xref: /aosp_15_r20/external/angle/tools/flex-bison/third_party/skeletons/lalr1.cc (revision 8975f5c5ed3d1c378011245431ada316dfb6f244)
1 #C++ skeleton for Bison
2 
3 #Copyright(C) 2002 - 2015, 2018 - 2021 Free Software Foundation, Inc.
4 
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.
9 #
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.
14 #
15 #You should have received a copy of the GNU General Public License
16 #along with this program.If not, see < https:  // www.gnu.org/licenses/>.
17 
18 m4_include(b4_skeletonsdir/[c++.m4])
19 
20 #api.value.type = variant is valid.
21 m4_define([b4_value_type_setup_variant])
22 
23 #parse.lac
24 b4_percent_define_default([[parse.lac]], [[none]])
25 b4_percent_define_check_values([[[[parse.lac]], [[full]], [[none]]]])
26 b4_define_flag_if([lac])
27 m4_define([b4_lac_flag],
28           [m4_if(b4_percent_define_get([[parse.lac]]),
29                  [none], [[0]], [[1]])])
30 
31 #b4_tname_if(TNAME - NEEDED, TNAME - NOT - NEEDED)
32 #-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -
33 m4_define([b4_tname_if],
34 [m4_case(b4_percent_define_get([[parse.error]]),
35          [verbose],         [$1],
36          [b4_token_table_if([$1],
37                             [$2])])])
38 
39 #b4_integral_parser_table_declare(TABLE - NAME, CONTENT, COMMENT)
40 #-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
41 #Declare "parser::yy<TABLE-NAME>_" whose contents is CONTENT.
42 m4_define([b4_integral_parser_table_declare],
43 [m4_ifval([$3], [b4_comment([$3], [    ])
44 ])dnl
45     static const b4_int_type_for([$2]) yy$1_[[]];dnl
46 ])
47 
48 #b4_integral_parser_table_define(TABLE - NAME, CONTENT, COMMENT)
49 #-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -
50 #Define "parser::yy<TABLE-NAME>_" whose contents is CONTENT.
51 m4_define([b4_integral_parser_table_define],
52 [  const b4_int_type_for([$2])
53   b4_parser_class::yy$1_[[]] =
54   {
55   $2
56   };dnl
57 ])
58 
59 #b4_symbol_kind(NUM)
60 #-- -- -- -- -- -- -- -- -- -
61 m4_define([b4_symbol_kind],
62 [symbol_kind::b4_symbol_kind_base($@)])
63 
64 #b4_symbol_value_template(VAL, SYMBOL - NUM, [TYPE])
65 #-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -
66 #Same as b4_symbol_value, but used in a template method.It makes
67 #a difference when using variants.Note that b4_value_type_setup_union
68 #overrides b4_symbol_value, so we must override it again.
69 m4_copy([b4_symbol_value], [b4_symbol_value_template])
70 m4_append([b4_value_type_setup_union],
71 [m4_copy_force([b4_symbol_value_union], [b4_symbol_value_template])])
72 
73 #b4_lhs_value(SYMBOL - NUM, [TYPE])
74 #-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
75 #See README.
76 m4_define([b4_lhs_value],
77 [b4_symbol_value([yylhs.value], [$1], [$2])])
78 
79 #b4_lhs_location()
80 #-- -- -- -- -- -- -- -- -
81 #Expansion of @$.
82 m4_define([b4_lhs_location],
83 [yylhs.location])
84 
85 #b4_rhs_data(RULE - LENGTH, POS)
86 #-- -- -- -- -- -- -- -- -- -- -- -- -- -- -
87 #See README.
88 m4_define([b4_rhs_data],
89 [yystack_@{b4_subtract($@)@}])
90 
91 #b4_rhs_state(RULE - LENGTH, POS)
92 #-- -- -- -- -- -- -- -- -- -- -- -- -- -- --
93 #The state corresponding to the symbol #POS, where the current
94 #rule has RULE - LENGTH symbols on RHS.
95 m4_define([b4_rhs_state],
96 [b4_rhs_data([$1], [$2]).state])
97 
98 #b4_rhs_value(RULE - LENGTH, POS, SYMBOL - NUM, [TYPE])
99 #-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
100 #See README.
101 m4_define([_b4_rhs_value],
102 [b4_symbol_value([b4_rhs_data([$1], [$2]).value], [$3], [$4])])
103 
104 m4_define([b4_rhs_value],
105 [b4_percent_define_ifdef([api.value.automove],
106                          [YY_MOVE (_b4_rhs_value($@))],
107                          [_b4_rhs_value($@)])])
108 
109 #b4_rhs_location(RULE - LENGTH, POS)
110 #-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -
111 #Expansion of @POS, where the current rule has RULE - LENGTH symbols
112 #on RHS.
113 m4_define([b4_rhs_location],
114 [b4_rhs_data([$1], [$2]).location])
115 
116 #b4_symbol_action(SYMBOL - NUM, KIND)
117 #-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
118 #Run the action KIND(destructor or printer) for SYMBOL - NUM.
119 #Same as in C, but using references instead of pointers.
120 m4_define([b4_symbol_action],
121 [b4_symbol_if([$1], [has_$2],
122 [m4_pushdef([b4_symbol_value], m4_defn([b4_symbol_value_template]))[]dnl
123 b4_dollar_pushdef([yysym.value],
124                   [$1],
125                   [],
126                   [yysym.location])dnl
127       _b4_symbol_case([$1])[]dnl
128 b4_syncline([b4_symbol([$1], [$2_line])], [b4_symbol([$1], [$2_file])])dnl
129         b4_symbol([$1], [$2])
130 b4_syncline([@oline@], [@ofile@])dnl
131         break;
132 
133 m4_popdef([b4_symbol_value])[]dnl
134 b4_dollar_popdef[]dnl
135 ])])
136 
137 #b4_yylex
138 #-- -- -- --
139 #Call yylex.
140 m4_define([b4_yylex],
141 [b4_token_ctor_if(
142 [b4_function_call([yylex],
143                   [symbol_type], m4_ifdef([b4_lex_param], b4_lex_param))],
144 [b4_function_call([yylex], [int],
145                   [[value_type *], [&yyla.value]][]dnl
146 b4_locations_if([, [[location_type *], [&yyla.location]]])dnl
147 m4_ifdef([b4_lex_param], [, ]b4_lex_param))])])
148 
149 
150 m4_pushdef([b4_copyright_years],
151            [2002-2015, 2018-2021])
152 
153 m4_define([b4_parser_class],
154           [b4_percent_define_get([[api.parser.class]])])
155 
156 b4_bison_locations_if([# Backward compatibility.
157    m4_define([b4_location_constructors])
158    m4_include(b4_skeletonsdir/[location.cc])])
159 m4_include(b4_skeletonsdir/[stack.hh])
160 b4_variant_if([m4_include(b4_skeletonsdir/[variant.hh])])
161 
162 #b4_shared_declarations(hh | cc)
163 #-- -- -- -- -- -- -- -- -- -- -- -- -- -- -
164 #Declaration that might either go into the header(if --header, $1 = hh)
165 # or in the implementation file.
166 m4_define([b4_shared_declarations],
167 [b4_percent_code_get([[requires]])[
168 ]b4_parse_assert_if([# include <cassert>])[
169 #include <cstdlib>  // std::abort
170 #include <iostream>
171 #include <stdexcept>
172 #include <string>
173 #include <vector>
174 
175 ]b4_cxx_portability[
176 ]m4_ifdef([b4_location_include],
177           [[# include ]b4_location_include])[
178 ]b4_variant_if([b4_variant_includes])[
179 
180 ]b4_attribute_define[
181 ]b4_cast_define[
182 ]b4_null_define[
183 
184 ]b4_YYDEBUG_define[
185 
186 ]b4_namespace_open[
187 
188 ]b4_bison_locations_if([m4_ifndef([b4_location_file],
189                                   [b4_location_define])])[
190 
191   /// A Bison parser.
