# Java skeleton for Bison -*- autoconf -*-
-# Copyright (C) 2007, 2008 Free Software Foundation, Inc.
+# Copyright (C) 2007-2011 Free Software Foundation, Inc.
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
m4_include(b4_pkgdatadir/[java.m4])
-b4_defines_if([b4_fatal([%s: %%defines does not make sense in Java], [b4_skeleton])])
-m4_ifval(m4_defn([b4_symbol_destructors]),
- [b4_fatal([%s: %%destructor does not make sense in Java], [b4_skeleton])],
- [])
+b4_defines_if([b4_fatal([%s: %%defines does not make sense in Java],
+ [b4_skeleton])])
+
+# We don't depend on %debug in Java, but pacify warnings about non-used flags.
+b4_parse_trace_if([0], [0])
+
+m4_define([b4_symbol_no_destructor_assert],
+[b4_symbol_if([$1], [has_destructor],
+ [b4_fatal([%s: %s: %%destructor does not make sense in Java],
+ [b4_skeleton],
+ [b4_symbol_action_location([$1], [destructor])])])])
+b4_symbol_foreach([b4_symbol_no_destructor_assert])
m4_divert_push(0)dnl
@output(b4_parser_file_name@)@
b4_copyright([Skeleton implementation for Bison LALR(1) parsers in Java],
- [2007, 2008])
+ [2007-2011])
b4_percent_define_ifdef([package], [package b4_percent_define_get([package]);
])[/* First part of user declarations. */
private ]b4_location_type[ yylloc (YYStack rhs, int n)
{
if (n > 0)
- return new ]b4_location_type[ (rhs.locationAt (1).begin, rhs.locationAt (n).end);
+ return new ]b4_location_type[ (rhs.locationAt (n-1).begin, rhs.locationAt (0).end);
else
return new ]b4_location_type[ (rhs.locationAt (0).end);
}]])[
* printing an error message. */
public static final int YYERROR = 2;
- /**
- * Returned by a Bison action in order to print an error message and start
- * error recovery. */
- public static final int YYFAIL = 3;
-
+ // Internal return codes that are not supported for user semantic
+ // actions.
+ private static final int YYERRLAB = 3;
private static final int YYNEWSTATE = 4;
private static final int YYDEFAULT = 5;
private static final int YYREDUCE = 6;
/* Take a decision. First try without lookahead. */
yyn = yypact_[yystate];
- if (yyn == yypact_ninf_)
+ if (yy_pact_value_is_default_ (yyn))
{
label = YYDEFAULT;
break;
/* <= 0 means reduce or error. */
else if ((yyn = yytable_[yyn]) <= 0)
{
- if (yyn == 0 || yyn == yytable_ninf_)
- label = YYFAIL;
+ if (yy_table_value_is_error_ (yyn))
+ label = YYERRLAB;
else
{
yyn = -yyn;
case YYDEFAULT:
yyn = yydefact_[yystate];
if (yyn == 0)
- label = YYFAIL;
+ label = YYERRLAB;
else
label = YYREDUCE;
break;
/*------------------------------------.
| yyerrlab -- here on detecting error |
`------------------------------------*/
- case YYFAIL:
+ case YYERRLAB:
/* If not already recovering from an error, report this error. */
if (yyerrstatus_ == 0)
{
++yynerrs_;
+ if (yychar == yyempty_)
+ yytoken = yyempty_;
yyerror (]b4_locations_if([yylloc, ])[yysyntax_error (yystate, yytoken));
}
for (;;)
{
yyn = yypact_[yystate];
- if (yyn != yypact_ninf_)
+ if (!yy_pact_value_is_default_ (yyn))
{
yyn += yyterror_;
if (0 <= yyn && yyn <= yylast_ && yycheck_[yyn] == yyterror_)
{]b4_error_verbose_if([[
if (yyErrorVerbose)
{
- int yyn = yypact_[yystate];
- if (yypact_ninf_ < yyn && yyn <= yylast_)
+ /* There are many possibilities here to consider:
+ - Assume YYFAIL is not used. It's too flawed to consider.
+ See
+ <http://lists.gnu.org/archive/html/bison-patches/2009-12/msg00024.html>
+ for details. YYERROR is fine as it does not invoke this
+ function.
