]b4_parse_param_vars
[
277 ]b4_percent_define_flag_if([[global_tokens_and_yystype]],
278 [b4_token_defines(b4_tokens
)
281 /* Redirection for backward compatibility. */
282 # define YYSTYPE b4_namespace_ref::b4_parser_class_name::semantic_type
285 ]b4_percent_code_get([[provides]])[
286 ]b4_cpp_guard_close([b4_spec_defines_file
])
288 @
output(b4_parser_file_name@
)@
289 b4_copyright([Skeleton implementation
for Bison
LALR(1) parsers in C
++],
291 b4_percent_code_get([[top]])[]dnl
292 m4_if(b4_prefix
, [yy
], [],
294 // Take the name prefix into account.
295 #define yylex b4_prefix[]lex])[
297 /* First part of user declarations. */
298 ]b4_user_pre_prologue
301 #include "@basename(]b4_spec_defines_file[@)"]])[
303 /* User implementation prologue. */
304 ]b4_user_post_prologue
305 b4_percent_code_get
[]dnl
308 # if defined YYENABLE_NLS && YYENABLE_NLS
310 # include <libintl.h> /* FIXME: INFRINGES ON USER NAME SPACE */
311 # define YY_(msgid) dgettext ("bison-runtime", msgid)
315 # define YY_(msgid) msgid
319 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
320 If N is 0, then set CURRENT to the empty location which ends
321 the previous symbol: RHS[0] (always defined). */
323 #define YYRHSLOC(Rhs, K) ((Rhs)[K])
324 #ifndef YYLLOC_DEFAULT
325 # define YYLLOC_DEFAULT(Current, Rhs, N) \
329 (Current).begin = YYRHSLOC (Rhs, 1).begin; \
330 (Current).end = YYRHSLOC (Rhs, N).end; \
334 (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end; \
339 /* Suppress unused-variable warnings by "using" E. */
340 #define YYUSE(e) ((void) (e))
342 /* Enable debugging if requested. */
345 /* A pseudo ostream that takes yydebug_ into account. */
346 # define YYCDEBUG if (yydebug_) (*yycdebug_)
348 # define YY_SYMBOL_PRINT(Title, Type, Value, Location) \
352 *yycdebug_ << Title << ' '; \
353 yy_symbol_print_ ((Type), (Value), (Location)); \
354 *yycdebug_ << std::endl; \
358 # define YY_REDUCE_PRINT(Rule) \
361 yy_reduce_print_ (Rule); \
364 # define YY_STACK_PRINT() \
372 # define YYCDEBUG if (false) std::cerr
373 # define YY_SYMBOL_PRINT(Title, Type, Value, Location)
374 # define YY_REDUCE_PRINT(Rule)
375 # define YY_STACK_PRINT()
377 #endif /* !YYDEBUG */
379 #define yyerrok (yyerrstatus_ = 0)
380 #define yyclearin (yychar = yyempty_)
382 #define YYACCEPT goto yyacceptlab
383 #define YYABORT goto yyabortlab
384 #define YYERROR goto yyerrorlab
385 #define YYRECOVERING() (!!yyerrstatus_)
387 ]b4_namespace_open
[]b4_error_verbose_if([[
389 /* Return YYSTR after stripping away unnecessary quotes and
390 backslashes, so that it's suitable for yyerror. The heuristic is
391 that double-quoting is unnecessary unless the string contains an
392 apostrophe, a comma, or backslash (other than backslash-backslash).
393 YYSTR is taken from yytname. */
395 ]b4_parser_class_name
[::yytnamerr_ (const char *yystr
)
399 std::string yyr
= "";
400 char const *yyp
= yystr
;
407 goto do_not_strip_quotes
;
411 goto do_not_strip_quotes
;
420 do_not_strip_quotes
: ;
427 /// Build a parser object.
428 ]b4_parser_class_name::b4_parser_class_name
[ (]b4_parse_param_decl
[)]m4_ifset([b4_parse_param
], [
431 ]m4_ifset([b4_parse_param
], [ ], [ :])[yydebug_ (false),
432 yycdebug_ (&std::cerr
)]m4_ifset([b4_parse_param
], [,])[
433 #endif]b4_parse_param_cons[
437 ]b4_parser_class_name::~b4_parser_class_name
[ ()
442 /*--------------------------------.