192   class ]b4_parser_class[
193   {
194   public:
195 ]b4_public_types_declare[
196 ]b4_symbol_type_define[
197     /// Build a parser object.
198     ]b4_parser_class[ (]b4_parse_param_decl[);
199     virtual ~]b4_parser_class[ ();
200 
201 #if 201103L <= YY_CPLUSPLUS
202     /// Non copyable.
203     ]b4_parser_class[ (const ]b4_parser_class[&) = delete;
204     /// Non copyable.
205     ]b4_parser_class[& operator= (const ]b4_parser_class[&) = delete;
206 #endif
207 
208     /// Parse.  An alias for parse ().
209     /// \returns  0 iff parsing succeeded.
210     int operator() ();
211 
212     /// Parse.
213     /// \returns  0 iff parsing succeeded.
214     virtual int parse ();
215 
216 #if] b4_api_PREFIX[DEBUG
217     /// The current debugging stream.
218     std::ostream& debug_stream () const YY_ATTRIBUTE_PURE;
219     /// Set the current debugging stream.
220     void set_debug_stream (std::ostream &);
221 
222     /// Type for debugging levels.
223     typedef int debug_level_type;
224     /// The current debugging level.
225     debug_level_type debug_level () const YY_ATTRIBUTE_PURE;
226     /// Set the current debugging level.
227     void set_debug_level (debug_level_type l);
228 #endif
229 
230     /// Report a syntax error.]b4_locations_if([[
231     /// \param loc    where the syntax error is found.]])[
232     /// \param msg    a description of the syntax error.
233     virtual void error (]b4_locations_if([[const location_type& loc, ]])[const std::string& msg);
234 
235     /// Report a syntax error.
236     void error (const syntax_error& err);
237 
238 ]b4_parse_error_bmatch(
239 [custom\|detailed],
240 [[    /// The user-facing name of the symbol whose (internal) number is
241     /// YYSYMBOL.  No bounds checking.
242     static const char *symbol_name (symbol_kind_type yysymbol);]],
243 [simple],
244 [[#if ]b4_api_PREFIX[DEBUG || ]b4_token_table_flag[
245     /// The user-facing name of the symbol whose (internal) number is
246     /// YYSYMBOL.  No bounds checking.
247     static const char *symbol_name (symbol_kind_type yysymbol);
248 #endif  // #if ]b4_api_PREFIX[DEBUG || ]b4_token_table_flag[
249 ]],
250 [verbose],
251 [[    /// The user-facing name of the symbol whose (internal) number is
252     /// YYSYMBOL.  No bounds checking.
253     static std::string symbol_name (symbol_kind_type yysymbol);]])[
254 
255 ]b4_token_constructor_define[
256 ]b4_parse_error_bmatch([custom\|detailed\|verbose], [[
257     class context
258     {
259       public:
260       context (const ]b4_parser_class[& yyparser, const symbol_type& yyla);
261       const symbol_type &lookahead() const YY_NOEXCEPT
262       {
263           return yyla_;
264       }
265       symbol_kind_type token() const YY_NOEXCEPT
266       {
267           return yyla_.kind();
268       }]b4_locations_if([[
269       const location_type& location () const YY_NOEXCEPT {
270             return yyla_.location; }
271 ]])[
272       /// Put in YYARG at most YYARGN of the expected tokens, and return the
273       /// number of tokens stored in YYARG.  If YYARG is null, return the
274       /// number of expected tokens (guaranteed to be less than YYNTOKENS).
275       int expected_tokens (symbol_kind_type yyarg[], int yyargn) const;
276 
277     private:
278       const ]b4_parser_class[& yyparser_;
279       const symbol_type& yyla_;
280     };
281 ]])[
282   private:
283 #if YY_CPLUSPLUS < 201103L
284     /// Non copyable.
285     ]b4_parser_class[ (const ]b4_parser_class[&);
286     /// Non copyable.
287     ]b4_parser_class[& operator= (const ]b4_parser_class[&);
288 #endif
289 ]b4_lac_if([[
290     /// Check the lookahead yytoken.
291     /// \returns  true iff the token will be eventually shifted.
292     bool yy_lac_check_ (symbol_kind_type yytoken) const;
293     /// Establish the initial context if no initial context currently exists.
294     /// \returns  true iff the token will be eventually shifted.
295     bool yy_lac_establish_ (symbol_kind_type yytoken);
296     /// Discard any previous initial lookahead context because of event.
297     /// \param event  the event which caused the lookahead to be discarded.
298     ///               Only used for debbuging output.
299     void yy_lac_discard_ (const char* event);]])[
300 
301     /// Stored state numbers (used for stacks).
302     typedef ]b4_int_type(0, m4_eval(b4_states_number - 1))[ state_type;
303 ]b4_parse_error_bmatch(
304 [custom], [[
305     /// Report a syntax error
306     /// \param yyctx     the context in which the error occurred.
307     void report_syntax_error (const context& yyctx) const;]],
308 [detailed\|verbose], [[
309     /// The arguments of the error message.
310     int yy_syntax_error_arguments_ (const context& yyctx,
311                                     symbol_kind_type yyarg[], int yyargn) const;
312 
313     /// Generate an error message.
314     /// \param yyctx     the context in which the error occurred.
315     virtual std::string yysyntax_error_ (const context& yyctx) const;]])[
316     /// Compute post-reduction state.
317     /// \param yystate   the current state
318     /// \param yysym     the nonterminal to push on the stack
319     static state_type yy_lr_goto_state_ (state_type yystate, int yysym);
320 
321     /// Whether the given \c yypact_ value indicates a defaulted state.
322     /// \param yyvalue   the value to check
323     static bool yy_pact_value_is_default_ (int yyvalue) YY_NOEXCEPT;
324 
325     /// Whether the given \c yytable_ value indicates a syntax error.
326     /// \param yyvalue   the value to check
327     static bool yy_table_value_is_error_ (int yyvalue) YY_NOEXCEPT;
328 
329     static const ]b4_int_type(b4_pact_ninf, b4_pact_ninf)[ yypact_ninf_;
330     static const ]b4_int_type(b4_table_ninf, b4_table_ninf)[ yytable_ninf_;
331 
332     /// Convert a scanner token kind \a t to a symbol kind.
333     /// In theory \a t should be a token_kind_type, but character literals
334     /// are valid, yet not members of the token_kind_type enum.
335     static symbol_kind_type yytranslate_ (int t) YY_NOEXCEPT;
336 
337 ]b4_parse_error_bmatch(
338 [simple],
339 [[#if ]b4_api_PREFIX[DEBUG || ]b4_token_table_flag[
340     /// For a symbol, its name in clear.
341     static const char* const yytname_[];
342 #endif  // #if ]b4_api_PREFIX[DEBUG || ]b4_token_table_flag[
343 ]],
344 [verbose],
345 [[    /// Convert the symbol name \a n to a form suitable for a diagnostic.
346     static std::string yytnamerr_ (const char *yystr);
347 
348     /// For a symbol, its name in clear.
349     static const char* const yytname_[];
350 ]])[
351 
352     // Tables.
353 ]b4_parser_tables_declare[
354 
355 #if] b4_api_PREFIX[DEBUG
356 ]b4_integral_parser_table_declare([rline], [b4_rline],
357      [[YYRLINE[YYN] -- Source line where rule number YYN was defined.]])[
358     /// Report on the debug stream that the rule \a r is going to be reduced.
359     virtual void yy_reduce_print_ (int r) const;
360     /// Print the state stack on the debug stream.
361     virtual void yy_stack_print_ () const;
362 
363     /// Debugging level.
364     int yydebug_;
365     /// Debug stream.
366     std::ostream* yycdebug_;
367 
368     /// \brief Display a symbol kind, value and location.
369     /// \param yyo    The output stream.
370     /// \param yysym  The symbol.
371     template <typename Base>
372     void yy_print_ (std::ostream& yyo, const basic_symbol<Base>& yysym) const;
373 #endif
374 
375     /// \brief Reclaim the memory associated to a symbol.
