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"]])[
63 class ]b4_parser_class_name
[
66 /// Symbol semantic values.
67 #ifndef ]b4_api_PREFIX[STYPE
73 [m4_if(b4_tag_seen_flag
, 0,
74 [[ typedef int semantic_type
;]],
75 [[ typedef ]b4_api_PREFIX
[STYPE semantic_type
;]])])[
77 typedef ]b4_api_PREFIX
[STYPE semantic_type
;
80 typedef ]b4_percent_define_get([[location_type]],
81 [[location]])[ location_type
;
85 ]b4_token_enums(b4_tokens
)[
88 typedef token::yytokentype token_type
;
90 /// Build a parser object.
91 ]b4_parser_class_name
[ (]b4_parse_param_decl
[);
92 virtual ~]b4_parser_class_name
[ ();
95 /// \returns 0 iff parsing succeeded.
98 #if ]b4_api_PREFIX[DEBUG
99 /// The current debugging stream.
100 std::ostream
& debug_stream () const;
101 /// Set the current debugging stream.
102 void set_debug_stream (std::ostream
&);
104 /// Type for debugging levels.
105 typedef int debug_level_type
;
106 /// The current debugging level.
107 debug_level_type
debug_level () const;
108 /// Set the current debugging level.
109 void set_debug_level (debug_level_type l
);
113 /// Report a syntax error.
114 /// \param loc where the syntax error is found.
115 /// \param msg a description of the syntax error.
116 virtual void error (const location_type
& loc
, const std::string
& msg
);
118 /// Generate an error message.
119 /// \param state the state where the error occurred.
120 /// \param tok the lookahead token.
121 virtual std::string
yysyntax_error_ (int yystate
, int tok
);
123 #if ]b4_api_PREFIX[DEBUG
124 /// \brief Report a symbol value on the debug stream.
125 /// \param yytype The token type.
126 /// \param yyvaluep Its semantic value.
127 /// \param yylocationp Its location.
128 virtual void yy_symbol_value_print_ (int yytype
,
129 const semantic_type
* yyvaluep
,
130 const location_type
* yylocationp
);
131 /// \brief Report a symbol on the debug stream.
132 /// \param yytype The token type.
133 /// \param yyvaluep Its semantic value.
134 /// \param yylocationp Its location.
135 virtual void yy_symbol_print_ (int yytype
,
136 const semantic_type
* yyvaluep
,
137 const location_type
* yylocationp
);
142 typedef int state_type
;
143 /// State stack type.
144 typedef stack
<state_type
> state_stack_type
;
145 /// Semantic value stack type.
146 typedef stack
<semantic_type
> semantic_stack_type
;
147 /// location stack type.
148 typedef stack
<location_type
> location_stack_type
;
151 state_stack_type yystate_stack_
;
152 /// The semantic value stack.
153 semantic_stack_type yysemantic_stack_
;
154 /// The location stack.
155 location_stack_type yylocation_stack_
;
157 /// Whether the given \c yypact_ value indicates a defaulted state.
158 /// \param yyvalue the value to check
159 static bool yy_pact_value_is_default_ (int yyvalue
);
161 /// Whether the given \c yytable_ value indicates a syntax error.
162 /// \param yyvalue the value to check
163 static bool yy_table_value_is_error_ (int yyvalue
);
165 /// Internal symbol numbers.
166 typedef ]b4_int_type_for([b4_translate
])[ token_number_type
;
168 /// For a state, the index in \a yytable_ of its portion.
169 static const ]b4_int_type_for([b4_pact
])[ yypact_
[];
170 static const ]b4_int_type(b4_pact_ninf
, b4_pact_ninf
)[ yypact_ninf_
;
172 /// For a state, default reduction number.
173 /// Unless\a yytable_ specifies something else to do.
174 /// Zero means the default is an error.
175 static const ]b4_int_type_for([b4_defact
])[ yydefact_
[];
177 static const ]b4_int_type_for([b4_pgoto
])[ yypgoto_
[];
178 static const ]b4_int_type_for([b4_defgoto
])[ yydefgoto_
[];
180 /// What to do in a state.
181 /// \a yytable_[yypact_[s]]: what to do in state \a s.
