m4_define([b4_shared_declarations],
[b4_percent_code_get([[requires]])[
]b4_parse_assert_if([# include <cassert>])[
-# include <vector>
+# include <cstdlib> // std::abort
# include <iostream>
# include <stdexcept>
-# include <string>]b4_defines_if([[
+# include <string>
+# include <vector>]b4_defines_if([[
# include "stack.hh"
]b4_bison_locations_if([[# include "location.hh"]])])[
]b4_variant_if([b4_variant_includes])[
/// Generate an error message.
/// \param yystate the state where the error occurred.
- /// \param yytoken the lookahead token type, or yyempty_.
+ /// \param yyla the lookahead token.
virtual std::string yysyntax_error_ (state_type yystate,
- symbol_number_type yytoken) const;
+ const symbol_type& yyla) const;
/// Compute post-reduction state.
/// \param yystate the current state
/// Copy constructor.
by_state (const by_state& other);
+ /// Record that this symbol is empty.
+ void clear ();
+
/// Steal the symbol type from \a that.
void move (by_state& that);
/// The (internal) type number (corresponding to \a state).
- /// \a empty when empty.
+ /// \a empty_symbol when empty.
symbol_number_type type_get () const;
/// The state number used to denote an empty symbol.
- enum { empty = 0 };
+ enum { empty_state = -1 };
/// The state.
/// \a empty when empty.
yyeof_ = 0,
yylast_ = ]b4_last[, ///< Last index in yytable_.
yynnts_ = ]b4_nterms_number[, ///< Number of nonterminal symbols.
- yyempty_ = -2,
yyfinal_ = ]b4_final_state_number[, ///< Termination state number.
yyterror_ = 1,
yyerrcode_ = 256,
#endif // !]b4_api_PREFIX[DEBUG
#define yyerrok (yyerrstatus_ = 0)
-#define yyclearin (yyempty = true)
+#define yyclearin (yyla.clear ())
#define YYACCEPT goto yyacceptlab
#define YYABORT goto yyabortlab
// by_state.
inline
]b4_parser_class_name[::by_state::by_state ()
- : state (empty)
+ : state (empty_state)
{}
inline
: state (other.state)
{}
+ inline
+ void
+ ]b4_parser_class_name[::by_state::clear ()
+ {
+ state = empty_state;
+ }
+
inline
void
]b4_parser_class_name[::by_state::move (by_state& that)
{
state = that.state;
- that.state = empty;
+ that.clear ();
}
inline
]b4_parser_class_name[::symbol_number_type
]b4_parser_class_name[::by_state::type_get () const
{
- return state == empty ? 0 : yystos_[state];
+ if (state == empty_state)
+ return empty_symbol;
+ else
+ return yystos_[state];
}
inline
[value], [move], [that.value])],
[[value = that.value;]])[
// that is emptied.
- that.type = empty;
+ that.type = empty_symbol;
}
inline
std::ostream& yyoutput = yyo;
YYUSE (yyoutput);
symbol_number_type yytype = yysym.type_get ();
+ // Avoid a (spurious) G++ 4.8 warning about "array subscript is
+ // below array bounds".
+ if (yysym.empty ())
+ std::abort ();
yyo << (yytype < yyntokens_ ? "token" : "nterm")
<< ' ' << yytname_[yytype] << " ("]b4_locations_if([
<< yysym.location << ": "])[;
int yynerrs_ = 0;
int yyerrstatus_ = 0;
- /// Whether yyla contains a lookahead.
- bool yyempty = true;
-
/// The lookahead symbol.
symbol_type yyla;]b4_locations_if([[
goto yydefault;
// Read a lookahead token.
- if (yyempty)
+ if (yyla.empty ())
{
YYCDEBUG << "Reading a token: ";
try
error (yyexc);
goto yyerrlab1;
}
- yyempty = false;
}
YY_SYMBOL_PRINT ("Next token is", yyla);
goto yyreduce;
}
- // Discard the token being shifted.
- yyempty = true;
-
// Count tokens shifted since error; after three, turn off error status.
if (yyerrstatus_)
--yyerrstatus_;
{
++yynerrs_;
error (]b4_join(b4_locations_if([yyla.location]),
- [[yysyntax_error_ (yystack_[0].state,
- yyempty ? yyempty_ : yyla.type_get ())]])[);
+ [[yysyntax_error_ (yystack_[0].state, yyla)]])[);
}
]b4_locations_if([[
// Return failure if at end of input.
if (yyla.type_get () == yyeof_)
YYABORT;
- else if (!yyempty)
+ else if (!yyla.empty ())
{
yy_destroy_ ("Error: discarding", yyla);
- yyempty = true;
+ yyla.clear ();
}
}
goto yyreturn;
yyreturn:
- if (!yyempty)
+ if (!yyla.empty ())
yy_destroy_ ("Cleanup: discarding lookahead", yyla);
/* Do not reclaim the symbols of the rule whose action triggered
<< std::endl;
// Do not try to display the values of the reclaimed symbols,
// as their printer might throw an exception.
- if (!yyempty)
+ if (!yyla.empty ())
yy_destroy_ (YY_NULLPTR, yyla);
while (1 < yystack_.size ())
// Generate an error message.
std::string
]b4_parser_class_name[::yysyntax_error_ (]dnl
-b4_error_verbose_if([state_type yystate, symbol_number_type yytoken],
- [state_type, symbol_number_type])[) const
+b4_error_verbose_if([state_type yystate, const symbol_type& yyla],
+ [state_type, const symbol_type&])[) const
{]b4_error_verbose_if([[
// Number of reported tokens (one for the "unexpected", one per
// "expected").
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 yytoken) is
+ - The only way there can be no lookahead present (in yyla) 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
token that will not be accepted due to an error action in a
later state.
*/
- if (yytoken != yyempty_)
+ if (!yyla.empty ())
{
+ int yytoken = yyla.type_get ();
yyarg[yycount++] = yytname_[yytoken];
int yyn = yypact_[yystate];
if (!yy_pact_value_is_default_ (yyn))
projects / bison.git / blobdiff