376     /// \param yymsg     Why this token is reclaimed.
377     ///                  If null, print nothing.
378     /// \param yysym     The symbol.
379     template <typename Base>
380     void yy_destroy_ (const char* yymsg, basic_symbol<Base>& yysym) const;
381 
382   private:
383     /// Type access provider for state based symbols.
384     struct by_state
385     {
386         /// Default constructor.
387         by_state() YY_NOEXCEPT;
388 
389         /// The symbol kind as needed by the constructor.
390         typedef state_type kind_type;
391 
392         /// Constructor.
393         by_state(kind_type s) YY_NOEXCEPT;
394 
395         /// Copy constructor.
396         by_state(const by_state &that) YY_NOEXCEPT;
397 
398         /// Record that this symbol is empty.
399         void clear() YY_NOEXCEPT;
400 
401         /// Steal the symbol kind from \a that.
402         void move(by_state & that);
403 
404         /// The symbol kind (corresponding to \a state).
405         /// \a ]b4_symbol(empty, kind)[ when empty.
406         symbol_kind_type kind() const YY_NOEXCEPT;
407 
408         /// The state number used to denote an empty symbol.
409         /// We use the initial state, as it does not have a value.
410         enum
411         {
412             empty_state = 0
413         };
414 
415         /// The state.
416         /// \a empty when empty.
417         state_type state;
418     };
419 
420     /// "Internal" symbol: element of the stack.
421     struct stack_symbol_type : basic_symbol<by_state>
422     {
423         /// Superclass.
424         typedef basic_symbol<by_state> super_type;
425         /// Construct an empty symbol.
426         stack_symbol_type();
427         /// Move or copy construction.
428         stack_symbol_type(YY_RVREF(stack_symbol_type) that);
429         /// Steal the contents from \a sym to build this.
430         stack_symbol_type(state_type s, YY_MOVE_REF(symbol_type) sym);
431 #if YY_CPLUSPLUS < 201103L
432         /// Assignment, needed by push_back by some old implementations.
433         /// Moves the contents of that.
434         stack_symbol_type &operator=(stack_symbol_type &that);
435 
436         /// Assignment, needed by push_back by other implementations.
437         /// Needed by some other old implementations.
438         stack_symbol_type &operator=(const stack_symbol_type &that);
439 #endif
440     };
441 
442 ]b4_stack_define[
443 
444     /// Stack type.
445     typedef stack<stack_symbol_type> stack_type;
446 
447     /// The stack.
448     stack_type yystack_;]b4_lac_if([[
449     /// The stack for LAC.
450     /// Logically, the yy_lac_stack's lifetime is confined to the function
451     /// yy_lac_check_. We just store it as a member of this class to hold
452     /// on to the memory and to avoid frequent reallocations.
453     /// Since yy_lac_check_ is const, this member must be mutable.
454     mutable std::vector<state_type> yylac_stack_;
455     /// Whether an initial LAC context was established.
456     bool yy_lac_established_;
457 ]])[
458 
459     /// Push a new state on the stack.
460     /// \param m    a debug message to display
461     ///             if null, no trace is output.
462     /// \param sym  the symbol
463     /// \warning the contents of \a s.value is stolen.
464     void yypush_ (const char* m, YY_MOVE_REF (stack_symbol_type) sym);
465 
466     /// Push a new look ahead token on the state on the stack.
467     /// \param m    a debug message to display
468     ///             if null, no trace is output.
469     /// \param s    the state
470     /// \param sym  the symbol (for its value and location).
471     /// \warning the contents of \a sym.value is stolen.
472     void yypush_ (const char* m, state_type s, YY_MOVE_REF (symbol_type) sym);
473 
474     /// Pop \a n symbols from the stack.
475     void yypop_ (int n = 1) YY_NOEXCEPT;
476 
477     /// Constants.
478     enum
479     {
480       yylast_ = ]b4_last[,     ///< Last index in yytable_.
481       yynnts_ = ]b4_nterms_number[,  ///< Number of nonterminal symbols.
482       yyfinal_ = ]b4_final_state_number[ ///< Termination state number.
483     };
484 
485 ]b4_parse_param_vars[
486 ]b4_percent_code_get([[yy_bison_internal_hook]])[
487   };
488 
489 ]b4_token_ctor_if([b4_yytranslate_define([$1])[
490 ]b4_public_types_define([$1])])[
491 ]b4_namespace_close[
492 
493 ]b4_percent_code_get([[provides]])[
494 ]])[
495 
496 
497 ## -------------- ##
498 ## Output files.  ##
499 ## -------------- ##
500 
501 #-- -- -- -- -- -- - #
502 #Header file.#
503 #-- -- -- -- -- -- - #
504 
505 ]b4_header_if([[
506 ]b4_output_begin([b4_spec_header_file])[
507 ]b4_copyright([Skeleton interface for Bison LALR(1) parsers in C++])[
508 
509 /**
510  ** \file ]b4_spec_mapped_header_file[
511  ** Define the ]b4_namespace_ref[::parser class.
512  */
513 
514 // C++ LALR(1) parser skeleton written by Akim Demaille.
515 
516 ]b4_disclaimer[
517 ]b4_cpp_guard_open([b4_spec_mapped_header_file])[
518 ]b4_shared_declarations(hh)[
519 ]b4_cpp_guard_close([b4_spec_mapped_header_file])[
520 ]b4_output_end[
521 ]])[
522 
523 #-- -- -- -- -- -- -- -- -- -- - #
524 #Implementation file.#
525 #-- -- -- -- -- -- -- -- -- -- - #
526 
527 ]b4_output_begin([b4_parser_file_name])[
528 ]b4_copyright([Skeleton implementation for Bison LALR(1) parsers in C++])[
529 ]b4_disclaimer[
530 ]b4_percent_code_get([[top]])[]dnl
531 m4_if(b4_prefix, [yy], [],
532 [
533 // Take the name prefix into account.
534 [#]define yylex   b4_prefix[]lex])[
535 
536 ]b4_user_pre_prologue[
537 
538 ]b4_header_if([[#include "@basename(]b4_spec_header_file[@)"]],
539                [b4_shared_declarations([cc])])[
540 
541 ]b4_user_post_prologue[
542 ]b4_percent_code_get[
543 
544 #ifndef YY_
545 #    if defined YYENABLE_NLS && YYENABLE_NLS
546 #        if ENABLE_NLS
547 #            include <libintl.h>  // FIXME: INFRINGES ON USER NAME SPACE.
548 #            define YY_(msgid) dgettext("bison-runtime", msgid)
549 #        endif
550 #    endif
551 #    ifndef YY_
552 #        define YY_(msgid) msgid
553 #    endif
554 #endif
555 ]b4_has_translations_if([
556 #ifndef N_
557 #    define N_(Msgid) Msgid
558 #endif
559 ])[
560 
561 // Whether we are compiled with exception support.
562 #ifndef YY_EXCEPTIONS
563 #    if defined __GNUC__ && !defined __EXCEPTIONS
564 #        define YY_EXCEPTIONS 0
565 #    else
566 #        define YY_EXCEPTIONS 1
567 #    endif
568 #endif
569 
570 ]b4_locations_if([dnl
571 [#define YYRHSLOC(Rhs, K) ((Rhs)[K].location)
572 ]b4_yylloc_default_define])[
573 
574 // Enable debugging if requested.
575 #if] b4_api_PREFIX[DEBUG
576 
577 // A pseudo ostream that takes yydebug_ into account.
