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1 # Java skeleton for Bison -*- autoconf -*-
2
3 # Copyright (C) 2007-2012 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 <http://www.gnu.org/licenses/>.
17
18 m4_include(b4_pkgdatadir/[java.m4])
19
20 b4_defines_if([b4_fatal([%s: %%defines does not make sense in Java],
21 [b4_skeleton])])
22
23 # We don't depend on %debug in Java, but pacify warnings about non-used flags.
24 b4_parse_trace_if([0], [0])
25
26 m4_define([b4_symbol_no_destructor_assert],
27 [b4_symbol_if([$1], [has_destructor],
28 [b4_fatal([%s: %s: %%destructor does not make sense in Java],
29 [b4_skeleton],
30 [b4_symbol_action_location([$1], [destructor])])])])
31 b4_symbol_foreach([b4_symbol_no_destructor_assert])
32
33 m4_divert_push(0)dnl
34 @output(b4_parser_file_name@)@
35 b4_copyright([Skeleton implementation for Bison LALR(1) parsers in Java],
36 [2007-2012])
37
38 b4_percent_define_ifdef([package], [package b4_percent_define_get([package]);
39 ])[/* First part of user declarations. */
40 ]b4_user_pre_prologue
41 b4_user_post_prologue
42 b4_percent_code_get([[imports]])
43 [/**
44 * A Bison parser, automatically generated from <tt>]m4_bpatsubst(b4_file_name, [^"\(.*\)"$], [\1])[</tt>.
45 *
46 * @@author LALR (1) parser skeleton written by Paolo Bonzini.
47 */
48 ]b4_percent_define_get3([annotations], [], [ ])dnl
49 b4_public_if([public ])dnl
50 b4_abstract_if([abstract ])dnl
51 b4_final_if([final ])dnl
52 b4_strictfp_if([strictfp ])dnl
53 [class ]b4_parser_class_name[]dnl
54 b4_percent_define_get3([extends], [ extends ])dnl
55 b4_percent_define_get3([implements], [ implements ])[
56 {
57 ]b4_identification[
58 ]b4_error_verbose_if([[
59 /** True if verbose error messages are enabled. */
60 private boolean yyErrorVerbose = true;
61
62 /**
63 * Return whether verbose error messages are enabled.
64 */
65 public final boolean getErrorVerbose() { return yyErrorVerbose; }
66
67 /**
68 * Set the verbosity of error messages.
69 * @@param verbose True to request verbose error messages.
70 */
71 public final void setErrorVerbose(boolean verbose)
72 { yyErrorVerbose = verbose; }
73 ]])
74
75 b4_locations_if([[
76 /**
77 * A class defining a pair of positions. Positions, defined by the
78 * <code>]b4_position_type[</code> class, denote a point in the input.
79 * Locations represent a part of the input through the beginning
80 * and ending positions. */
81 public class ]b4_location_type[ {
82 /** The first, inclusive, position in the range. */
83 public ]b4_position_type[ begin;
84
85 /** The first position beyond the range. */
86 public ]b4_position_type[ end;
87
88 /**
89 * Create a <code>]b4_location_type[</code> denoting an empty range located at
90 * a given point.
91 * @@param loc The position at which the range is anchored. */
92 public ]b4_location_type[ (]b4_position_type[ loc) {
93 this.begin = this.end = loc;
94 }
95
96 /**
97 * Create a <code>]b4_location_type[</code> from the endpoints of the range.
98 * @@param begin The first position included in the range.
99 * @@param end The first position beyond the range. */
100 public ]b4_location_type[ (]b4_position_type[ begin, ]b4_position_type[ end) {
101 this.begin = begin;
102 this.end = end;
103 }
104
105 /**
106 * Print a representation of the location. For this to be correct,
107 * <code>]b4_position_type[</code> should override the <code>equals</code>
108 * method. */
109 public String toString () {
110 if (begin.equals (end))
111 return begin.toString ();
112 else
113 return begin.toString () + "-" + end.toString ();
114 }
115 }
116
117 ]])
118
119 b4_locations_if([[
120 private ]b4_location_type[ yylloc (YYStack rhs, int n)
121 {
122 if (n > 0)
123 return new ]b4_location_type[ (rhs.locationAt (n-1).begin, rhs.locationAt (0).end);
124 else
125 return new ]b4_location_type[ (rhs.locationAt (0).end);
126 }]])[
127
128 /**
129 * Communication interface between the scanner and the Bison-generated
130 * parser <tt>]b4_parser_class_name[</tt>.
