maint: Valgrind on OS X.

[bison.git] / data / lalr1.cc

diff --git a/data/lalr1.cc b/data/lalr1.cc
index 8affc736095c4caa4c6a3feb14b466788761b890..17a8f22c032ac8fadda107f5bee7bf0aba4e27c3 100644 (file)
--- a/data/lalr1.cc
+++ b/data/lalr1.cc
@@ -1,133 +1,84 @@
-m4_divert(-1)
-

 # C++ skeleton for Bison
 
 # C++ skeleton for Bison
 

-# Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
+# Copyright (C) 2002-2012 Free Software Foundation, Inc.

 
 

-# This program is free software; you can redistribute it and/or modify
+# 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
 # it under the terms of the GNU General Public License as published by

-# the Free Software Foundation; either version 2 of the License, or
+# the Free Software Foundation, either version 3 of the License, or

 # (at your option) any later version.
 # (at your option) any later version.

-
+#

 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.

-
+#

 # You should have received a copy of the GNU General Public License
 # You should have received a copy of the GNU General Public License

-# along with this program; if not, write to the Free Software
-# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-# 02110-1301  USA
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.

 
 m4_include(b4_pkgdatadir/[c++.m4])
 
 m4_include(b4_pkgdatadir/[c++.m4])

-# Backward compatibility.
-m4_define([b4_location_constructors])
-m4_include(b4_pkgdatadir/[location.cc])
+
+m4_define([b4_parser_class_name],
+          [b4_percent_define_get([[parser_class_name]])])
+
+# The header is mandatory.
+b4_defines_if([],
+              [b4_fatal([b4_skeleton[: using %%defines is mandatory]])])
+
+b4_percent_define_ifdef([[location_type]], [],
+  [# Backward compatibility.
+  m4_define([b4_location_constructors])
+  m4_include(b4_pkgdatadir/[location.cc])])
+m4_include(b4_pkgdatadir/[stack.hh])

 
 # We do want M4 expansion after # for CPP macros.
 m4_changecom()
 
 # We do want M4 expansion after # for CPP macros.
 m4_changecom()

-m4_divert(0)dnl
-m4_if(b4_defines_flag, 0, [],
-[@output @output_header_name@
+m4_divert_push(0)dnl
+b4_defines_if(
+[@output(b4_spec_defines_file@)@

 b4_copyright([Skeleton interface for Bison LALR(1) parsers in C++],
 b4_copyright([Skeleton interface for Bison LALR(1) parsers in C++],

-  [2002, 2003, 2004, 2005, 2006])
-dnl FIXME: This is wrong, we want computed header guards.
+             [2002-2012])

 [
 [

-/* As a special exception, you may create a larger work that contains
-   part or all of the Bison parser skeleton and distribute that work
-   under terms of your choice, so long as that work isn't itself a
-   parser generator using the skeleton or a modified version thereof
-   as a parser skeleton.  Alternatively, if you modify or redistribute
-   the parser skeleton itself, you may (at your option) remove this
-   special exception, which will cause the skeleton and the resulting
-   Bison output files to be licensed under the GNU General Public
-   License without this special exception.
-
-   This special exception was added by the Free Software Foundation in
-   version 2.2 of Bison.  */
+/**
+ ** \file ]b4_spec_defines_file[
+ ** Define the ]b4_namespace_ref[::parser class.
+ */

 
 /* C++ LALR(1) parser skeleton written by Akim Demaille.  */
 
 
 /* C++ LALR(1) parser skeleton written by Akim Demaille.  */
 

-#ifndef PARSER_HEADER_H
-# define PARSER_HEADER_H
+]b4_cpp_guard_open([b4_spec_defines_file])[
+
+]b4_percent_code_get([[requires]])[

 
 #include <string>
 #include <iostream>
 #include "stack.hh"
 
 #include <string>
 #include <iostream>
 #include "stack.hh"

+]b4_percent_define_ifdef([[location_type]], [],
+                         [[#include "location.hh"]])[

 
 

-namespace ]b4_namespace[
-{
-  class position;
-  class location;
-}
-
-/* First part of user declarations.  */
-]b4_pre_prologue[
-
-]/* Line __line__ of lalr1.cc.  */
-b4_syncline([@oline@], [@ofile@])[
-
-]dnl Include location.hh here: it might depend on headers included above.
-[#include "location.hh"
-
-/* Enabling traces.  */
-#ifndef YYDEBUG
-# define YYDEBUG ]b4_debug[
-#endif
-
-/* Enabling verbose error messages.  */
-#ifdef YYERROR_VERBOSE
-# undef YYERROR_VERBOSE
-# define YYERROR_VERBOSE 1
-#else
-# define YYERROR_VERBOSE ]b4_error_verbose[
-#endif
-
-/* Enabling the token table.  */
-#ifndef YYTOKEN_TABLE
-# define YYTOKEN_TABLE ]b4_token_table[
-#endif
+]b4_YYDEBUG_define[