578 #    define YYCDEBUG  \
579         if (yydebug_) \
580         (*yycdebug_)
581 
582 #    define YY_SYMBOL_PRINT(Title, Symbol)     \
583         do                                     \
584         {                                      \
585             if (yydebug_)                      \
586             {                                  \
587                 *yycdebug_ << Title << ' ';    \
588                 yy_print_(*yycdebug_, Symbol); \
589                 *yycdebug_ << '\n';            \
590             }                                  \
591         } while (false)
592 
593 #    define YY_REDUCE_PRINT(Rule)       \
594         do                              \
595         {                               \
596             if (yydebug_)               \
597                 yy_reduce_print_(Rule); \
598         } while (false)
599 
600 #    define YY_STACK_PRINT()       \
601         do                         \
602         {                          \
603             if (yydebug_)          \
604                 yy_stack_print_(); \
605         } while (false)
606 
607 #else  // !]b4_api_PREFIX[DEBUG
608 
609 #    define YYCDEBUG \
610         if (false)   \
611         std::cerr
612 #    define YY_SYMBOL_PRINT(Title, Symbol) YY_USE(Symbol)
613 #    define YY_REDUCE_PRINT(Rule) static_cast<void>(0)
614 #    define YY_STACK_PRINT() static_cast<void>(0)
615 
616 #endif  // !]b4_api_PREFIX[DEBUG
617 
618 #define yyerrok (yyerrstatus_ = 0)
619 #define yyclearin (yyla.clear())
620 
621 #define YYACCEPT goto yyacceptlab
622 #define YYABORT goto yyabortlab
623 #define YYERROR goto yyerrorlab
624 #define YYRECOVERING() (!!yyerrstatus_)
625 
626 ]b4_namespace_open[
627   /// Build a parser object.
628   ]b4_parser_class::b4_parser_class[ (]b4_parse_param_decl[)
629 #if] b4_api_PREFIX[DEBUG
630     : yydebug_ (false),
631       yycdebug_ (&std::cerr)]b4_lac_if([,], [m4_ifset([b4_parse_param], [,])])[
632 #else
633 ]b4_lac_if([    :], [m4_ifset([b4_parse_param], [    :])])[
634 #endif] b4_lac_if([[
635       yy_lac_established_ (false)]m4_ifset([b4_parse_param], [,])])[]b4_parse_param_cons[
636   {}
637 
638   ]b4_parser_class::~b4_parser_class[ ()
639   {}
640 
641   ]b4_parser_class[::syntax_error::~syntax_error () YY_NOEXCEPT YY_NOTHROW
642   {}
643 
644   /*---------.
645   | symbol.  |
646   `---------*/
647 
648 ]b4_token_ctor_if([], [b4_public_types_define([cc])])[
649 
650   // by_state.
651   ]b4_parser_class[::by_state::by_state () YY_NOEXCEPT
652     : state (empty_state)
653   {}
654 
655   ]b4_parser_class[::by_state::by_state (const by_state& that) YY_NOEXCEPT
656     : state (that.state)
657   {}
658 
659   void
660   ]b4_parser_class[::by_state::clear () YY_NOEXCEPT
661   {
662     state = empty_state;
663   }
664 
665   void
666   ]b4_parser_class[::by_state::move (by_state& that)
667   {
668     state = that.state;
669     that.clear();
670   }
671 
672   ]b4_parser_class[::by_state::by_state (state_type s) YY_NOEXCEPT
673     : state (s)
674   {}
675 
676   ]b4_parser_class[::symbol_kind_type
677   ]b4_parser_class[::by_state::kind () const YY_NOEXCEPT
678   {
679     if (state == empty_state)
680       return ]b4_symbol(empty, kind)[;
681     else
682       return YY_CAST (symbol_kind_type, yystos_[+state]);
683   }
684 
685   ]b4_parser_class[::stack_symbol_type::stack_symbol_type ()
686   {}
687 
688   ]b4_parser_class[::stack_symbol_type::stack_symbol_type (YY_RVREF (stack_symbol_type) that)
689     : super_type (YY_MOVE (that.state)]b4_variant_if([], [, YY_MOVE (that.value)])b4_locations_if([, YY_MOVE (that.location)])[)
690   {]b4_variant_if([
691     b4_symbol_variant([that.kind ()],
692                       [value], [YY_MOVE_OR_COPY], [YY_MOVE (that.value)])])[
693 #if 201103L <= YY_CPLUSPLUS
694     // that is emptied.
695     that.state = empty_state;
696 #endif
697   }
698 
699   ]b4_parser_class[::stack_symbol_type::stack_symbol_type (state_type s, YY_MOVE_REF (symbol_type) that)
700     : super_type (s]b4_variant_if([], [, YY_MOVE (that.value)])[]b4_locations_if([, YY_MOVE (that.location)])[)
701   {]b4_variant_if([
702     b4_symbol_variant([that.kind ()],
703                       [value], [move], [YY_MOVE (that.value)])])[
704     // that is emptied.
705     that.kind_ = ]b4_symbol(empty, kind)[;
706   }
707 
708 #if YY_CPLUSPLUS < 201103L
709   ]b4_parser_class[::stack_symbol_type&
710   ]b4_parser_class[::stack_symbol_type::operator= (const stack_symbol_type& that)
711   {
712     state = that.state;
713     ]b4_variant_if([b4_symbol_variant([that.kind ()],
714                                       [value], [copy], [that.value])],
715                    [[value = that.value;]])[]b4_locations_if([
716     location = that.location;])[
717     return *this;
718   }
719 
720   ]b4_parser_class[::stack_symbol_type&
721   ]b4_parser_class[::stack_symbol_type::operator= (stack_symbol_type& that)
722   {
723     state = that.state;
724     ]b4_variant_if([b4_symbol_variant([that.kind ()],
725                                       [value], [move], [that.value])],
726                    [[value = that.value;]])[]b4_locations_if([
727     location = that.location;])[
728     // that is emptied.
729     that.state = empty_state;
730     return *this;
731   }
732 #endif
733 
734   template <typename Base>
735   void
736   ]b4_parser_class[::yy_destroy_ (const char* yymsg, basic_symbol<Base>& yysym) const
737   {
738     if (yymsg)
739         YY_SYMBOL_PRINT(yymsg, yysym);]b4_variant_if([], [
740 
741     // User destructor.
742     b4_symbol_actions([destructor], [yysym.kind ()])])[
743   }
744 
745 #if] b4_api_PREFIX[DEBUG
746   template <typename Base>
747   void
748   ]b4_parser_class[::yy_print_ (std::ostream& yyo, const basic_symbol<Base>& yysym) const
749   {
750     std::ostream &yyoutput = yyo;
751     YY_USE(yyoutput);
752     if (yysym.empty())
753         yyo << "empty symbol";
754     else
755     {
756         symbol_kind_type yykind = yysym.kind();
757         yyo << (yykind < YYNTOKENS ? "token" : "nterm")
758             << ' ' << yysym.name () << " ("]b4_locations_if([
759             << yysym.location << ": "])[;
760         ]b4_symbol_actions([printer])[
761         yyo << ')';
762     }
763   }
764 #endif
765 
766   void
767   ]b4_parser_class[::yypush_ (const char* m, YY_MOVE_REF (stack_symbol_type) sym)
768   {
769     if (m)
770         YY_SYMBOL_PRINT(m, sym);
771     yystack_.push(YY_MOVE(sym));
772   }
773 
774   void
775   ]b4_parser_class[::yypush_ (const char* m, state_type s, YY_MOVE_REF (symbol_type) sym)
776   {
777 #if 201103L <= YY_CPLUSPLUS
778     yypush_(m, stack_symbol_type(s, std::move(sym)));
779 #else
780     stack_symbol_type ss(s, sym);
781     yypush_(m, ss);
782 #endif
783   }
784 
785   void
786   ]b4_parser_class[::yypop_ (int n) YY_NOEXCEPT
787   {
788     yystack_.pop(n);
789   }
790 
791 #if] b4_api_PREFIX[DEBUG
792   std::ostream&
793   ]b4_parser_class[::debug_stream () const
794   {
795     return *yycdebug_;
796   }
797 
798   void
799   ]b4_parser_class[::set_debug_stream (std::ostream& o)
800   {
801     yycdebug_ = &o;
802   }
803 
804 
805   ]b4_parser_class[::debug_level_type
806   ]b4_parser_class[::debug_level () const
807   {
808     return yydebug_;
809   }
810 
811   void
812   ]b4_parser_class[::set_debug_level (debug_level_type l)
813   {
814     yydebug_ = l;
815   }
816 #endif  // ]b4_api_PREFIX[DEBUG
817 
818   ]b4_parser_class[::state_type
819   ]b4_parser_class[::yy_lr_goto_state_ (state_type yystate, int yysym)
820   {
821     int yyr = yypgoto_[yysym - YYNTOKENS] + yystate;
822     if (0 <= yyr && yyr <= yylast_ && yycheck_[yyr] == yystate)
823         return yytable_[yyr];
824     else
825         return yydefgoto_[yysym - YYNTOKENS];
826   }
827 
828   bool
829   ]b4_parser_class[::yy_pact_value_is_default_ (int yyvalue) YY_NOEXCEPT
830   {
831     return yyvalue == yypact_ninf_;
832   }
833 
834   bool
835   ]b4_parser_class[::yy_table_value_is_error_ (int yyvalue) YY_NOEXCEPT
836   {
837     return yyvalue == yytable_ninf_;
838   }
839 
840   int
841   ]b4_parser_class[::operator() ()
842   {
843     return parse();
844   }
845 
846   int
847   ]b4_parser_class[::parse ()
848   {
849     int yyn;
850     /// Length of the RHS of the rule being reduced.