131 */
132 public interface Lexer {
133 /** Token returned by the scanner to signal the end of its input. */
134 public static final int EOF = 0;
135
136 ]b4_token_enums[
137
138 ]b4_locations_if([[/**
139 * Method to retrieve the beginning position of the last scanned token.
140 * @@return the position at which the last scanned token starts. */
141 ]b4_position_type[ getStartPos ();
142
143 /**
144 * Method to retrieve the ending position of the last scanned token.
145 * @@return the first position beyond the last scanned token. */
146 ]b4_position_type[ getEndPos ();]])[
147
148 /**
149 * Method to retrieve the semantic value of the last scanned token.
150 * @@return the semantic value of the last scanned token. */
151 ]b4_yystype[ getLVal ();
152
153 /**
154 * Entry point for the scanner. Returns the token identifier corresponding
155 * to the next token and prepares to return the semantic value
156 * ]b4_locations_if([and beginning/ending positions ])[of the token.
157 * @@return the token identifier corresponding to the next token. */
158 int yylex () ]b4_maybe_throws([b4_lex_throws])[;
159
160 /**
161 * Entry point for error reporting. Emits an error
162 * ]b4_locations_if([referring to the given location ])[in a user-defined way.
163 *
164 * ]b4_locations_if([[@@param loc The location of the element to which the
165 * error message is related]])[
166 * @@param msg The string for the error message. */
167 void yyerror (]b4_locations_if([b4_location_type[ loc, ]])[String msg);]
168 }
169
170 b4_lexer_if([[private class YYLexer implements Lexer {
171 ]b4_percent_code_get([[lexer]])[
172 }
173
174 ]])[/** The object doing lexical analysis for us. */
175 private Lexer yylexer;
176 ]
177 b4_parse_param_vars
178
179 b4_lexer_if([[
180 /**
181 * Instantiates the Bison-generated parser.
182 */
183 public ]b4_parser_class_name (b4_parse_param_decl([b4_lex_param_decl])[) ]b4_maybe_throws([b4_init_throws])[
184 {
185 ]b4_percent_code_get([[init]])[
186 this.yylexer = new YYLexer(]b4_lex_param_call[);
187 ]b4_parse_param_cons[
188 }
189 ]])
190
191 /**
192 * Instantiates the Bison-generated parser.
193 * @@param yylexer The scanner that will supply tokens to the parser.
194 */
195 b4_lexer_if([[protected]], [[public]]) b4_parser_class_name[ (]b4_parse_param_decl([[Lexer yylexer]])[) ]b4_maybe_throws([b4_init_throws])[
196 {
197 ]b4_percent_code_get([[init]])[
198 this.yylexer = yylexer;
199 ]b4_parse_param_cons[
200 }
201
202 private java.io.PrintStream yyDebugStream = System.err;
203
204 /**
205 * Return the <tt>PrintStream</tt> on which the debugging output is
206 * printed.
207 */
208 public final java.io.PrintStream getDebugStream () { return yyDebugStream; }
209
210 /**
211 * Set the <tt>PrintStream</tt> on which the debug output is printed.
212 * @@param s The stream that is used for debugging output.
213 */
214 public final void setDebugStream(java.io.PrintStream s) { yyDebugStream = s; }
215
216 private int yydebug = 0;
217
218 /**
219 * Answer the verbosity of the debugging output; 0 means that all kinds of
220 * output from the parser are suppressed.
221 */
222 public final int getDebugLevel() { return yydebug; }
223
224 /**
225 * Set the verbosity of the debugging output; 0 means that all kinds of
226 * output from the parser are suppressed.
227 * @@param level The verbosity level for debugging output.
228 */
229 public final void setDebugLevel(int level) { yydebug = level; }
230
231 /**
232 * Print an error message via the lexer.
233 *]b4_locations_if([[ Use a <code>null</code> location.]])[
234 * @@param msg The error message.
235 */
236 public final void yyerror (String msg)
237 {
238 yylexer.yyerror (]b4_locations_if([[(]b4_location_type[)null, ]])[msg);
239 }
240 ]b4_locations_if([[
241 /**
242 * Print an error message via the lexer.
243 * @@param loc The location associated with the message.
244 * @@param msg The error message.
245 */
246 public final void yyerror (]b4_location_type[ loc, String msg)
247 {
248 yylexer.yyerror (loc, msg);
249 }
250
251 /**
252 * Print an error message via the lexer.