+ - If this state is a consistent state with a default action,
+ then the only way this function was invoked is if the
+ default action is an error action. In that case, don't
+ check for expected tokens because there are none.
+ - The only way there can be no lookahead present (in tok) is
+ if this state is a consistent state with a default action.
+ Thus, detecting the absence of a lookahead is sufficient to
+ determine that there is no unexpected or expected token to
+ report. In that case, just report a simple "syntax error".
+ - Don't assume there isn't a lookahead just because this
+ state is a consistent state with a default action. There
+ might have been a previous inconsistent state, consistent
+ state with a non-default action, or user semantic action
+ that manipulated yychar. (However, yychar is currently out
+ of scope during semantic actions.)
+ - Of course, the expected token list depends on states to
+ have correct lookahead information, and it depends on the
+ parser not to perform extra reductions after fetching a
+ lookahead from the scanner and before detecting a syntax
+ error. Thus, state merging (from LALR or IELR) and default
+ reductions corrupt the expected token list. However, the
+ list is correct for canonical LR with one exception: it
+ will still contain any token that will not be accepted due
+ to an error action in a later state.
+ */
+ if (tok != yyempty_)
{
- StringBuffer res;
-
- /* Start YYX at -YYN if negative to avoid negative indexes in
- YYCHECK. */
- int yyxbegin = yyn < 0 ? -yyn : 0;
-
- /* Stay within bounds of both yycheck and yytname. */
- int yychecklim = yylast_ - yyn + 1;
- int yyxend = yychecklim < yyntokens_ ? yychecklim : yyntokens_;
- int count = 0;
- for (int x = yyxbegin; x < yyxend; ++x)
- if (yycheck_[x + yyn] == x && x != yyterror_)
- ++count;
-
// FIXME: This method of building the message is not compatible
// with internationalization.
- res = new StringBuffer ("syntax error, unexpected ");
+ StringBuffer res =
+ new StringBuffer ("syntax error, unexpected ");
res.append (yytnamerr_ (yytname_[tok]));
- if (count < 5)
+ int yyn = yypact_[yystate];
+ if (!yy_pact_value_is_default_ (yyn))
{
- count = 0;
+ /* Start YYX at -YYN if negative to avoid negative
+ indexes in YYCHECK. In other words, skip the first
+ -YYN actions for this state because they are default
+ actions. */
+ int yyxbegin = yyn < 0 ? -yyn : 0;
+ /* Stay within bounds of both yycheck and yytname. */
+ int yychecklim = yylast_ - yyn + 1;
+ int yyxend = yychecklim < yyntokens_ ? yychecklim : yyntokens_;
+ int count = 0;
for (int x = yyxbegin; x < yyxend; ++x)
- if (yycheck_[x + yyn] == x && x != yyterror_)
- {
- res.append (count++ == 0 ? ", expecting " : " or ");
- res.append (yytnamerr_ (yytname_[x]));
- }
+ if (yycheck_[x + yyn] == x && x != yyterror_
+ && !yy_table_value_is_error_ (yytable_[x + yyn]))
+ ++count;
+ if (count < 5)
+ {
+ count = 0;
+ for (int x = yyxbegin; x < yyxend; ++x)
+ if (yycheck_[x + yyn] == x && x != yyterror_
+ && !yy_table_value_is_error_ (yytable_[x + yyn]))
+ {
+ res.append (count++ == 0 ? ", expecting " : " or ");
+ res.append (yytnamerr_ (yytname_[x]));
+ }
+ }
}
- return res.toString ();
+ return res.toString ();
}
}
]])[
return "syntax error";
}
- /* YYPACT[STATE-NUM] -- Index in YYTABLE of the portion describing
- STATE-NUM. */
- private static final ]b4_int_type_for([b4_pact])[ yypact_ninf_ = ]b4_pact_ninf[;
- ]b4_integral_parser_table([yypact_], [b4_pact])[
-
- /* YYDEFACT[S] -- default rule to reduce with in state S when YYTABLE
- doesn't specify something else to do. Zero means the default is an
- error. */
- ]b4_integral_parser_table([yydefact_], [b4_defact])[
-
- /* YYPGOTO[NTERM-NUM]. */
- ]b4_integral_parser_table([yypgoto_], [b4_pgoto])[
+ /**
+ * Whether the given <code>yypact_</code> value indicates a defaulted state.