851     int yylen = 0;
852 
853     // Error handling.
854     int yynerrs_     = 0;
855     int yyerrstatus_ = 0;
856 
857     /// The lookahead symbol.
858     symbol_type yyla;]b4_locations_if([[
859 
860     /// The locations where the error started and ended.
861     stack_symbol_type yyerror_range[3];]])[
862 
863     /// The return value of parse ().
864     int yyresult;]b4_lac_if([[
865 
866     // Discard the LAC context in case there still is one left from a
867     // previous invocation.
868     yy_lac_discard_ ("init");]])[
869 
870 #if YY_EXCEPTIONS
871     try
872 #endif  // YY_EXCEPTIONS
873       {
874         YYCDEBUG << "Starting parse\n";
875 
876 ]m4_ifdef([b4_initial_action], [
877 b4_dollar_pushdef([yyla.value], [], [], [yyla.location])dnl
878     b4_user_initial_action
879 b4_dollar_popdef])[]dnl
880 
881   [  /* Initialize the stack.  The initial state will be set in
882        yynewstate, since the latter expects the semantical and the
883        location values to have been already stored, initialize these
884        stacks with a primary value.  */
885     yystack_.clear ();
886     yypush_ (YY_NULLPTR, 0, YY_MOVE (yyla));
887 
888   /*-----------------------------------------------.
889   | yynewstate -- push a new symbol on the stack.  |
890   `-----------------------------------------------*/
891   yynewstate:
892     YYCDEBUG << "Entering state " << int (yystack_[0].state) << '\n';
893     YY_STACK_PRINT ();
894 
895     // Accept?
896     if (yystack_[0].state == yyfinal_)
897       YYACCEPT;
898 
899     goto yybackup;
900 
901 
902   /*-----------.
903   | yybackup.  |
904   `-----------*/
905   yybackup:
906     // Try to take a decision without lookahead.
907     yyn = yypact_[+yystack_[0].state];
908     if (yy_pact_value_is_default_ (yyn))
909       goto yydefault;
910 
911     // Read a lookahead token.
912     if (yyla.empty ())
913       {
914             YYCDEBUG << "Reading a token\n";
915 #if YY_EXCEPTIONS
916             try
917 #endif  // YY_EXCEPTIONS
918             {]b4_token_ctor_if([[
919             symbol_type yylookahead (]b4_yylex[);
920             yyla.move (yylookahead);]], [[
921             yyla.kind_ = yytranslate_ (]b4_yylex[);]])[
922             }
923 #if YY_EXCEPTIONS
924             catch (const syntax_error &yyexc)
925             {
926                 YYCDEBUG << "Caught exception: " << yyexc.what() << '\n';
927                 error(yyexc);
928                 goto yyerrlab1;
929             }
930 #endif  // YY_EXCEPTIONS
931       }
932     YY_SYMBOL_PRINT ("Next token is", yyla);
933 
934     if (yyla.kind () == ]b4_symbol(error, kind)[)
935     {
936             // The scanner already issued an error message, process directly
937             // to error recovery.  But do not keep the error token as
938             // lookahead, it is too special and may lead us to an endless
939             // loop in error recovery. */
940       yyla.kind_ = ]b4_symbol(undef, kind)[;
941       goto yyerrlab1;
942     }
943 
944     /* If the proper action on seeing token YYLA.TYPE is to reduce or
945        to detect an error, take that action.  */
946     yyn += yyla.kind ();
947     if (yyn < 0 || yylast_ < yyn || yycheck_[yyn] != yyla.kind ())
948       {]b4_lac_if([[
949         if (!yy_lac_establish_ (yyla.kind ()))
950           goto yyerrlab;]])[
951         goto yydefault;
952       }
953 
954     // Reduce or error.
955     yyn = yytable_[yyn];
956     if (yyn <= 0)
957       {
958             if (yy_table_value_is_error_(yyn))
959                 goto yyerrlab;]b4_lac_if([[
960         if (!yy_lac_establish_ (yyla.kind ()))
961           goto yyerrlab;
962 ]])[
963         yyn = -yyn;
964         goto yyreduce;
965       }
966 
967     // Count tokens shifted since error; after three, turn off error status.
968     if (yyerrstatus_)
969       --yyerrstatus_;
970 
971     // Shift the lookahead token.
972     yypush_ ("Shifting", state_type (yyn), YY_MOVE (yyla));]b4_lac_if([[
973     yy_lac_discard_ ("shift");]])[
974     goto yynewstate;
975 
976 
977   /*-----------------------------------------------------------.
978   | yydefault -- do the default action for the current state.  |
979   `-----------------------------------------------------------*/
980   yydefault:
981     yyn = yydefact_[+yystack_[0].state];
982     if (yyn == 0)
983       goto yyerrlab;
984     goto yyreduce;
985 
986 
987   /*-----------------------------.
988   | yyreduce -- do a reduction.  |
989   `-----------------------------*/
990   yyreduce:
991     yylen = yyr2_[yyn];
992     {
993             stack_symbol_type yylhs;
994             yylhs.state = yy_lr_goto_state_(yystack_[yylen].state, yyr1_[yyn]);]b4_variant_if([[
995       /* Variants are always initialized to an empty instance of the
996          correct type. The default '$$ = $1' action is NOT applied
997          when using variants.  */
998       ]b4_symbol_variant([[yyr1_@{yyn@}]], [yylhs.value], [emplace])], [[
999       /* If YYLEN is nonzero, implement the default value of the
1000          action: '$$ = $1'.  Otherwise, use the top of the stack.
1001 
1002          Otherwise, the following line sets YYLHS.VALUE to garbage.
1003          This behavior is undocumented and Bison users should not rely
1004          upon it.  */
1005       if (yylen)
1006         yylhs.value = yystack_@{yylen - 1@}.value;
1007       else
1008         yylhs.value = yystack_@{0@}.value;]])[
1009 ]b4_locations_if([dnl
1010 [
1011       // Default location.
1012       {
1013                 stack_type::slice range(yystack_, yylen);
1014                 YYLLOC_DEFAULT(yylhs.location, range, yylen);
1015                 yyerror_range[1].location = yylhs.location;
1016       }]])[
1017 
1018       // Perform the reduction.
1019       YY_REDUCE_PRINT (yyn);
1020 #if YY_EXCEPTIONS
1021       try
1022 #endif  // YY_EXCEPTIONS
1023         {
1024                 switch (yyn)
1025                 {
1026 ]b4_user_actions[
1027             default:
1028               break;
1029                 }
1030         }
1031 #if YY_EXCEPTIONS
1032       catch (const syntax_error& yyexc)
1033         {
1034                 YYCDEBUG << "Caught exception: " << yyexc.what() << '\n';
1035                 error(yyexc);
1036                 YYERROR;
1037         }
1038 #endif  // YY_EXCEPTIONS
1039       YY_SYMBOL_PRINT ("-> $$ =", yylhs);
1040       yypop_ (yylen);
1041       yylen = 0;
1042 
1043       // Shift the result of the reduction.