182 /// - if positive, shift that token.
183 /// - if negative, reduce the rule which number is the opposite.
184 /// - if zero, do what YYDEFACT says.
185 static const ]b4_int_type_for([b4_table
])[ yytable_
[];
186 static const ]b4_int_type(b4_table_ninf
, b4_table_ninf
)[ yytable_ninf_
;
188 static const ]b4_int_type_for([b4_check
])[ yycheck_
[];
190 /// For a state, its accessing symbol.
191 static const ]b4_int_type_for([b4_stos
])[ yystos_
[];
193 /// For a rule, its LHS.
194 static const ]b4_int_type_for([b4_r1
])[ yyr1_
[];
195 /// For a rule, its RHS length.
196 static const ]b4_int_type_for([b4_r2
])[ yyr2_
[]; ]b4_error_verbose_if([
198 /// Convert the symbol name \a n to a form suitable for a diagnostic.
199 static std::string
yytnamerr_ (const char *n
);])[
201 ]b4_token_table_if([], [[#if ]b4_api_PREFIX[DEBUG]])[
202 /// For a symbol, its name in clear.
203 static const char* const yytname_
[];
204 ]b4_token_table_if([[#if ]b4_api_PREFIX[DEBUG]])[
205 /// A type to store symbol numbers and -1.
206 typedef ]b4_int_type_for([b4_rhs
])[ rhs_number_type
;
207 /// A `-1'-separated list of the rules' RHS.
208 static const rhs_number_type yyrhs_
[];
209 /// For each rule, the index of the first RHS symbol in \a yyrhs_.
210 static const ]b4_int_type_for([b4_prhs
])[ yyprhs_
[];
211 /// For each rule, its source line number.
212 static const ]b4_int_type_for([b4_rline
])[ yyrline_
[];
213 /// For each scanner token number, its symbol number.
214 static const ]b4_int_type_for([b4_toknum
])[ yytoken_number_
[];
215 /// Report on the debug stream that the rule \a r is going to be reduced.
216 virtual void yy_reduce_print_ (int r
);
217 /// Print the state stack on the debug stream.
218 virtual void yystack_print_ ();
222 std::ostream
* yycdebug_
;
225 /// Convert a scanner token number \a t to a symbol number.
226 token_number_type
yytranslate_ (int t
);
228 /// \brief Reclaim the memory associated to a symbol.
229 /// \param yymsg Why this token is reclaimed.
230 /// \param yytype The symbol type.
231 /// \param yyvaluep Its semantic value.
232 /// \param yylocationp Its location.
233 inline void yydestruct_ (const char* yymsg
,
235 semantic_type
* yyvaluep
,
236 location_type
* yylocationp
);
238 /// Pop \a n symbols the three stacks.
239 inline void yypop_ (unsigned int n
= 1);
242 static const int yyeof_
;
243 /* LAST_ -- Last index in TABLE_. */
244 static const int yylast_
;
245 static const int yynnts_
;
246 static const int yyempty_
;
247 static const int yyfinal_
;
248 static const int yyterror_
;
249 static const int yyerrcode_
;
250 static const int yyntokens_
;
251 static const unsigned int yyuser_token_number_max_
;
252 static const token_number_type yyundef_token_
;
253 ]b4_parse_param_vars
[
257 ]b4_percent_define_flag_if([[global_tokens_and_yystype]],
258 [b4_token_defines(b4_tokens
)
260 #ifndef ]b4_api_PREFIX[STYPE
261 /* Redirection for backward compatibility. */
262 # define ]b4_api_PREFIX[STYPE b4_namespace_ref::b4_parser_class_name::semantic_type
265 ]b4_percent_code_get([[provides]])[
266 ]b4_cpp_guard_close([b4_spec_defines_file
])
268 @
output(b4_parser_file_name@
)@
269 b4_copyright([Skeleton implementation
for Bison
LALR(1) parsers in C
++],
271 b4_percent_code_get([[top]])[]dnl
272 m4_if(b4_prefix
, [yy
], [],
274 // Take the name prefix into account.