+ * @@param yyvalue the value to check
+ */
+ private static boolean yy_pact_value_is_default_ (int yyvalue)
+ {
+ return yyvalue == yypact_ninf_;
+ }
- /* YYDEFGOTO[NTERM-NUM]. */
- ]b4_integral_parser_table([yydefgoto_], [b4_defgoto])[
+ /**
+ * Whether the given <code>yytable_</code> value indicates a syntax error.
+ * @@param yyvalue the value to check
+ */
+ private static boolean yy_table_value_is_error_ (int yyvalue)
+ {
+ return yyvalue == yytable_ninf_;
+ }
- /* YYTABLE[YYPACT[STATE-NUM]]. What to do in state STATE-NUM. If
- positive, shift that token. If negative, reduce the rule which
- number is the opposite. If zero, do what YYDEFACT says. */
+ private static final ]b4_int_type_for([b4_pact])[ yypact_ninf_ = ]b4_pact_ninf[;
private static final ]b4_int_type_for([b4_table])[ yytable_ninf_ = ]b4_table_ninf[;
- ]b4_integral_parser_table([yytable_], [b4_table])[
- /* YYCHECK. */
- ]b4_integral_parser_table([yycheck_], [b4_check])[
-
- /* STOS_[STATE-NUM] -- The (internal number of the) accessing
- symbol of state STATE-NUM. */
- ]b4_integral_parser_table([yystos_], [b4_stos])[
-
- /* TOKEN_NUMBER_[YYLEX-NUM] -- Internal symbol number corresponding
- to YYLEX-NUM. */
- ]b4_integral_parser_table([yytoken_number_], [b4_toknum])[
-
- /* YYR1[YYN] -- Symbol number of symbol that rule YYN derives. */
- ]b4_integral_parser_table([yyr1_], [b4_r1])[
-
- /* YYR2[YYN] -- Number of symbols composing right hand side of rule YYN. */
- ]b4_integral_parser_table([yyr2_], [b4_r2])[
+ ]b4_parser_tables_define[
+ ]b4_integral_parser_table_define([token_number], [b4_toknum],
+ [TOKEN_NUMBER_[YYLEX-NUM] -- Internal symbol number corresponding
+ to YYLEX-NUM.])[
/* YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
First, the terminals, then, starting at \a yyntokens_, nonterminals. */
- ]b4_typed_parser_table([String], [yytname_], [b4_tname])[
-
- /* YYRHS -- A `-1'-separated list of the rules' RHS. */
- ]b4_integral_parser_table([yyrhs_], [b4_rhs])[
-
- /* YYPRHS[YYN] -- Index of the first RHS symbol of rule number YYN in
- YYRHS. */
- ]b4_integral_parser_table([yyprhs_], [b4_prhs])[
+ ]b4_typed_parser_table_define([String], [tname], [b4_tname])[
- /* YYRLINE[YYN] -- Source line where rule number YYN was defined. */
- ]b4_integral_parser_table([yyrline_], [b4_rline])[
+ ]b4_integral_parser_table_define([rline], [b4_rline],
+ [YYRLINE[YYN] -- Source line where rule number YYN was defined.])[
// Report on the debug stream that the rule yyrule is going to be reduced.
private void yy_reduce_print (int yyrule, YYStack yystack)
/* The symbols being reduced. */
for (int yyi = 0; yyi < yynrhs; yyi++)
yy_symbol_print (" $" + (yyi + 1) + " =",
- yyrhs_[yyprhs_[yyrule] + yyi],
+ yystos_[yystack.stateAt(yyi + 1 - yynrhs)],
]b4_rhs_value(yynrhs, yyi + 1)b4_locations_if([,
b4_rhs_location(yynrhs, yyi + 1)])[);
}
/* YYTRANSLATE(YYLEX) -- Bison symbol number corresponding to YYLEX. */
- ]b4_integral_parser_table([yytranslate_table_], [b4_translate])[
+ ]b4_integral_parser_table_define([translate_table], [b4_translate])[
private static final ]b4_int_type_for([b4_translate])[ yytranslate_ (int t)
{
}
-b4_epilogue
+b4_epilogue[]dnl
m4_divert_pop(0)dnl