 
 

-/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
-   If N is 0, then set CURRENT to the empty location which ends
-   the previous symbol: RHS[0] (always defined).  */
-
-#ifndef YYLLOC_DEFAULT
-# define YYLLOC_DEFAULT(Current, Rhs, N)               \
-do {                                                   \
-  if (N)                                               \
-    {                                                  \
-      (Current).begin = (Rhs)[1].begin;                        \
-      (Current).end   = (Rhs)[N].end;                  \
-    }                                                  \
-  else                                                 \
-    {                                                  \
-      (Current).begin = (Current).end = (Rhs)[0].end;  \
-    }                                                  \
-} while (false)
-#endif
-
-namespace ]b4_namespace[
-{
+]b4_namespace_open[

 
   /// A Bison parser.
   class ]b4_parser_class_name[
   {
   public:
     /// Symbol semantic values.
 
   /// A Bison parser.
   class ]b4_parser_class_name[
   {
   public:
     /// Symbol semantic values.

-#ifndef YYSTYPE
+#ifndef ]b4_api_PREFIX[STYPE

 ]m4_ifdef([b4_stype],
 [    union semantic_type
 ]m4_ifdef([b4_stype],
 [    union semantic_type

-b4_stype
-/* Line __line__ of lalr1.cc.  */
-b4_syncline([@oline@], [@ofile@])
-       ;],
-[    typedef int semantic_type;])[
+    {
+b4_user_stype
+    };],
+[m4_if(b4_tag_seen_flag, 0,
+[[    typedef int semantic_type;]],
+[[    typedef ]b4_api_PREFIX[STYPE semantic_type;]])])[

 #else
 #else

-    typedef YYSTYPE semantic_type;
+    typedef ]b4_api_PREFIX[STYPE semantic_type;

 #endif
     /// Symbol locations.
 #endif
     /// Symbol locations.

-    typedef ]b4_location_type[ location_type;
+    typedef ]b4_percent_define_get([[location_type]],
+                                   [[location]])[ location_type;

     /// Tokens.
     struct token
     {
     /// Tokens.
     struct token
     {


@@ -144,6 +95,7 @@ b4_syncline([@oline@], [@ofile@])
     /// \returns  0 iff parsing succeeded.
     virtual int parse ();
 
     /// \returns  0 iff parsing succeeded.
     virtual int parse ();
 

+#if ]b4_api_PREFIX[DEBUG

     /// The current debugging stream.
     std::ostream& debug_stream () const;
     /// Set the current debugging stream.
     /// The current debugging stream.
     std::ostream& debug_stream () const;
     /// Set the current debugging stream.


@@ -155,6 +107,7 @@ b4_syncline([@oline@], [@ofile@])
     debug_level_type debug_level () const;
     /// Set the current debugging level.
     void set_debug_level (debug_level_type l);
     debug_level_type debug_level () const;
     /// Set the current debugging level.
     void set_debug_level (debug_level_type l);

+#endif

 
   private:
     /// Report a syntax error.
 
   private:
     /// Report a syntax error.


@@ -164,11 +117,10 @@ b4_syncline([@oline@], [@ofile@])
 
     /// Generate an error message.
     /// \param state   the state where the error occurred.
 
     /// Generate an error message.
     /// \param state   the state where the error occurred.

-    /// \param tok     the look-ahead token.
-    virtual std::string yysyntax_error_ (int yystate]dnl
-b4_error_verbose_if([, int tok])[);
+    /// \param tok     the lookahead token.
+    virtual std::string yysyntax_error_ (int yystate, int tok);

 
 

-#if YYDEBUG
+#if ]b4_api_PREFIX[DEBUG

     /// \brief Report a symbol value on the debug stream.
     /// \param yytype       The token type.
     /// \param yyvaluep     Its semantic value.
     /// \brief Report a symbol value on the debug stream.
     /// \param yytype       The token type.
     /// \param yyvaluep     Its semantic value.


@@ -183,7 +135,7 @@ b4_error_verbose_if([, int tok])[);
     virtual void yy_symbol_print_ (int yytype,
                                   const semantic_type* yyvaluep,
                                   const location_type* yylocationp);
     virtual void yy_symbol_print_ (int yytype,
                                   const semantic_type* yyvaluep,
                                   const location_type* yylocationp);

-#endif /* ! YYDEBUG */
+#endif

 
 
     /// State numbers.
 
 
     /// State numbers.