275 #define yylex b4_prefix[]lex])[
277 /* First part of user declarations. */
278 ]b4_user_pre_prologue
[
281 #include "@basename(]b4_spec_defines_file[@)"]])[
283 /* User implementation prologue. */
284 ]b4_user_post_prologue
[
285 ]b4_percent_code_get
[
290 # if defined YYENABLE_NLS && YYENABLE_NLS
292 # include <libintl.h> /* FIXME: INFRINGES ON USER NAME SPACE */
293 # define YY_(msgid) dgettext ("bison-runtime", msgid)
297 # define YY_(msgid) msgid
301 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
302 If N is 0, then set CURRENT to the empty location which ends
303 the previous symbol: RHS[0] (always defined). */
305 #define YYRHSLOC(Rhs, K) ((Rhs)[K])
306 #ifndef YYLLOC_DEFAULT
307 # define YYLLOC_DEFAULT(Current, Rhs, N) \
311 (Current).begin = YYRHSLOC (Rhs, 1).begin; \
312 (Current).end = YYRHSLOC (Rhs, N).end; \
316 (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end; \
321 /* Suppress unused-variable warnings by "using" E. */
322 #define YYUSE(e) ((void) (e))
324 /* Enable debugging if requested. */
325 #if ]b4_api_PREFIX[DEBUG
327 /* A pseudo ostream that takes yydebug_ into account. */
328 # define YYCDEBUG if (yydebug_) (*yycdebug_)
330 # define YY_SYMBOL_PRINT(Title, Type, Value, Location) \
334 *yycdebug_ << Title << ' '; \
335 yy_symbol_print_ ((Type), (Value), (Location)); \
336 *yycdebug_ << std::endl; \
340 # define YY_REDUCE_PRINT(Rule) \
343 yy_reduce_print_ (Rule); \
346 # define YY_STACK_PRINT() \
352 #else /* !]b4_api_PREFIX[DEBUG */
354 # define YYCDEBUG if (false) std::cerr
355 # define YY_SYMBOL_PRINT(Title, Type, Value, Location)
356 # define YY_REDUCE_PRINT(Rule)
357 # define YY_STACK_PRINT()
359 #endif /* !]b4_api_PREFIX[DEBUG */
361 #define yyerrok (yyerrstatus_ = 0)
362 #define yyclearin (yychar = yyempty_)
364 #define YYACCEPT goto yyacceptlab
365 #define YYABORT goto yyabortlab
366 #define YYERROR goto yyerrorlab
367 #define YYRECOVERING() (!!yyerrstatus_)
369 ]b4_namespace_open
[]b4_error_verbose_if([[
371 /* Return YYSTR after stripping away unnecessary quotes and
372 backslashes, so that it's suitable for yyerror. The heuristic is
373 that double-quoting is unnecessary unless the string contains an
374 apostrophe, a comma, or backslash (other than backslash-backslash).
375 YYSTR is taken from yytname. */
377 ]b4_parser_class_name
[::yytnamerr_ (const char *yystr
)
381 std::string yyr
= "";
382 char const *yyp
= yystr
;
389 goto do_not_strip_quotes
;
393 goto do_not_strip_quotes
;
402 do_not_strip_quotes
: ;
409 /// Build a parser object.
410 ]b4_parser_class_name::b4_parser_class_name
[ (]b4_parse_param_decl
[)]m4_ifset([b4_parse_param
], [
412 #if ]b4_api_PREFIX[DEBUG
413 ]m4_ifset([b4_parse_param
], [ ], [ :])[yydebug_ (false),
414 yycdebug_ (&std::cerr
)]m4_ifset([b4_parse_param
], [,])[
415 #endif]b4_parse_param_cons[
419 ]b4_parser_class_name::~b4_parser_class_name
[ ()
423 #if ]b4_api_PREFIX[DEBUG
424 /*--------------------------------.