253 * @@param pos The position associated with the message.
254 * @@param msg The error message.
255 */
256 public final void yyerror (]b4_position_type[ pos, String msg)
257 {
258 yylexer.yyerror (new ]b4_location_type[ (pos), msg);
259 }]])
260
261 [protected final void yycdebug (String s) {
262 if (yydebug > 0)
263 yyDebugStream.println (s);
264 }
265
266 private final class YYStack {
267 private int[] stateStack = new int[16];
268 ]b4_locations_if([[private ]b4_location_type[[] locStack = new ]b4_location_type[[16];]])[
269 private ]b4_yystype[[] valueStack = new ]b4_yystype[[16];
270
271 public int size = 16;
272 public int height = -1;
273
274 public final void push (int state, ]b4_yystype[ value]dnl
275 b4_locations_if([, ]b4_location_type[ loc])[) {
276 height++;
277 if (size == height)
278 {
279 int[] newStateStack = new int[size * 2];
280 System.arraycopy (stateStack, 0, newStateStack, 0, height);
281 stateStack = newStateStack;
282 ]b4_locations_if([[
283 ]b4_location_type[[] newLocStack = new ]b4_location_type[[size * 2];
284 System.arraycopy (locStack, 0, newLocStack, 0, height);
285 locStack = newLocStack;]])
286
287 b4_yystype[[] newValueStack = new ]b4_yystype[[size * 2];
288 System.arraycopy (valueStack, 0, newValueStack, 0, height);
289 valueStack = newValueStack;
290
291 size *= 2;
292 }
293
294 stateStack[height] = state;
295 ]b4_locations_if([[locStack[height] = loc;]])[
296 valueStack[height] = value;
297 }
298
299 public final void pop () {
300 pop (1);
301 }
302
303 public final void pop (int num) {
304 // Avoid memory leaks... garbage collection is a white lie!
305 if (num > 0) {
306 java.util.Arrays.fill (valueStack, height - num + 1, height + 1, null);
307 ]b4_locations_if([[java.util.Arrays.fill (locStack, height - num + 1, height + 1, null);]])[
308 }
309 height -= num;
310 }
311
312 public final int stateAt (int i) {
313 return stateStack[height - i];
314 }
315
316 ]b4_locations_if([[public final ]b4_location_type[ locationAt (int i) {
317 return locStack[height - i];
318 }
319
320 ]])[public final ]b4_yystype[ valueAt (int i) {
321 return valueStack[height - i];
322 }
323
324 // Print the state stack on the debug stream.
325 public void print (java.io.PrintStream out)
326 {
327 out.print ("Stack now");
328
329 for (int i = 0; i <= height; i++)
330 {
331 out.print (' ');
332 out.print (stateStack[i]);
333 }
334 out.println ();
335 }
336 }
337
338 /**
339 * Returned by a Bison action in order to stop the parsing process and
340 * return success (<tt>true</tt>). */
341 public static final int YYACCEPT = 0;
342
343 /**
344 * Returned by a Bison action in order to stop the parsing process and
345 * return failure (<tt>false</tt>). */
346 public static final int YYABORT = 1;
347
348 /**
349 * Returned by a Bison action in order to start error recovery without
350 * printing an error message. */
351 public static final int YYERROR = 2;
352
353 // Internal return codes that are not supported for user semantic
354 // actions.
355 private static final int YYERRLAB = 3;
356 private static final int YYNEWSTATE = 4;
357 private static final int YYDEFAULT = 5;
358 private static final int YYREDUCE = 6;
359 private static final int YYERRLAB1 = 7;
360 private static final int YYRETURN = 8;
361
362 private int yyerrstatus_ = 0;
363
364 /**
365 * Return whether error recovery is being done. In this state, the parser
366 * reads token until it reaches a known state, and then restarts normal
367 * operation. */
368 public final boolean recovering ()
369 {
370 return yyerrstatus_ == 0;
371 }
372
373 private int yyaction (int yyn, YYStack yystack, int yylen) ]b4_maybe_throws([b4_throws])[
374 {
375 ]b4_yystype[ yyval;
376 ]b4_locations_if([b4_location_type[ yyloc = yylloc (yystack, yylen);]])[
377
378 /* If YYLEN is nonzero, implement the default value of the action:
379 `$$ = $1'. Otherwise, use the top of the stack.