443 | Print this symbol on YYOUTPUT. |
444 `--------------------------------*/
447 ]b4_parser_class_name
[::yy_symbol_value_print_ (int yytype
,
448 const semantic_type
* yyvaluep
, const location_type
* yylocationp
)
452 std::ostream
& yyo
= debug_stream ();
453 std::ostream
& yyoutput
= yyo
;
457 ]m4_map([b4_symbol_actions
], m4_defn([b4_symbol_printers
]))dnl
465 ]b4_parser_class_name
[::yy_symbol_print_ (int yytype
,
466 const semantic_type
* yyvaluep
, const location_type
* yylocationp
)
468 *yycdebug_
<< (yytype
< yyntokens_
? "token" : "nterm")
469 << ' ' << yytname_
[yytype
] << " ("
470 << *yylocationp
<< ": ";
471 yy_symbol_value_print_ (yytype
, yyvaluep
, yylocationp
);
477 ]b4_parser_class_name
[::yydestruct_ (const char* yymsg
,
478 int yytype
, semantic_type
* yyvaluep
, location_type
* yylocationp
)
484 YY_SYMBOL_PRINT (yymsg
, yytype
, yyvaluep
, yylocationp
);
488 ]m4_map([b4_symbol_actions
], m4_defn([b4_symbol_destructors
]))[
495 ]b4_parser_class_name
[::yypop_ (unsigned int n
)
497 yystate_stack_
.pop (n
);
498 yysemantic_stack_
.pop (n
);
499 yylocation_stack_
.pop (n
);
504 ]b4_parser_class_name
[::debug_stream () const
510 ]b4_parser_class_name
[::set_debug_stream (std::ostream
& o
)
516 ]b4_parser_class_name
[::debug_level_type
517 ]b4_parser_class_name
[::debug_level () const
523 ]b4_parser_class_name
[::set_debug_level (debug_level_type l
)
530 ]b4_parser_class_name
[::yy_pact_value_is_default_ (int yyvalue
)
532 return yyvalue
== yypact_ninf_
;
536 ]b4_parser_class_name
[::yy_table_value_is_error_ (int yyvalue
)
538 return yyvalue
== yytable_ninf_
;
542 ]b4_parser_class_name
[::parse ()
544 /// Lookahead and lookahead in internal form.
545 int yychar
= yyempty_
;
553 /* Error handling. */
555 int yyerrstatus_
= 0;
557 /// Semantic value of the lookahead.
558 semantic_type yylval
;
559 /// Location of the lookahead.
560 location_type yylloc
;
561 /// The locations where the error started and ended.
562 location_type yyerror_range
[3];
571 YYCDEBUG
<< "Starting parse" << std::endl
;
573 ]m4_ifdef([b4_initial_action
], [
574 m4_pushdef([b4_at_dollar
], [yylloc
])dnl
575 m4_pushdef([b4_dollar_dollar
], [yylval
])dnl
576 /* User initialization code. */
577 b4_user_initial_action
578 m4_popdef([b4_dollar_dollar
])dnl
579 m4_popdef([b4_at_dollar
])])dnl
581 [ /* Initialize the stacks. The initial state will be pushed in
582 yynewstate, since the latter expects the semantical and the
583 location values to have been already stored, initialize these
584 stacks with a primary value. */
585 yystate_stack_
= state_stack_type (0);
586 yysemantic_stack_
= semantic_stack_type (0);
587 yylocation_stack_
= location_stack_type (0);
588 yysemantic_stack_
.push (yylval
);
589 yylocation_stack_
.push (yylloc
);
593 yystate_stack_
.push (yystate
);
594 YYCDEBUG
<< "Entering state " << yystate
<< std::endl
;
597 if (yystate
== yyfinal_
)
605 /* Try to take a decision without lookahead. */
606 yyn
= yypact_
[yystate
];
607 if (yy_pact_value_is_default_ (yyn
))
610 /* Read a lookahead token. */
611 if (yychar
== yyempty_
)
613 YYCDEBUG
<< "Reading a token: ";
614 yychar
= ]b4_c_function_call([yylex
], [int],
615 [[YYSTYPE
*], [&yylval
]][]dnl
616 b4_locations_if([, [[location
*], [&yylloc
]]])dnl
617 m4_ifdef([b4_lex_param
], [, ]b4_lex_param
))[;
621 /* Convert token to internal form. */
622 if (yychar
<= yyeof_
)
624 yychar
= yytoken
= yyeof_
;
625 YYCDEBUG
<< "Now at end of input." << std::endl
;
629 yytoken