1044       yypush_ (YY_NULLPTR, YY_MOVE (yylhs));
1045     }
1046     goto yynewstate;
1047 
1048 
1049   /*--------------------------------------.
1050   | yyerrlab -- here on detecting error.  |
1051   `--------------------------------------*/
1052   yyerrlab:
1053     // If not already recovering from an error, report this error.
1054     if (!yyerrstatus_)
1055       {
1056             ++yynerrs_;]b4_parse_error_case(
1057                   [simple], [[
1058         std::string msg = YY_("syntax error");
1059         error (]b4_join(b4_locations_if([yyla.location]), [[YY_MOVE (msg)]])[);]],
1060                   [custom], [[
1061         context yyctx (*this, yyla);
1062         report_syntax_error (yyctx);]],
1063                   [[
1064         context yyctx (*this, yyla);
1065         std::string msg = yysyntax_error_ (yyctx);
1066         error (]b4_join(b4_locations_if([yyla.location]), [[YY_MOVE (msg)]])[);]])[
1067       }
1068 
1069 ]b4_locations_if([[
1070     yyerror_range[1].location = yyla.location;]])[
1071     if (yyerrstatus_ == 3)
1072       {
1073             /* If just tried and failed to reuse lookahead token after an
1074                error, discard it.  */
1075 
1076             // Return failure if at end of input.
1077         if (yyla.kind () == ]b4_symbol(eof, kind)[)
1078             YYABORT;
1079         else if (!yyla.empty())
1080         {
1081             yy_destroy_("Error: discarding", yyla);
1082             yyla.clear();
1083         }
1084       }
1085 
1086     // Else will try to reuse lookahead token after shifting the error token.
1087     goto yyerrlab1;
1088 
1089 
1090   /*---------------------------------------------------.
1091   | yyerrorlab -- error raised explicitly by YYERROR.  |
1092   `---------------------------------------------------*/
1093   yyerrorlab:
1094     /* Pacify compilers when the user code never invokes YYERROR and
1095        the label yyerrorlab therefore never appears in user code.  */
1096     if (false)
1097       YYERROR;
1098 
1099     /* Do not reclaim the symbols of the rule whose action triggered
1100        this YYERROR.  */
1101     yypop_ (yylen);
1102     yylen = 0;
1103     YY_STACK_PRINT ();
1104     goto yyerrlab1;
1105 
1106 
1107   /*-------------------------------------------------------------.
1108   | yyerrlab1 -- common code for both syntax error and YYERROR.  |
1109   `-------------------------------------------------------------*/
1110   yyerrlab1:
1111     yyerrstatus_ = 3;   // Each real token shifted decrements this.
1112     // Pop stack until we find a state that shifts the error token.
1113     for (;;)
1114       {
1115             yyn = yypact_[+yystack_[0].state];
1116             if (!yy_pact_value_is_default_(yyn))
1117             {
1118             yyn += ]b4_symbol(error, kind)[;
1119             if (0 <= yyn && yyn <= yylast_
1120                 && yycheck_[yyn] == ]b4_symbol(error, kind)[)
1121               {
1122                     yyn = yytable_[yyn];
1123                     if (0 < yyn)
1124                         break;
1125               }
1126             }
1127 
1128             // Pop the current state because it cannot handle the error token.
1129             if (yystack_.size() == 1)
1130                 YYABORT;
1131 ]b4_locations_if([[
1132         yyerror_range[1].location = yystack_[0].location;]])[
1133         yy_destroy_ ("Error: popping", yystack_[0]);
1134         yypop_ ();
1135         YY_STACK_PRINT ();
1136       }
1137     {
1138             stack_symbol_type error_token;
1139 ]b4_locations_if([[
1140       yyerror_range[2].location = yyla.location;
1141       YYLLOC_DEFAULT (error_token.location, yyerror_range, 2);]])[
1142 
1143       // Shift the error token.]b4_lac_if([[
1144       yy_lac_discard_ ("error recovery");]])[
1145       error_token.state = state_type (yyn);
1146       yypush_ ("Shifting", YY_MOVE (error_token));
1147     }
1148     goto yynewstate;
1149 
1150 
1151   /*-------------------------------------.
1152   | yyacceptlab -- YYACCEPT comes here.  |
1153   `-------------------------------------*/
1154   yyacceptlab:
1155     yyresult = 0;
1156     goto yyreturn;
1157 
1158 
1159   /*-----------------------------------.
1160   | yyabortlab -- YYABORT comes here.  |
1161   `-----------------------------------*/
1162   yyabortlab:
1163     yyresult = 1;
1164     goto yyreturn;
1165 
1166 
1167   /*-----------------------------------------------------.
1168   | yyreturn -- parsing is finished, return the result.  |
1169   `-----------------------------------------------------*/
1170   yyreturn:
1171     if (!yyla.empty ())
1172       yy_destroy_ ("Cleanup: discarding lookahead", yyla);
1173 
1174     /* Do not reclaim the symbols of the rule whose action triggered
1175        this YYABORT or YYACCEPT.  */
1176     yypop_ (yylen);
1177     YY_STACK_PRINT ();
1178     while (1 < yystack_.size ())
1179       {
1180             yy_destroy_("Cleanup: popping", yystack_[0]);
1181             yypop_();
1182       }
1183 
1184     return yyresult;
1185   }
1186 #if YY_EXCEPTIONS
1187     catch (...)
1188       {
1189         YYCDEBUG << "Exception caught: cleaning lookahead and stack\n";
1190         // Do not try to display the values of the reclaimed symbols,
1191         // as their printers might throw an exception.
1192         if (!yyla.empty())
1193             yy_destroy_(YY_NULLPTR, yyla);
1194 
1195         while (1 < yystack_.size())
1196         {
1197             yy_destroy_(YY_NULLPTR, yystack_[0]);
1198             yypop_();
1199         }
1200         throw;
1201       }
1202 #endif  // YY_EXCEPTIONS
1203   }
1204 
1205   void
1206   ]b4_parser_class[::error (const syntax_error& yyexc)
1207   {
1208     error (]b4_join(b4_locations_if([yyexc.location]),
1209                     [[yyexc.what ()]])[);
1210   }
1211 
1212 ]b4_parse_error_bmatch([custom\|detailed],
1213 [[  const char *
1214   ]b4_parser_class[::symbol_name (symbol_kind_type yysymbol)
1215   {
1216     static const char *const yy_sname[] =
1217     {
1218     ]b4_symbol_names[
1219     };]b4_has_translations_if([[
1220     /* YYTRANSLATABLE[SYMBOL-NUM] -- Whether YY_SNAME[SYMBOL-NUM] is
1221        internationalizable.  */
1222     static ]b4_int_type_for([b4_translatable])[ yytranslatable[] =
1223     {
1224     ]b4_translatable[
1225     };
1226     return (yysymbol < YYNTOKENS && yytranslatable[yysymbol]
1227             ? _(yy_sname[yysymbol])
1228             : yy_sname[yysymbol]);]], [[
1229     return yy_sname[yysymbol];]])[
1230   }
1231 ]],
1232 [simple],
1233 [[#if ]b4_api_PREFIX[DEBUG || ]b4_token_table_flag[
1234   const char *
1235   ]b4_parser_class[::symbol_name (symbol_kind_type yysymbol)
1236   {
1237     return yytname_[yysymbol];
1238   }
1239 #endif  // #if ]b4_api_PREFIX[DEBUG || ]b4_token_table_flag[
1240 ]],
1241 [verbose],
1242 [[  /* Return YYSTR after stripping away unnecessary quotes and
1243      backslashes, so that it's suitable for yyerror.  The heuristic is
1244      that double-quoting is unnecessary unless the string contains an
1245      apostrophe, a comma, or backslash (other than backslash-backslash).