380
381 Otherwise, the following line sets YYVAL to garbage.
382 This behavior is undocumented and Bison
383 users should not rely upon it. */
384 if (yylen > 0)
385 yyval = yystack.valueAt (yylen - 1);
386 else
387 yyval = yystack.valueAt (0);
388
389 yy_reduce_print (yyn, yystack);
390
391 switch (yyn)
392 {
393 ]b4_user_actions[
394 default: break;
395 }
396
397 yy_symbol_print ("-> $$ =", yyr1_[yyn], yyval]b4_locations_if([, yyloc])[);
398
399 yystack.pop (yylen);
400 yylen = 0;
401
402 /* Shift the result of the reduction. */
403 yyn = yyr1_[yyn];
404 int yystate = yypgoto_[yyn - yyntokens_] + yystack.stateAt (0);
405 if (0 <= yystate && yystate <= yylast_
406 && yycheck_[yystate] == yystack.stateAt (0))
407 yystate = yytable_[yystate];
408 else
409 yystate = yydefgoto_[yyn - yyntokens_];
410
411 yystack.push (yystate, yyval]b4_locations_if([, yyloc])[);
412 return YYNEWSTATE;
413 }
414
415 ]b4_error_verbose_if([[
416 /* Return YYSTR after stripping away unnecessary quotes and
417 backslashes, so that it's suitable for yyerror. The heuristic is
418 that double-quoting is unnecessary unless the string contains an
419 apostrophe, a comma, or backslash (other than backslash-backslash).
420 YYSTR is taken from yytname. */
421 private final String yytnamerr_ (String yystr)
422 {
423 if (yystr.charAt (0) == '"')
424 {
425 StringBuffer yyr = new StringBuffer ();
426 strip_quotes: for (int i = 1; i < yystr.length (); i++)
427 switch (yystr.charAt (i))
428 {
429 case '\'':
430 case ',':
431 break strip_quotes;
432
433 case '\\':
434 if (yystr.charAt(++i) != '\\')
435 break strip_quotes;
436 /* Fall through. */
437 default:
438 yyr.append (yystr.charAt (i));
439 break;
440
441 case '"':
442 return yyr.toString ();
443 }
444 }
445 else if (yystr.equals ("$end"))
446 return "end of input";
447
448 return yystr;
449 }
450 ]])[
451
452 /*--------------------------------.
453 | Print this symbol on YYOUTPUT. |
454 `--------------------------------*/
455
456 private void yy_symbol_print (String s, int yytype,
457 ]b4_yystype[ yyvaluep]dnl
458 b4_locations_if([, Object yylocationp])[)
459 {
460 if (yydebug > 0)
461 yycdebug (s + (yytype < yyntokens_ ? " token " : " nterm ")
462 + yytname_[yytype] + " ("]b4_locations_if([
463 + yylocationp + ": "])[
464 + (yyvaluep == null ? "(null)" : yyvaluep.toString ()) + ")");
465 }
466
467 /**
468 * Parse input from the scanner that was specified at object construction
469 * time. Return whether the end of the input was reached successfully.
470 *
471 * @@return <tt>true</tt> if the parsing succeeds. Note that this does not
472 * imply that there were no syntax errors.
473 */
474 public boolean parse () ]b4_maybe_throws([b4_list2([b4_lex_throws], [b4_throws])])[
475 {
476 /// Lookahead and lookahead in internal form.
477 int yychar = yyempty_;
478 int yytoken = 0;
479
480 /* State. */
481 int yyn = 0;
482 int yylen = 0;
483 int yystate = 0;
484
485 YYStack yystack = new YYStack ();
486
487 /* Error handling. */
488 int yynerrs_ = 0;
489 ]b4_locations_if([/// The location where the error started.
490 ]b4_location_type[ yyerrloc = null;
491
492 /// ]b4_location_type[ of the lookahead.
493 ]b4_location_type[ yylloc = new ]b4_location_type[ (null, null);
494
495 /// @@$.
496 ]b4_location_type[ yyloc;])
497
498 /// Semantic value of the lookahead.