425 | Print this symbol on YYOUTPUT. |
426 `--------------------------------*/
429 ]b4_parser_class_name
[::yy_symbol_value_print_ (int yytype
,
430 const semantic_type
* yyvaluep
, const location_type
* yylocationp
)
434 std::ostream
& yyo
= debug_stream ();
435 std::ostream
& yyoutput
= yyo
;
439 ]m4_map([b4_symbol_actions
], m4_defn([b4_symbol_printers
]))dnl
447 ]b4_parser_class_name
[::yy_symbol_print_ (int yytype
,
448 const semantic_type
* yyvaluep
, const location_type
* yylocationp
)
450 *yycdebug_
<< (yytype
< yyntokens_
? "token" : "nterm")
451 << ' ' << yytname_
[yytype
] << " ("
452 << *yylocationp
<< ": ";
453 yy_symbol_value_print_ (yytype
, yyvaluep
, yylocationp
);
459 ]b4_parser_class_name
[::yydestruct_ (const char* yymsg
,
460 int yytype
, semantic_type
* yyvaluep
, location_type
* yylocationp
)
466 YY_SYMBOL_PRINT (yymsg
, yytype
, yyvaluep
, yylocationp
);
470 ]m4_map([b4_symbol_actions
], m4_defn([b4_symbol_destructors
]))[
477 ]b4_parser_class_name
[::yypop_ (unsigned int n
)
479 yystate_stack_
.pop (n
);
480 yysemantic_stack_
.pop (n
);
481 yylocation_stack_
.pop (n
);
484 #if ]b4_api_PREFIX[DEBUG
486 ]b4_parser_class_name
[::debug_stream () const
492 ]b4_parser_class_name
[::set_debug_stream (std::ostream
& o
)
498 ]b4_parser_class_name
[::debug_level_type
499 ]b4_parser_class_name
[::debug_level () const
505 ]b4_parser_class_name
[::set_debug_level (debug_level_type l
)
512 ]b4_parser_class_name
[::yy_pact_value_is_default_ (int yyvalue
)
514 return yyvalue
== yypact_ninf_
;
518 ]b4_parser_class_name
[::yy_table_value_is_error_ (int yyvalue
)
520 return yyvalue
== yytable_ninf_
;
524 ]b4_parser_class_name
[::parse ()
526 /// Lookahead and lookahead in internal form.
527 int yychar
= yyempty_
;
535 /* Error handling. */
537 int yyerrstatus_
= 0;
539 /// Semantic value of the lookahead.
540 semantic_type yylval
;
541 /// Location of the lookahead.
542 location_type yylloc
;
543 /// The locations where the error started and ended.
544 location_type yyerror_range
[3];
553 YYCDEBUG
<< "Starting parse" << std::endl
;
555 ]m4_ifdef([b4_initial_action
], [
556 m4_pushdef([b4_at_dollar
], [yylloc
])dnl
557 m4_pushdef([b4_dollar_dollar
], [yylval
])dnl
558 /* User initialization code. */
559 b4_user_initial_action
560 m4_popdef([b4_dollar_dollar
])dnl
561 m4_popdef([b4_at_dollar
])])dnl
563 [ /* Initialize the stacks. The initial state will be pushed in
564 yynewstate, since the latter expects the semantical and the
565 location values to have been already stored, initialize these
566 stacks with a primary value. */
567 yystate_stack_
= state_stack_type (0);
568 yysemantic_stack_
= semantic_stack_type (0);
569 yylocation_stack_
= location_stack_type (0);
570 yysemantic_stack_
.push (yylval
);
571 yylocation_stack_
.push (yylloc
);
575 yystate_stack_
.push (yystate
);
576 YYCDEBUG
<< "Entering state " << yystate
<< std::endl
;
579 if (yystate
== yyfinal_
)
587 /* Try to take a decision without lookahead. */
588 yyn
= yypact_
[yystate
];
589 if (yy_pact_value_is_default_ (yyn
))
592 /* Read a lookahead token. */
593 if (yychar
== yyempty_
)
595 YYCDEBUG
<< "Reading a token: ";
596 yychar
= ]b4_c_function_call([yylex
], [int],
597 [b4_api_PREFIX
[STYPE
*], [&yylval
]][]dnl
598 b4_locations_if([, [[location
*], [&yylloc
]]])dnl
599 m4_ifdef([b4_lex_param
], [, ]b4_lex_param
))[;
603 /* Convert token to internal form. */
604 if (yychar
<= yyeof_
)
606 yychar
= yytoken
= yyeof_
;
607 YYCDEBUG
<< "Now at end of input." << std::endl
;
611 yytoken
= yytranslate_ (yychar
);
612 YY_SYMBOL_PRINT ("Next token is", yytoken
, &yylval
, &yylloc
);
615 /* If the proper action on seeing token YYTOKEN is to reduce or to
616 detect an error, take that action. */
618 if (yyn
< 0 || yylast_
< yyn
|| yycheck_
[yyn
] != yytoken
)
621 /* Reduce or error. */
625 if (yy_table_value_is_error_ (yyn
))
631 /* Shift the lookahead token. */
632 YY_SYMBOL_PRINT ("Shifting", yytoken
, &yylval
, &yylloc
);
634 /* Discard the token being shifted. */
637 yysemantic_stack_
.push (yylval
);
638 yylocation_stack_
.push (yylloc
);
640 /* Count tokens shifted since error; after three, turn off error
648 /*-----------------------------------------------------------.