= yytranslate_ (yychar
);
630 YY_SYMBOL_PRINT ("Next token is", yytoken
, &yylval
, &yylloc
);
633 /* If the proper action on seeing token YYTOKEN is to reduce or to
634 detect an error, take that action. */
636 if (yyn
< 0 || yylast_
< yyn
|| yycheck_
[yyn
] != yytoken
)
639 /* Reduce or error. */
643 if (yy_table_value_is_error_ (yyn
))
649 /* Shift the lookahead token. */
650 YY_SYMBOL_PRINT ("Shifting", yytoken
, &yylval
, &yylloc
);
652 /* Discard the token being shifted. */
655 yysemantic_stack_
.push (yylval
);
656 yylocation_stack_
.push (yylloc
);
658 /* Count tokens shifted since error; after three, turn off error
666 /*-----------------------------------------------------------.
667 | yydefault -- do the default action for the current state. |
668 `-----------------------------------------------------------*/
670 yyn
= yydefact_
[yystate
];
675 /*-----------------------------.
676 | yyreduce -- Do a reduction. |
677 `-----------------------------*/
680 /* If YYLEN is nonzero, implement the default value of the action:
681 `$$ = $1'. Otherwise, use the top of the stack.
683 Otherwise, the following line sets YYVAL to garbage.
684 This behavior is undocumented and Bison
685 users should not rely upon it. */
687 yyval
= yysemantic_stack_
[yylen
- 1];
689 yyval
= yysemantic_stack_
[0];
692 slice
<location_type
, location_stack_type
> slice (yylocation_stack_
, yylen
);
693 YYLLOC_DEFAULT (yyloc
, slice
, yylen
);
695 YY_REDUCE_PRINT (yyn
);
702 /* User semantic actions sometimes alter yychar, and that requires
703 that yytoken be updated with the new translation. We take the
704 approach of translating immediately before every use of yytoken.
705 One alternative is translating here after every semantic action,
706 but that translation would be missed if the semantic action
707 invokes YYABORT, YYACCEPT, or YYERROR immediately after altering
708 yychar. In the case of YYABORT or YYACCEPT, an incorrect
709 destructor might then be invoked immediately. In the case of
710 YYERROR, subsequent parser actions might lead to an incorrect
711 destructor call or verbose syntax error message before the
712 lookahead is translated. */
713 YY_SYMBOL_PRINT ("-> $$ =", yyr1_
[yyn
], &yyval
, &yyloc
);
719 yysemantic_stack_
.push (yyval
);
720 yylocation_stack_
.push (yyloc
);
722 /* Shift the result of the reduction. */
724 yystate
= yypgoto_
[yyn
- yyntokens_
] + yystate_stack_
[0];
725 if (0 <= yystate
&& yystate
<= yylast_
726 && yycheck_
[yystate
] == yystate_stack_
[0])
727 yystate
= yytable_
[yystate
];
729 yystate
= yydefgoto_
[yyn
- yyntokens_
];
732 /*------------------------------------.
733 | yyerrlab -- here on detecting error |
734 `------------------------------------*/
736 /* Make sure we have latest lookahead translation. See comments at
737 user semantic actions for why this is necessary. */
738 yytoken
= yytranslate_ (yychar
);
740 /* If not already recovering from an error, report this error. */
744 if (yychar
== yyempty_
)
746 error (yylloc
, yysyntax_error_ (yystate
, yytoken
));
749 yyerror_range
[1] = yylloc
;
750 if (yyerrstatus_
== 3)
752 /* If just tried and failed to reuse lookahead token after an
753 error, discard it. */
755 if (yychar
<= yyeof_
)
757 /* Return failure if at end of input. */
758 if (yychar
== yyeof_
)
763 yydestruct_ ("Error: discarding", yytoken
, &yylval
, &yylloc
);
768 /* Else will try to reuse lookahead token after shifting the error
773 /*---------------------------------------------------.