499 b4_yystype[ yylval = null;
500
501 yycdebug ("Starting parse\n");
502 yyerrstatus_ = 0;
503
504 ]m4_ifdef([b4_initial_action], [
505 b4_dollar_pushdef([yylval], [], [yylloc])dnl
506 /* User initialization code. */
507 b4_user_initial_action
508 b4_dollar_popdef])[]dnl
509
510 [ /* Initialize the stack. */
511 yystack.push (yystate, yylval]b4_locations_if([, yylloc])[);
512
513 int label = YYNEWSTATE;
514 for (;;)
515 switch (label)
516 {
517 /* New state. Unlike in the C/C++ skeletons, the state is already
518 pushed when we come here. */
519 case YYNEWSTATE:
520 yycdebug ("Entering state " + yystate + "\n");
521 if (yydebug > 0)
522 yystack.print (yyDebugStream);
523
524 /* Accept? */
525 if (yystate == yyfinal_)
526 return true;
527
528 /* Take a decision. First try without lookahead. */
529 yyn = yypact_[yystate];
530 if (yy_pact_value_is_default_ (yyn))
531 {
532 label = YYDEFAULT;
533 break;
534 }
535
536 /* Read a lookahead token. */
537 if (yychar == yyempty_)
538 {
539 yycdebug ("Reading a token: ");
540 yychar = yylexer.yylex ();]
541 b4_locations_if([[
542 yylloc = new ]b4_location_type[(yylexer.getStartPos (),
543 yylexer.getEndPos ());]])
544 yylval = yylexer.getLVal ();[
545 }
546
547 /* Convert token to internal form. */
548 if (yychar <= Lexer.EOF)
549 {
550 yychar = yytoken = Lexer.EOF;
551 yycdebug ("Now at end of input.\n");
552 }
553 else
554 {
555 yytoken = yytranslate_ (yychar);
556 yy_symbol_print ("Next token is", yytoken,
557 yylval]b4_locations_if([, yylloc])[);
558 }
559
560 /* If the proper action on seeing token YYTOKEN is to reduce or to
561 detect an error, take that action. */
562 yyn += yytoken;
563 if (yyn < 0 || yylast_ < yyn || yycheck_[yyn] != yytoken)
564 label = YYDEFAULT;
565
566 /* <= 0 means reduce or error. */
567 else if ((yyn = yytable_[yyn]) <= 0)
568 {
569 if (yy_table_value_is_error_ (yyn))
570 label = YYERRLAB;
571 else
572 {
573 yyn = -yyn;
574 label = YYREDUCE;
575 }
576 }
577
578 else
579 {
580 /* Shift the lookahead token. */
581 yy_symbol_print ("Shifting", yytoken,
582 yylval]b4_locations_if([, yylloc])[);
583
584 /* Discard the token being shifted. */
585 yychar = yyempty_;
586
587 /* Count tokens shifted since error; after three, turn off error
588 status. */
589 if (yyerrstatus_ > 0)
590 --yyerrstatus_;
591
592 yystate = yyn;
593 yystack.push (yystate, yylval]b4_locations_if([, yylloc])[);
594 label = YYNEWSTATE;
595 }
596 break;
597
598 /*-----------------------------------------------------------.
599 | yydefault -- do the default action for the current state. |
600 `-----------------------------------------------------------*/
601 case YYDEFAULT:
602 yyn = yydefact_[yystate];
603 if (yyn == 0)
604 label = YYERRLAB;
605 else
606 label = YYREDUCE;
607 break;
608
609 /*-----------------------------.
610 | yyreduce -- Do a reduction. |
611 `-----------------------------*/
612 case YYREDUCE:
613 yylen = yyr2_[yyn];
614 label = yyaction (yyn, yystack, yylen);
615 yystate = yystack.stateAt (0);
616 break;
617
618 /*------------------------------------.
619 | yyerrlab -- here on detecting error |
620 `------------------------------------*/
621 case YYERRLAB:
622 /* If not already recovering from an error, report this error. */
623 if (yyerrstatus_ == 0)
624 {
625 ++yynerrs_;
626 if (yychar == yyempty_)
627 yytoken = yyempty_;
628 yyerror (]b4_locations_if([yylloc, ])[yysyntax_error (yystate, yytoken));
629 }
630
631 ]b4_locations_if([yyerrloc = yylloc;])[
632 if (yyerrstatus_ == 3)
633 {
634 /* If just tried and failed to reuse lookahead token after an
635 error, discard it. */
636
637 if (yychar <= Lexer.EOF)
638 {
639 /* Return failure if at end of input. */
640 if (yychar == Lexer.EOF)
641 return false;
642 }
643 else
644 yychar = yyempty_;
645 }
646
647 /* Else will try to reuse lookahead token after shifting the error
648 token. */
649 label = YYERRLAB1;
650 break;
651
652 /*---------------------------------------------------.