1246      YYSTR is taken from yytname.  */
1247   std::string
1248   ]b4_parser_class[::yytnamerr_ (const char *yystr)
1249   {
1250     if (*yystr == '"')
1251     {
1252         std::string yyr;
1253         char const *yyp = yystr;
1254 
1255         for (;;)
1256             switch (*++yyp)
1257             {
1258                 case '\'':
1259                 case ',':
1260                     goto do_not_strip_quotes;
1261 
1262                 case '\\':
1263                     if (*++yyp != '\\')
1264                         goto do_not_strip_quotes;
1265                     else
1266                         goto append;
1267 
1268                 append:
1269                 default:
1270                     yyr += *yyp;
1271                     break;
1272 
1273                 case '"':
1274                     return yyr;
1275             }
1276     do_not_strip_quotes:;
1277     }
1278 
1279     return yystr;
1280   }
1281 
1282   std::string
1283   ]b4_parser_class[::symbol_name (symbol_kind_type yysymbol)
1284   {
1285     return yytnamerr_(yytname_[yysymbol]);
1286   }
1287 ]])[
1288 
1289 ]b4_parse_error_bmatch([custom\|detailed\|verbose], [[
1290   // ]b4_parser_class[::context.
1291   ]b4_parser_class[::context::context (const ]b4_parser_class[& yyparser, const symbol_type& yyla)
1292     : yyparser_ (yyparser)
1293     , yyla_ (yyla)
1294   {}
1295 
1296   int
1297   ]b4_parser_class[::context::expected_tokens (symbol_kind_type yyarg[], int yyargn) const
1298   {
1299     // Actual number of expected tokens
1300     int yycount = 0;
1301 ]b4_lac_if([[
1302 #if] b4_api_PREFIX[DEBUG
1303     // Execute LAC once. We don't care if it is successful, we
1304     // only do it for the sake of debugging output.
1305     if (!yyparser_.yy_lac_established_)
1306       yyparser_.yy_lac_check_ (yyla_.kind ());
1307 #endif
1308 
1309     for (int yyx = 0; yyx < YYNTOKENS; ++yyx)
1310       {
1311         symbol_kind_type yysym = YY_CAST(symbol_kind_type, yyx);
1312         if (yysym != ]b4_symbol(error, kind)[
1313             && yysym != ]b4_symbol(undef, kind)[
1314             && yyparser_.yy_lac_check_ (yysym))
1315         {
1316             if (!yyarg)
1317                 ++yycount;
1318             else if (yycount == yyargn)
1319                 return 0;
1320             else
1321                 yyarg[yycount++] = yysym;
1322         }
1323       }]], [[
1324     const int yyn = yypact_[+yyparser_.yystack_[0].state];
1325     if (!yy_pact_value_is_default_ (yyn))
1326       {
1327         /* Start YYX at -YYN if negative to avoid negative indexes in
1328            YYCHECK.  In other words, skip the first -YYN actions for
1329            this state because they are default actions.  */
1330         const int yyxbegin = yyn < 0 ? -yyn : 0;
1331         // Stay within bounds of both yycheck and yytname.
1332         const int yychecklim = yylast_ - yyn + 1;
1333         const int yyxend     = yychecklim < YYNTOKENS ? yychecklim : YYNTOKENS;
1334         for (int yyx = yyxbegin; yyx < yyxend; ++yyx)
1335           if (yycheck_[yyx + yyn] == yyx && yyx != ]b4_symbol(error, kind)[
1336               && !yy_table_value_is_error_ (yytable_[yyx + yyn]))
1337           {
1338               if (!yyarg)
1339                   ++yycount;
1340               else if (yycount == yyargn)
1341                   return 0;
1342               else
1343                   yyarg[yycount++] = YY_CAST(symbol_kind_type, yyx);
1344           }
1345       }
1346 ]])[
1347     if (yyarg && yycount == 0 && 0 < yyargn)
1348       yyarg[0] = ]b4_symbol(empty, kind)[;
1349     return yycount;
1350   }
1351 
1352 ]])[
1353 
1354 ]b4_lac_if([[
1355   bool
1356   ]b4_parser_class[::yy_lac_check_ (symbol_kind_type yytoken) const
1357   {
1358     // Logically, the yylac_stack's lifetime is confined to this function.
1359     // Clear it, to get rid of potential left-overs from previous call.
1360     yylac_stack_.clear();
1361     // Reduce until we encounter a shift and thereby accept the token.
1362 #if] b4_api_PREFIX[DEBUG
1363     YYCDEBUG << "LAC: checking lookahead " << symbol_name(yytoken) << ':';
1364 #endif
1365     std::ptrdiff_t lac_top = 0;
1366     while (true)
1367     {
1368         state_type top_state =
1369             (yylac_stack_.empty() ? yystack_[lac_top].state : yylac_stack_.back());
1370         int yyrule = yypact_[+top_state];
1371         if (yy_pact_value_is_default_(yyrule) || (yyrule += yytoken) < 0 || yylast_ < yyrule ||
1372             yycheck_[yyrule] != yytoken)
1373         {
1374             // Use the default action.
1375             yyrule = yydefact_[+top_state];
1376             if (yyrule == 0)
1377             {
1378                 YYCDEBUG << " Err\n";
1379                 return false;
1380             }
1381         }
1382         else
1383         {
1384             // Use the action from yytable.
1385             yyrule = yytable_[yyrule];
1386             if (yy_table_value_is_error_(yyrule))
1387             {
1388                 YYCDEBUG << " Err\n";
1389                 return false;
1390             }
1391             if (0 < yyrule)
1392             {
1393                 YYCDEBUG << " S" << yyrule << '\n';
1394                 return true;
1395             }
1396             yyrule = -yyrule;
1397         }
1398         // By now we know we have to simulate a reduce.
1399         YYCDEBUG << " R" << yyrule - 1;
1400         // Pop the corresponding number of values from the stack.
1401         {
1402             std::ptrdiff_t yylen = yyr2_[yyrule];
1403             // First pop from the LAC stack as many tokens as possible.
1404             std::ptrdiff_t lac_size = std::ptrdiff_t(yylac_stack_.size());
1405             if (yylen < lac_size)
1406             {
1407                 yylac_stack_.resize(std::size_t(lac_size - yylen));
1408                 yylen = 0;
1409             }
1410             else if (lac_size)
1411             {
1412                 yylac_stack_.clear();
1413                 yylen -= lac_size;
1414             }
1415             // Only afterwards look at the main stack.
1416             // We simulate popping elements by incrementing lac_top.
1417             lac_top += yylen;
1418         }
1419         // Keep top_state in sync with the updated stack.
1420         top_state = (yylac_stack_.empty() ? yystack_[lac_top].state : yylac_stack_.back());
1421         // Push the resulting state of the reduction.
1422         state_type state = yy_lr_goto_state_(top_state, yyr1_[yyrule]);
1423         YYCDEBUG << " G" << int(state);
1424         yylac_stack_.push_back(state);
1425     }
1426   }
1427 
1428   // Establish the initial context if no initial context currently exists.
1429   bool
1430   ]b4_parser_class[::yy_lac_establish_ (symbol_kind_type yytoken)
1431   {
1432     /* Establish the initial context for the current lookahead if no initial
1433        context is currently established.
1434 
1435        We define a context as a snapshot of the parser stacks.  We define
1436        the initial context for a lookahead as the context in which the
1437        parser initially examines that lookahead in order to select a
1438        syntactic action.  Thus, if the lookahead eventually proves
1439        syntactically unacceptable (possibly in a later context reached via a
1440        series of reductions), the initial context can be used to determine
1441        the exact set of tokens that would be syntactically acceptable in the
1442        lookahead's place.  Moreover, it is the context after which any
1443        further semantic actions would be erroneous because they would be
1444        determined by a syntactically unacceptable token.