774 | yyerrorlab -- error raised explicitly by YYERROR. |
775 `---------------------------------------------------*/
778 /* Pacify compilers like GCC when the user code never invokes
779 YYERROR and the label yyerrorlab therefore never appears in user
784 yyerror_range
[1] = yylocation_stack_
[yylen
- 1];
785 /* Do not reclaim the symbols of the rule which action triggered
789 yystate
= yystate_stack_
[0];
792 /*-------------------------------------------------------------.
793 | yyerrlab1 -- common code for both syntax error and YYERROR. |
794 `-------------------------------------------------------------*/
796 yyerrstatus_
= 3; /* Each real token shifted decrements this. */
800 yyn
= yypact_
[yystate
];
801 if (!yy_pact_value_is_default_ (yyn
))
804 if (0 <= yyn
&& yyn
<= yylast_
&& yycheck_
[yyn
] == yyterror_
)
812 /* Pop the current state because it cannot handle the error token. */
813 if (yystate_stack_
.height () == 1)
816 yyerror_range
[1] = yylocation_stack_
[0];
817 yydestruct_ ("Error: popping",
819 &yysemantic_stack_
[0], &yylocation_stack_
[0]);
821 yystate
= yystate_stack_
[0];
825 yyerror_range
[2] = yylloc
;
826 // Using YYLLOC is tempting, but would change the location of
827 // the lookahead. YYLOC is available though.
828 YYLLOC_DEFAULT (yyloc
, yyerror_range
, 2);
829 yysemantic_stack_
.push (yylval
);
830 yylocation_stack_
.push (yyloc
);
832 /* Shift the error token. */
833 YY_SYMBOL_PRINT ("Shifting", yystos_
[yyn
],
834 &yysemantic_stack_
[0], &yylocation_stack_
[0]);
850 if (yychar
!= yyempty_
)
852 /* Make sure we have latest lookahead translation. See comments
853 at user semantic actions for why this is necessary. */
854 yytoken
= yytranslate_ (yychar
);
855 yydestruct_ ("Cleanup: discarding lookahead", yytoken
, &yylval
,
859 /* Do not reclaim the symbols of the rule which action triggered
860 this YYABORT or YYACCEPT. */
862 while (yystate_stack_
.height () != 1)
864 yydestruct_ ("Cleanup: popping",
865 yystos_
[yystate_stack_
[0]],
866 &yysemantic_stack_
[0],
867 &yylocation_stack_
[0]);
874 // Generate an error message.
876 ]b4_parser_class_name
[::yysyntax_error_ (]dnl
877 b4_error_verbose_if([int yystate
, int yytoken
],
879 {]b4_error_verbose_if([[
881 // Number of reported tokens (one for the "unexpected", one per
885 enum { YYERROR_VERBOSE_ARGS_MAXIMUM
= 5 };
886 // Arguments of yyformat.
887 char const *yyarg
[YYERROR_VERBOSE_ARGS_MAXIMUM
];
889 /* There are many possibilities here to consider:
890 - If this state is a consistent state with a default action, then
891 the only way this function was invoked is if the default action
892 is an error action. In that case, don't check for expected
893 tokens because there are none.
894 - The only way there can be no lookahead present (in yytoken) is
895 if this state is a consistent state with a default action.
896 Thus, detecting the absence of a lookahead is sufficient to
897 determine that there is no unexpected or expected token to
898 report. In that case, just report a simple "syntax error".