649 | yydefault -- do the default action for the current state. |
650 `-----------------------------------------------------------*/
652 yyn
= yydefact_
[yystate
];
657 /*-----------------------------.
658 | yyreduce -- Do a reduction. |
659 `-----------------------------*/
662 /* If YYLEN is nonzero, implement the default value of the action:
663 `$$ = $1'. Otherwise, use the top of the stack.
665 Otherwise, the following line sets YYVAL to garbage.
666 This behavior is undocumented and Bison
667 users should not rely upon it. */
669 yyval
= yysemantic_stack_
[yylen
- 1];
671 yyval
= yysemantic_stack_
[0];
674 slice
<location_type
, location_stack_type
> slice (yylocation_stack_
, yylen
);
675 YYLLOC_DEFAULT (yyloc
, slice
, yylen
);
677 YY_REDUCE_PRINT (yyn
);
684 /* User semantic actions sometimes alter yychar, and that requires
685 that yytoken be updated with the new translation. We take the
686 approach of translating immediately before every use of yytoken.
687 One alternative is translating here after every semantic action,
688 but that translation would be missed if the semantic action
689 invokes YYABORT, YYACCEPT, or YYERROR immediately after altering
690 yychar. In the case of YYABORT or YYACCEPT, an incorrect
691 destructor might then be invoked immediately. In the case of
692 YYERROR, subsequent parser actions might lead to an incorrect
693 destructor call or verbose syntax error message before the
694 lookahead is translated. */
695 YY_SYMBOL_PRINT ("-> $$ =", yyr1_
[yyn
], &yyval
, &yyloc
);
701 yysemantic_stack_
.push (yyval
);
702 yylocation_stack_
.push (yyloc
);
704 /* Shift the result of the reduction. */
706 yystate
= yypgoto_
[yyn
- yyntokens_
] + yystate_stack_
[0];
707 if (0 <= yystate
&& yystate
<= yylast_
708 && yycheck_
[yystate
] == yystate_stack_
[0])
709 yystate
= yytable_
[yystate
];
711 yystate
= yydefgoto_
[yyn
- yyntokens_
];
714 /*------------------------------------.
715 | yyerrlab -- here on detecting error |
716 `------------------------------------*/
718 /* Make sure we have latest lookahead translation. See comments at
719 user semantic actions for why this is necessary. */
720 yytoken
= yytranslate_ (yychar
);
722 /* If not already recovering from an error, report this error. */
726 if (yychar
== yyempty_
)
728 error (yylloc
, yysyntax_error_ (yystate
, yytoken
));
731 yyerror_range
[1] = yylloc
;
732 if (yyerrstatus_
== 3)
734 /* If just tried and failed to reuse lookahead token after an
735 error, discard it. */
737 if (yychar
<= yyeof_
)
739 /* Return failure if at end of input. */
740 if (yychar
== yyeof_
)
745 yydestruct_ ("Error: discarding", yytoken
, &yylval
, &yylloc
);
750 /* Else will try to reuse lookahead token after shifting the error
755 /*---------------------------------------------------.