653 | errorlab -- error raised explicitly by YYERROR. |
654 `---------------------------------------------------*/
655 case YYERROR:
656
657 ]b4_locations_if([yyerrloc = yystack.locationAt (yylen - 1);])[
658 /* Do not reclaim the symbols of the rule which action triggered
659 this YYERROR. */
660 yystack.pop (yylen);
661 yylen = 0;
662 yystate = yystack.stateAt (0);
663 label = YYERRLAB1;
664 break;
665
666 /*-------------------------------------------------------------.
667 | yyerrlab1 -- common code for both syntax error and YYERROR. |
668 `-------------------------------------------------------------*/
669 case YYERRLAB1:
670 yyerrstatus_ = 3; /* Each real token shifted decrements this. */
671
672 for (;;)
673 {
674 yyn = yypact_[yystate];
675 if (!yy_pact_value_is_default_ (yyn))
676 {
677 yyn += yyterror_;
678 if (0 <= yyn && yyn <= yylast_ && yycheck_[yyn] == yyterror_)
679 {
680 yyn = yytable_[yyn];
681 if (0 < yyn)
682 break;
683 }
684 }
685
686 /* Pop the current state because it cannot handle the error token. */
687 if (yystack.height == 0)
688 return false;
689
690 ]b4_locations_if([yyerrloc = yystack.locationAt (0);])[
691 yystack.pop ();
692 yystate = yystack.stateAt (0);
693 if (yydebug > 0)
694 yystack.print (yyDebugStream);
695 }
696
697 ]b4_locations_if([
698 /* Muck with the stack to setup for yylloc. */
699 yystack.push (0, null, yylloc);
700 yystack.push (0, null, yyerrloc);
701 yyloc = yylloc (yystack, 2);
702 yystack.pop (2);])[
703
704 /* Shift the error token. */
705 yy_symbol_print ("Shifting", yystos_[yyn],
706 yylval]b4_locations_if([, yyloc])[);
707
708 yystate = yyn;
709 yystack.push (yyn, yylval]b4_locations_if([, yyloc])[);
710 label = YYNEWSTATE;
711 break;
712
713 /* Accept. */
714 case YYACCEPT:
715 return true;
716
717 /* Abort. */
718 case YYABORT:
719 return false;
720 }
721 }
722
723 // Generate an error message.
724 private String yysyntax_error (int yystate, int tok)
725 {]b4_error_verbose_if([[
726 if (yyErrorVerbose)
727 {
728 /* There are many possibilities here to consider:
729 - If this state is a consistent state with a default action,
730 then the only way this function was invoked is if the
731 default action is an error action. In that case, don't
732 check for expected tokens because there are none.
733 - The only way there can be no lookahead present (in tok) is
734 if this state is a consistent state with a default action.
735 Thus, detecting the absence of a lookahead is sufficient to
736 determine that there is no unexpected or expected token to
737 report. In that case, just report a simple "syntax error".
738 - Don't assume there isn't a lookahead just because this
739 state is a consistent state with a default action. There
740 might have been a previous inconsistent state, consistent
741 state with a non-default action, or user semantic action
742 that manipulated yychar. (However, yychar is currently out
743 of scope during semantic actions.)
744 - Of course, the expected token list depends on states to
745 have correct lookahead information, and it depends on the
746 parser not to perform extra reductions after fetching a
747 lookahead from the scanner and before detecting a syntax
748 error. Thus, state merging (from LALR or IELR) and default
749 reductions corrupt the expected token list. However, the
750 list is correct for canonical LR with one exception: it
751 will still contain any token that will not be accepted due
752 to an error action in a later state.
753 */
754 if (tok != yyempty_)
755 {
756 // FIXME: This method of building the message is not compatible
757 // with internationalization.