899 - Don't assume there isn't a lookahead just because this state is
900 a consistent state with a default action. There might have
901 been a previous inconsistent state, consistent state with a
902 non-default action, or user semantic action that manipulated
904 - Of course, the expected token list depends on states to have
905 correct lookahead information, and it depends on the parser not
906 to perform extra reductions after fetching a lookahead from the
907 scanner and before detecting a syntax error. Thus, state
908 merging (from LALR or IELR) and default reductions corrupt the
909 expected token list. However, the list is correct for
910 canonical LR with one exception: it will still contain any
911 token that will not be accepted due to an error action in a
914 if (yytoken
!= yyempty_
)
916 yyarg
[yycount
++] = yytname_
[yytoken
];
917 int yyn
= yypact_
[yystate
];
918 if (!yy_pact_value_is_default_ (yyn
))
920 /* Start YYX at -YYN if negative to avoid negative indexes in
921 YYCHECK. In other words, skip the first -YYN actions for
922 this state because they are default actions. */
923 int yyxbegin
= yyn
< 0 ? -yyn
: 0;
924 /* Stay within bounds of both yycheck and yytname. */
925 int yychecklim
= yylast_
- yyn
+ 1;
926 int yyxend
= yychecklim
< yyntokens_
? yychecklim
: yyntokens_
;
927 for (int yyx
= yyxbegin
; yyx
< yyxend
; ++yyx
)
928 if (yycheck_
[yyx
+ yyn
] == yyx
&& yyx
!= yyterror_
929 && !yy_table_value_is_error_ (yytable_
[yyx
+ yyn
]))
931 if (yycount
== YYERROR_VERBOSE_ARGS_MAXIMUM
)
937 yyarg
[yycount
++] = yytname_
[yyx
];
942 char const* yyformat
= YY_NULL
;
945 #define YYCASE_(N, S) \
949 YYCASE_(0, YY_("syntax error"));
950 YYCASE_(1, YY_("syntax error, unexpected %s"));
951 YYCASE_(2, YY_("syntax error, unexpected %s, expecting %s"));
952 YYCASE_(3, YY_("syntax error, unexpected %s, expecting %s or %s"));
953 YYCASE_(4, YY_("syntax error, unexpected %s, expecting %s or %s or %s"));
954 YYCASE_(5, YY_("syntax error, unexpected %s, expecting %s or %s or %s or %s"));
960 for (char const* yyp
= yyformat
; *yyp
; ++yyp
)
961 if (yyp
[0] == '%' && yyp
[1] == 's' && yyi
< yycount
)
963 yyres
+= yytnamerr_ (yyarg
[yyi
++]);
969 return YY_("syntax error");]])[
973 /* YYPACT[STATE-NUM] -- Index in YYTABLE of the portion describing
975 const ]b4_int_type(b4_pact_ninf
, b4_pact_ninf
) b4_parser_class_name::yypact_ninf_
= b4_pact_ninf
[;
976 const ]b4_int_type_for([b4_pact
])[
977 ]b4_parser_class_name
[::yypact_
[] =
982 /* YYDEFACT[S] -- default reduction number in state S. Performed when
983 YYTABLE doesn't specify something else to do. Zero means the
984 default is an error. */
985 const ]b4_int_type_for([b4_defact
])[
986 ]b4_parser_class_name
[::yydefact_
[] =
991 /* YYPGOTO[NTERM-NUM]. */
992 const ]b4_int_type_for([b4_pgoto
])[
993 ]b4_parser_class_name
[::yypgoto_
[] =
998 /* YYDEFGOTO[NTERM-NUM]. */
999 const ]b4_int_type_for([b4_defgoto
])[
1000 ]b4_parser_class_name
[::yydefgoto_
[] =
1005 /* YYTABLE[YYPACT[STATE-NUM]]. What to do in state STATE-NUM. If
1006 positive, shift that token. If negative, reduce the rule which
1007 number is the opposite. If YYTABLE_NINF_, syntax error. */
1008 const ]b4_int_type(b4_table_ninf
, b4_table_ninf
) b4_parser_class_name::yytable_ninf_
= b4_table_ninf
[;
1009 const ]b4_int_type_for([b4_table
])[
1010 ]b4_parser_class_name
[::yytable_
[] =
1016 const ]b4_int_type_for([b4_check
])[
1017 ]b4_parser_class_name