756 | yyerrorlab -- error raised explicitly by YYERROR. |
757 `---------------------------------------------------*/
760 /* Pacify compilers like GCC when the user code never invokes
761 YYERROR and the label yyerrorlab therefore never appears in user
766 yyerror_range
[1] = yylocation_stack_
[yylen
- 1];
767 /* Do not reclaim the symbols of the rule which action triggered
771 yystate
= yystate_stack_
[0];
774 /*-------------------------------------------------------------.
775 | yyerrlab1 -- common code for both syntax error and YYERROR. |
776 `-------------------------------------------------------------*/
778 yyerrstatus_
= 3; /* Each real token shifted decrements this. */
782 yyn
= yypact_
[yystate
];
783 if (!yy_pact_value_is_default_ (yyn
))
786 if (0 <= yyn
&& yyn
<= yylast_
&& yycheck_
[yyn
] == yyterror_
)
794 /* Pop the current state because it cannot handle the error token. */
795 if (yystate_stack_
.height () == 1)
798 yyerror_range
[1] = yylocation_stack_
[0];
799 yydestruct_ ("Error: popping",
801 &yysemantic_stack_
[0], &yylocation_stack_
[0]);
803 yystate
= yystate_stack_
[0];
807 yyerror_range
[2] = yylloc
;
808 // Using YYLLOC is tempting, but would change the location of
809 // the lookahead. YYLOC is available though.
810 YYLLOC_DEFAULT (yyloc
, yyerror_range
, 2);
811 yysemantic_stack_
.push (yylval
);
812 yylocation_stack_
.push (yyloc
);
814 /* Shift the error token. */
815 YY_SYMBOL_PRINT ("Shifting", yystos_
[yyn
],
816 &yysemantic_stack_
[0], &yylocation_stack_
[0]);
832 if (yychar
!= yyempty_
)
834 /* Make sure we have latest lookahead translation. See comments
835 at user semantic actions for why this is necessary. */
836 yytoken
= yytranslate_ (yychar
);
837 yydestruct_ ("Cleanup: discarding lookahead", yytoken
, &yylval
,
841 /* Do not reclaim the symbols of the rule which action triggered
842 this YYABORT or YYACCEPT. */
844 while (yystate_stack_
.height () != 1)
846 yydestruct_ ("Cleanup: popping",
847 yystos_
[yystate_stack_
[0]],
848 &yysemantic_stack_
[0],
849 &yylocation_stack_
[0]);
856 // Generate an error message.
858 ]b4_parser_class_name
[::yysyntax_error_ (]dnl
859 b4_error_verbose_if([int yystate
, int yytoken
],
861 {]b4_error_verbose_if([[
863 // Number of reported tokens (one for the "unexpected", one per
867 enum { YYERROR_VERBOSE_ARGS_MAXIMUM
= 5 };
868 // Arguments of yyformat.
869 char const *yyarg
[YYERROR_VERBOSE_ARGS_MAXIMUM
];
871 /* There are many possibilities here to consider:
872 - If this state is a consistent state with a default action, then
873 the only way this function was invoked is if the default action
874 is an error action. In that case, don't check for expected
875 tokens because there are none.
876 - The only way there can be no lookahead present (in yytoken) is
877 if this state is a consistent state with a default action.
878 Thus, detecting the absence of a lookahead is sufficient to
879 determine that there is no unexpected or expected token to
880 report. In that case, just report a simple "syntax error".