758 StringBuffer res =
759 new StringBuffer ("syntax error, unexpected ");
760 res.append (yytnamerr_ (yytname_[tok]));
761 int yyn = yypact_[yystate];
762 if (!yy_pact_value_is_default_ (yyn))
763 {
764 /* Start YYX at -YYN if negative to avoid negative
765 indexes in YYCHECK. In other words, skip the first
766 -YYN actions for this state because they are default
767 actions. */
768 int yyxbegin = yyn < 0 ? -yyn : 0;
769 /* Stay within bounds of both yycheck and yytname. */
770 int yychecklim = yylast_ - yyn + 1;
771 int yyxend = yychecklim < yyntokens_ ? yychecklim : yyntokens_;
772 int count = 0;
773 for (int x = yyxbegin; x < yyxend; ++x)
774 if (yycheck_[x + yyn] == x && x != yyterror_
775 && !yy_table_value_is_error_ (yytable_[x + yyn]))
776 ++count;
777 if (count < 5)
778 {
779 count = 0;
780 for (int x = yyxbegin; x < yyxend; ++x)
781 if (yycheck_[x + yyn] == x && x != yyterror_
782 && !yy_table_value_is_error_ (yytable_[x + yyn]))
783 {
784 res.append (count++ == 0 ? ", expecting " : " or ");
785 res.append (yytnamerr_ (yytname_[x]));
786 }
787 }
788 }
789 return res.toString ();
790 }
791 }
792 ]])[
793 return "syntax error";
794 }
795
796 /**
797 * Whether the given <code>yypact_</code> value indicates a defaulted state.
798 * @@param yyvalue the value to check
799 */
800 private static boolean yy_pact_value_is_default_ (int yyvalue)
801 {
802 return yyvalue == yypact_ninf_;
803 }
804
805 /**
806 * Whether the given <code>yytable_</code> value indicates a syntax error.
807 * @@param yyvalue the value to check
808 */
809 private static boolean yy_table_value_is_error_ (int yyvalue)
810 {
811 return yyvalue == yytable_ninf_;
812 }
813
814 private static final ]b4_int_type_for([b4_pact])[ yypact_ninf_ = ]b4_pact_ninf[;
815 private static final ]b4_int_type_for([b4_table])[ yytable_ninf_ = ]b4_table_ninf[;
816
817 ]b4_parser_tables_define[
818 ]b4_integral_parser_table_define([token_number], [b4_toknum],
819 [TOKEN_NUMBER_[YYLEX-NUM] -- Internal symbol number corresponding
820 to YYLEX-NUM.])[
821
822 /* YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
823 First, the terminals, then, starting at \a yyntokens_, nonterminals. */
824 ]b4_typed_parser_table_define([String], [tname], [b4_tname])[
825
826 ]b4_integral_parser_table_define([rline], [b4_rline],
827 [YYRLINE[YYN] -- Source line where rule number YYN was defined.])[
828
829 // Report on the debug stream that the rule yyrule is going to be reduced.
830 private void yy_reduce_print (int yyrule, YYStack yystack)
831 {
832 if (yydebug == 0)
833 return;
834
835 int yylno = yyrline_[yyrule];
836 int yynrhs = yyr2_[yyrule];
837 /* Print the symbols being reduced, and their result. */
838 yycdebug ("Reducing stack by rule " + (yyrule - 1)
839 + " (line " + yylno + "), ");
840
841 /* The symbols being reduced. */
842 for (int yyi = 0; yyi < yynrhs; yyi++)
843 yy_symbol_print (" $" + (yyi + 1) + " =",
844 yystos_[yystack.stateAt(yynrhs - (yyi + 1))],
845 ]b4_rhs_value(yynrhs, yyi + 1)b4_locations_if([,
846 b4_rhs_location(yynrhs, yyi + 1)])[);
847 }
848
849 /* YYTRANSLATE(YYLEX) -- Bison symbol number corresponding to YYLEX. */
850 ]b4_integral_parser_table_define([translate_table], [b4_translate])[
851
852 private static final ]b4_int_type_for([b4_translate])[ yytranslate_ (int t)
853 {
854 if (t >= 0 && t <= yyuser_token_number_max_)
855 return yytranslate_table_[t];
856 else
857 return yyundef_token_;
858 }
859
860 private static final int yylast_ = ]b4_last[;
861 private static final int yynnts_ = ]b4_nterms_number[;
862 private static final int yyempty_ = -2;
863 private static final int yyfinal_ = ]b4_final_state_number[;
864 private static final int yyterror_ = 1;
865 private static final int yyerrcode_ = 256;
866 private static final int yyntokens_ = ]b4_tokens_number[;
867
868 private static final int yyuser_token_number_max_ = ]b4_user_token_number_max[;
869 private static final int yyundef_token_ = ]b4_undef_token_number[;
870
871 ]/* User implementation code. */
872 b4_percent_code_get[]dnl
873
874 }
875
876 b4_epilogue[]dnl
877 m4_divert_pop(0)dnl