1445 
1446        yy_lac_establish_ should be invoked when a reduction is about to be
1447        performed in an inconsistent state (which, for the purposes of LAC,
1448        includes consistent states that don't know they're consistent because
1449        their default reductions have been disabled).
1450 
1451        For parse.lac=full, the implementation of yy_lac_establish_ is as
1452        follows.  If no initial context is currently established for the
1453        current lookahead, then check if that lookahead can eventually be
1454        shifted if syntactic actions continue from the current context.  */
1455     if (yy_lac_established_)
1456         return true;
1457     else
1458     {
1459 #if] b4_api_PREFIX[DEBUG
1460         YYCDEBUG << "LAC: initial context established for " << symbol_name(yytoken) << '\n';
1461 #endif
1462         yy_lac_established_ = true;
1463         return yy_lac_check_(yytoken);
1464     }
1465   }
1466 
1467   // Discard any previous initial lookahead context.
1468   void
1469   ]b4_parser_class[::yy_lac_discard_ (const char* event)
1470   {
1471     /* Discard any previous initial lookahead context because of Event,
1472        which may be a lookahead change or an invalidation of the currently
1473        established initial context for the current lookahead.
1474 
1475        The most common example of a lookahead change is a shift.  An example
1476        of both cases is syntax error recovery.  That is, a syntax error
1477        occurs when the lookahead is syntactically erroneous for the
1478        currently established initial context, so error recovery manipulates
1479        the parser stacks to try to find a new initial context in which the
1480        current lookahead is syntactically acceptable.  If it fails to find
1481        such a context, it discards the lookahead.  */
1482     if (yy_lac_established_)
1483     {
1484         YYCDEBUG << "LAC: initial context discarded due to " << event << '\n';
1485         yy_lac_established_ = false;
1486     }
1487   }]])[
1488 
1489 ]b4_parse_error_bmatch([detailed\|verbose], [[
1490   int
1491   ]b4_parser_class[::yy_syntax_error_arguments_ (const context& yyctx,
1492                                                  symbol_kind_type yyarg[], int yyargn) const
1493   {
1494     /* There are many possibilities here to consider:
1495        - If this state is a consistent state with a default action, then
1496          the only way this function was invoked is if the default action
1497          is an error action.  In that case, don't check for expected
1498          tokens because there are none.
1499        - The only way there can be no lookahead present (in yyla) is
1500          if this state is a consistent state with a default action.
1501          Thus, detecting the absence of a lookahead is sufficient to
1502          determine that there is no unexpected or expected token to
1503          report.  In that case, just report a simple "syntax error".
1504        - Don't assume there isn't a lookahead just because this state is
1505          a consistent state with a default action.  There might have
1506          been a previous inconsistent state, consistent state with a
1507          non-default action, or user semantic action that manipulated
1508          yyla.  (However, yyla is currently not documented for users.)]b4_lac_if([[
1509          In the first two cases, it might appear that the current syntax
1510          error should have been detected in the previous state when
1511          yy_lac_check was invoked.  However, at that time, there might
1512          have been a different syntax error that discarded a different
1513          initial context during error recovery, leaving behind the
1514          current lookahead.]], [[
1515        - Of course, the expected token list depends on states to have
1516          correct lookahead information, and it depends on the parser not
1517          to perform extra reductions after fetching a lookahead from the
1518          scanner and before detecting a syntax error.  Thus, state merging
1519          (from LALR or IELR) and default reductions corrupt the expected
1520          token list.  However, the list is correct for canonical LR with
1521          one exception: it will still contain any token that will not be
1522          accepted due to an error action in a later state.]])[
1523     */
1524 
1525     if (!yyctx.lookahead().empty())
1526     {
1527         if (yyarg)
1528             yyarg[0] = yyctx.token();
1529         int yyn = yyctx.expected_tokens(yyarg ? yyarg + 1 : yyarg, yyargn - 1);
1530         return yyn + 1;
1531     }
1532     return 0;
1533   }
1534 
1535   // Generate an error message.
1536   std::string
1537   ]b4_parser_class[::yysyntax_error_ (const context& yyctx) const
1538   {
1539     // Its maximum.
1540     enum
1541     {
1542         YYARGS_MAX = 5
1543     };
1544     // Arguments of yyformat.
1545     symbol_kind_type yyarg[YYARGS_MAX];
1546     int yycount = yy_syntax_error_arguments_(yyctx, yyarg, YYARGS_MAX);
1547 
1548     char const *yyformat = YY_NULLPTR;
1549     switch (yycount)
1550     {
1551 #define YYCASE_(N, S) \
1552     case N:           \
1553         yyformat = S; \
1554         break
1555         default:  // Avoid compiler warnings.
1556             YYCASE_(0, YY_("syntax error"));
1557             YYCASE_(1, YY_("syntax error, unexpected %s"));
1558             YYCASE_(2, YY_("syntax error, unexpected %s, expecting %s"));
1559             YYCASE_(3, YY_("syntax error, unexpected %s, expecting %s or %s"));
1560             YYCASE_(4, YY_("syntax error, unexpected %s, expecting %s or %s or %s"));
1561             YYCASE_(5, YY_("syntax error, unexpected %s, expecting %s or %s or %s or %s"));
1562 #undef YYCASE_
1563     }
1564 
1565     std::string yyres;
1566     // Argument number.
1567     std::ptrdiff_t yyi = 0;
1568     for (char const *yyp = yyformat; *yyp; ++yyp)
1569         if (yyp[0] == '%' && yyp[1] == 's' && yyi < yycount)
1570         {
1571             yyres += symbol_name(yyarg[yyi++]);
1572             ++yyp;
1573         }
1574         else
1575             yyres += *yyp;
1576     return yyres;
1577   }]])[
1578 
1579 
1580   const ]b4_int_type(b4_pact_ninf, b4_pact_ninf) b4_parser_class::yypact_ninf_ = b4_pact_ninf[;
1581 
1582   const ]b4_int_type(b4_table_ninf, b4_table_ninf) b4_parser_class::yytable_ninf_ = b4_table_ninf[;
1583 
1584 ]b4_parser_tables_define[
1585 
1586 ]b4_parse_error_bmatch([simple\|verbose],
1587 [[#if ]b4_api_PREFIX[DEBUG]b4_tname_if([[ || 1]])[
1588   // YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
1589   // First, the terminals, then, starting at \a YYNTOKENS, nonterminals.
1590   const char*
1591   const ]b4_parser_class[::yytname_[] =
1592   {
1593   ]b4_tname[
1594   };
1595 #endif
1596 ]])[
1597 
1598 #if] b4_api_PREFIX[DEBUG][
1599 ]b4_integral_parser_table_define([rline], [b4_rline])[
1600 
1601   void
1602   ]b4_parser_class[::yy_stack_print_ () const
1603   {
1604     *yycdebug_ << "Stack now";
1605     for (stack_type::const_iterator i = yystack_.begin(), i_end = yystack_.end(); i != i_end; ++i)
1606         *yycdebug_ << ' ' << int(i->state);
1607     *yycdebug_ << '\n';
1608   }
1609 
1610   void
1611   ]b4_parser_class[::yy_reduce_print_ (int yyrule) const
1612   {
1613     int yylno  = yyrline_[yyrule];
1614     int yynrhs = yyr2_[yyrule];
1615     // Print the symbols being reduced, and their result.
1616     *yycdebug_ << "Reducing stack by rule " << yyrule - 1 << " (line " << yylno << "):\n";
1617     // The symbols being reduced.
1618     for (int yyi = 0; yyi < yynrhs; yyi++)
1619       YY_SYMBOL_PRINT ("   $" << yyi + 1 << " =",
1620                        ]b4_rhs_data(yynrhs, yyi + 1)[);
1621   }
1622 #endif  // ]b4_api_PREFIX[DEBUG
1623 
1624 ]b4_token_ctor_if([], [b4_yytranslate_define([cc])])[
1625 ]b4_namespace_close[
1626 ]b4_epilogue[]dnl
1627 b4_output_end
1628 
1629 
1630 m4_popdef([b4_copyright_years])dnl
1631