881 - Don't assume there isn't a lookahead just because this state is
882 a consistent state with a default action. There might have
883 been a previous inconsistent state, consistent state with a
884 non-default action, or user semantic action that manipulated
886 - Of course, the expected token list depends on states to have
887 correct lookahead information, and it depends on the parser not
888 to perform extra reductions after fetching a lookahead from the
889 scanner and before detecting a syntax error. Thus, state
890 merging (from LALR or IELR) and default reductions corrupt the
891 expected token list. However, the list is correct for
892 canonical LR with one exception: it will still contain any
893 token that will not be accepted due to an error action in a
896 if (yytoken
!= yyempty_
)
898 yyarg
[yycount
++] = yytname_
[yytoken
];
899 int yyn
= yypact_
[yystate
];
900 if (!yy_pact_value_is_default_ (yyn
))
902 /* Start YYX at -YYN if negative to avoid negative indexes in
903 YYCHECK. In other words, skip the first -YYN actions for
904 this state because they are default actions. */
905 int yyxbegin
= yyn
< 0 ? -yyn
: 0;
906 /* Stay within bounds of both yycheck and yytname. */
907 int yychecklim
= yylast_
- yyn
+ 1;
908 int yyxend
= yychecklim
< yyntokens_
? yychecklim
: yyntokens_
;
909 for (int yyx
= yyxbegin
; yyx
< yyxend
; ++yyx
)
910 if (yycheck_
[yyx
+ yyn
] == yyx
&& yyx
!= yyterror_
911 && !yy_table_value_is_error_ (yytable_
[yyx
+ yyn
]))
913 if (yycount
== YYERROR_VERBOSE_ARGS_MAXIMUM
)
919 yyarg
[yycount
++] = yytname_
[yyx
];
924 char const* yyformat
= YY_NULL
;
927 #define YYCASE_(N, S) \
931 YYCASE_(0, YY_("syntax error"));
932 YYCASE_(1, YY_("syntax error, unexpected %s"));
933 YYCASE_(2, YY_("syntax error, unexpected %s, expecting %s"));
934 YYCASE_(3, YY_("syntax error, unexpected %s, expecting %s or %s"));
935 YYCASE_(4, YY_("syntax error, unexpected %s, expecting %s or %s or %s"));
936 YYCASE_(5, YY_("syntax error, unexpected %s, expecting %s or %s or %s or %s"));
942 for (char const* yyp
= yyformat
; *yyp
; ++yyp
)
943 if (yyp
[0] == '%' && yyp
[1] == 's' && yyi
< yycount
)
945 yyres
+= yytnamerr_ (yyarg
[yyi
++]);
951 return YY_("syntax error");]])[
955 /* YYPACT[STATE-NUM] -- Index in YYTABLE of the portion describing
957 const ]b4_int_type(b4_pact_ninf
, b4_pact_ninf
) b4_parser_class_name::yypact_ninf_
= b4_pact_ninf
[;
958 const ]b4_int_type_for([b4_pact
])[
959 ]b4_parser_class_name
[::yypact_
[] =
964 /* YYDEFACT[S] -- default reduction number in state S. Performed when
965 YYTABLE doesn't specify something else to do. Zero means the
966 default is an error. */
967 const ]b4_int_type_for([b4_defact
])[
968 ]b4_parser_class_name
[::yydefact_
[] =
973 /* YYPGOTO[NTERM-NUM]. */
974 const ]b4_int_type_for([b4_pgoto
])[
975 ]b4_parser_class_name
[::yypgoto_
[] =
980 /* YYDEFGOTO[NTERM-NUM]. */
981 const ]b4_int_type_for([b4_defgoto
])[
982 ]b4_parser_class_name
[::yydefgoto_
[] =
987 /* YYTABLE[YYPACT[STATE-NUM]]. What to do in state STATE-NUM. If
988 positive, shift that token. If negative, reduce the rule which
989 number is the opposite. If YYTABLE_NINF_, syntax error. */
990 const ]b4_int_type(b4_table_ninf
, b4_table_ninf
) b4_parser_class_name::yytable_ninf_
= b4_table_ninf
[;
991 const ]b4_int_type_for([b4_table
])[
992 ]b4_parser_class_name
[::yytable_
[] =
998 const ]b4_int_type_for([b4_check
])[
999 ]b4_parser_class_name
[::yycheck_
[] =
1004 /* STOS_[STATE-NUM] -- The (internal number of the) accessing