[::yycheck_
[] =
1022 /* STOS_[STATE-NUM] -- The (internal number of the) accessing
1023 symbol of state STATE-NUM. */
1024 const ]b4_int_type_for([b4_stos
])[
1025 ]b4_parser_class_name
[::yystos_
[] =
1031 /* TOKEN_NUMBER_[YYLEX-NUM] -- Internal symbol number corresponding
1033 const ]b4_int_type_for([b4_toknum
])[
1034 ]b4_parser_class_name
[::yytoken_number_
[] =
1040 /* YYR1[YYN] -- Symbol number of symbol that rule YYN derives. */
1041 const ]b4_int_type_for([b4_r1
])[
1042 ]b4_parser_class_name
[::yyr1_
[] =
1047 /* YYR2[YYN] -- Number of symbols composing right hand side of rule YYN. */
1048 const ]b4_int_type_for([b4_r2
])[
1049 ]b4_parser_class_name
[::yyr2_
[] =
1054 #if YYDEBUG || YYERROR_VERBOSE || YYTOKEN_TABLE
1055 /* YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
1056 First, the terminals, then, starting at \a yyntokens_, nonterminals. */
1058 const ]b4_parser_class_name
[::yytname_
[] =
1065 /* YYRHS -- A `-1'-separated list of the rules' RHS. */
1066 const ]b4_parser_class_name
[::rhs_number_type
1067 ]b4_parser_class_name
[::yyrhs_
[] =
1072 /* YYPRHS[YYN] -- Index of the first RHS symbol of rule number YYN in
1074 const ]b4_int_type_for([b4_prhs
])[
1075 ]b4_parser_class_name
[::yyprhs_
[] =
1080 /* YYRLINE[YYN] -- Source line where rule number YYN was defined. */
1081 const ]b4_int_type_for([b4_rline
])[
1082 ]b4_parser_class_name
[::yyrline_
[] =
1087 // Print the state stack on the debug stream.
1089 ]b4_parser_class_name
[::yystack_print_ ()
1091 *yycdebug_
<< "Stack now";
1092 for (state_stack_type::const_iterator i
= yystate_stack_
.begin ();
1093 i
!= yystate_stack_
.end (); ++i
)
1094 *yycdebug_
<< ' ' << *i
;
1095 *yycdebug_
<< std::endl
;
1098 // Report on the debug stream that the rule \a yyrule is going to be reduced.
1100 ]b4_parser_class_name
[::yy_reduce_print_ (int yyrule
)
1102 unsigned int yylno
= yyrline_
[yyrule
];
1103 int yynrhs
= yyr2_
[yyrule
];
1104 /* Print the symbols being reduced, and their result. */
1105 *yycdebug_
<< "Reducing stack by rule " << yyrule
- 1
1106 << " (line " << yylno
<< "):" << std::endl
;
1107 /* The symbols being reduced. */
1108 for (int yyi
= 0; yyi
< yynrhs
; yyi
++)
1109 YY_SYMBOL_PRINT (" $" << yyi
+ 1 << " =",
1110 yyrhs_
[yyprhs_
[yyrule
] + yyi
],
1111 &]b4_rhs_value(yynrhs
, yyi
+ 1)[,
1112 &]b4_rhs_location(yynrhs
, yyi
+ 1)[);
1116 /* YYTRANSLATE(YYLEX) -- Bison symbol number corresponding to YYLEX. */
1117 ]b4_parser_class_name
[::token_number_type
1118 ]b4_parser_class_name
[::yytranslate_ (int t
)
1121 const token_number_type
1126 if ((unsigned int) t
<= yyuser_token_number_max_
)
1127 return translate_table
[t
];
1129 return yyundef_token_
;
1132 const int ]b4_parser_class_name
[::yyeof_
= 0;
1133 const int ]b4_parser_class_name
[::yylast_
= ]b4_last
[;
1134 const int ]b4_parser_class_name
[::yynnts_
= ]b4_nterms_number
[;
1135 const int ]b4_parser_class_name
[::yyempty_
= -2;
1136 const int ]b4_parser_class_name
[::yyfinal_
= ]b4_final_state_number
[;
1137 const int ]b4_parser_class_name
[::yyterror_
= 1;
1138 const int ]b4_parser_class_name
[::yyerrcode_
= 256;
1139 const int ]b4_parser_class_name
[::yyntokens_
= ]b4_tokens_number
[;
1141 const unsigned int ]b4_parser_class_name
[::yyuser_token_number_max_
= ]b4_user_token_number_max
[;
1142 const ]b4_parser_class_name
[::token_number_type
]b4_parser_class_name
[::yyundef_token_
= ]b4_undef_token_number
[;
1144 ]b4_namespace_close
[