1005 symbol of state STATE-NUM. */
1006 const ]b4_int_type_for([b4_stos
])[
1007 ]b4_parser_class_name
[::yystos_
[] =
1012 #if ]b4_api_PREFIX[DEBUG
1013 /* TOKEN_NUMBER_[YYLEX-NUM] -- Internal symbol number corresponding
1015 const ]b4_int_type_for([b4_toknum
])[
1016 ]b4_parser_class_name
[::yytoken_number_
[] =
1022 /* YYR1[YYN] -- Symbol number of symbol that rule YYN derives. */
1023 const ]b4_int_type_for([b4_r1
])[
1024 ]b4_parser_class_name
[::yyr1_
[] =
1029 /* YYR2[YYN] -- Number of symbols composing right hand side of rule YYN. */
1030 const ]b4_int_type_for([b4_r2
])[
1031 ]b4_parser_class_name
[::yyr2_
[] =
1036 ]b4_token_table_if([], [[#if ]b4_api_PREFIX[DEBUG]])[
1037 /* YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
1038 First, the terminals, then, starting at \a yyntokens_, nonterminals. */
1040 const ]b4_parser_class_name
[::yytname_
[] =
1045 ]b4_token_table_if([[#if ]b4_api_PREFIX[DEBUG]])[
1046 /* YYRHS -- A `-1'-separated list of the rules' RHS. */
1047 const ]b4_parser_class_name
[::rhs_number_type
1048 ]b4_parser_class_name
[::yyrhs_
[] =
1053 /* YYPRHS[YYN] -- Index of the first RHS symbol of rule number YYN in
1055 const ]b4_int_type_for([b4_prhs
])[
1056 ]b4_parser_class_name
[::yyprhs_
[] =
1061 /* YYRLINE[YYN] -- Source line where rule number YYN was defined. */
1062 const ]b4_int_type_for([b4_rline
])[
1063 ]b4_parser_class_name
[::yyrline_
[] =
1068 // Print the state stack on the debug stream.
1070 ]b4_parser_class_name
[::yystack_print_ ()
1072 *yycdebug_
<< "Stack now";
1073 for (state_stack_type::const_iterator i
= yystate_stack_
.begin ();
1074 i
!= yystate_stack_
.end (); ++i
)
1075 *yycdebug_
<< ' ' << *i
;
1076 *yycdebug_
<< std::endl
;
1079 // Report on the debug stream that the rule \a yyrule is going to be reduced.
1081 ]b4_parser_class_name
[::yy_reduce_print_ (int yyrule
)
1083 unsigned int yylno
= yyrline_
[yyrule
];
1084 int yynrhs
= yyr2_
[yyrule
];
1085 /* Print the symbols being reduced, and their result. */
1086 *yycdebug_
<< "Reducing stack by rule " << yyrule
- 1
1087 << " (line " << yylno
<< "):" << std::endl
;
1088 /* The symbols being reduced. */
1089 for (int yyi
= 0; yyi
< yynrhs
; yyi
++)
1090 YY_SYMBOL_PRINT (" $" << yyi
+ 1 << " =",
1091 yyrhs_
[yyprhs_
[yyrule
] + yyi
],
1092 &]b4_rhs_value(yynrhs
, yyi
+ 1)[,
1093 &]b4_rhs_location(yynrhs
, yyi
+ 1)[);
1095 #endif // ]b4_api_PREFIX[DEBUG
1097 /* YYTRANSLATE(YYLEX) -- Bison symbol number corresponding to YYLEX. */
1098 ]b4_parser_class_name
[::token_number_type
1099 ]b4_parser_class_name
[::yytranslate_ (int t
)
1102 const token_number_type
1107 if ((unsigned int) t
<= yyuser_token_number_max_
)
1108 return translate_table
[t
];
1110 return yyundef_token_
;
1113 const int ]b4_parser_class_name
[::yyeof_
= 0;
1114 const int ]b4_parser_class_name
[::yylast_
= ]b4_last
[;
1115 const int ]b4_parser_class_name
[::yynnts_
= ]b4_nterms_number
[;
1116 const int ]b4_parser_class_name
[::yyempty_
= -2;
1117 const int ]b4_parser_class_name
[::yyfinal_
= ]b4_final_state_number
[;
1118 const int ]b4_parser_class_name
[::yyterror_
= 1;
1119 const int ]b4_parser_class_name
[::yyerrcode_
= 256;
1120 const int ]b4_parser_class_name
[::yyntokens_
= ]b4_tokens_number
[;
1122 const unsigned int ]b4_parser_class_name
[::yyuser_token_number_max_
= ]b4_user_token_number_max
[;
1123 const ]b4_parser_class_name
[::token_number_type
]b4_parser_class_name
[::yyundef_token_
= ]b4_undef_token_number
[;
1125 ]b4_namespace_close
[