@@ -202,6 +154,14 @@ b4_error_verbose_if([, int tok])[);
     /// The location stack.
     location_stack_type yylocation_stack_;
 
     /// The location stack.
     location_stack_type yylocation_stack_;
 

+    /// Whether the given \c yypact_ value indicates a defaulted state.
+    /// \param yyvalue   the value to check
+    static bool yy_pact_value_is_default_ (int yyvalue);
+
+    /// Whether the given \c yytable_ value indicates a syntax error.
+    /// \param yyvalue   the value to check
+    static bool yy_table_value_is_error_ (int yyvalue);
+

     /// Internal symbol numbers.
     typedef ]b4_int_type_for([b4_translate])[ token_number_type;
     /* Tables.  */
     /// Internal symbol numbers.
     typedef ]b4_int_type_for([b4_translate])[ token_number_type;
     /* Tables.  */


@@ -209,7 +169,7 @@ b4_error_verbose_if([, int tok])[);
     static const ]b4_int_type_for([b4_pact])[ yypact_[];
     static const ]b4_int_type(b4_pact_ninf, b4_pact_ninf)[ yypact_ninf_;
 
     static const ]b4_int_type_for([b4_pact])[ yypact_[];
     static const ]b4_int_type(b4_pact_ninf, b4_pact_ninf)[ yypact_ninf_;
 

-    /// For a state, default rule to reduce.
+    /// For a state, default reduction number.

     /// Unless\a  yytable_ specifies something else to do.
     /// Zero means the default is an error.
     static const ]b4_int_type_for([b4_defact])[ yydefact_[];
     /// Unless\a  yytable_ specifies something else to do.
     /// Zero means the default is an error.
     static const ]b4_int_type_for([b4_defact])[ yydefact_[];


@@ -233,19 +193,15 @@ b4_error_verbose_if([, int tok])[);
     /// For a rule, its LHS.
     static const ]b4_int_type_for([b4_r1])[ yyr1_[];
     /// For a rule, its RHS length.
     /// For a rule, its LHS.
     static const ]b4_int_type_for([b4_r1])[ yyr1_[];
     /// For a rule, its RHS length.

-    static const ]b4_int_type_for([b4_r2])[ yyr2_[];
-
-#if YYDEBUG || YYERROR_VERBOSE || YYTOKEN_TABLE
-    /// For a symbol, its name in clear.
-    static const char* const yytname_[];
-#endif
+    static const ]b4_int_type_for([b4_r2])[ yyr2_[]; ]b4_error_verbose_if([

 
 

-#if YYERROR_VERBOSE

     /// Convert the symbol name \a n to a form suitable for a diagnostic.
     /// Convert the symbol name \a n to a form suitable for a diagnostic.

-    virtual std::string yytnamerr_ (const char *n);
-#endif
+    static std::string yytnamerr_ (const char *n);])[

 
 

-#if YYDEBUG
+]b4_token_table_if([], [[#if ]b4_api_PREFIX[DEBUG]])[
+    /// For a symbol, its name in clear.
+    static const char* const yytname_[];
+]b4_token_table_if([[#if ]b4_api_PREFIX[DEBUG]])[

     /// A type to store symbol numbers and -1.
     typedef ]b4_int_type_for([b4_rhs])[ rhs_number_type;
     /// A `-1'-separated list of the rules' RHS.
     /// A type to store symbol numbers and -1.
     typedef ]b4_int_type_for([b4_rhs])[ rhs_number_type;
     /// A `-1'-separated list of the rules' RHS.


@@ -260,6 +216,10 @@ b4_error_verbose_if([, int tok])[);
     virtual void yy_reduce_print_ (int r);
     /// Print the state stack on the debug stream.
     virtual void yystack_print_ ();
     virtual void yy_reduce_print_ (int r);
     /// Print the state stack on the debug stream.
     virtual void yystack_print_ ();

+
+    /* Debugging.  */
+    int yydebug_;
+    std::ostream* yycdebug_;

 #endif
 
     /// Convert a scanner token number \a t to a symbol number.
 #endif
 
     /// Convert a scanner token number \a t to a symbol number.


@@ -290,58 +250,44 @@ b4_error_verbose_if([, int tok])[);
     static const int yyntokens_;
     static const unsigned int yyuser_token_number_max_;
     static const token_number_type yyundef_token_;
     static const int yyntokens_;
     static const unsigned int yyuser_token_number_max_;
     static const token_number_type yyundef_token_;

-
-    /* Debugging.  */
-    int yydebug_;
-    std::ostream* yycdebug_;
-

 ]b4_parse_param_vars[
   };
 ]b4_parse_param_vars[
   };

-}
+]b4_namespace_close[

 
 

-]m4_ifset([b4_global_tokens_and_yystype],
+]b4_percent_define_flag_if([[global_tokens_and_yystype]],

 [b4_token_defines(b4_tokens)
 
 [b4_token_defines(b4_tokens)
 

-#ifndef YYSTYPE
+#ifndef ]b4_api_PREFIX[STYPE

  /* Redirection for backward compatibility.  */
  /* Redirection for backward compatibility.  */

-# define YYSTYPE b4_namespace::b4_parser_class_name::semantic_type
+# define ]b4_api_PREFIX[STYPE b4_namespace_ref::b4_parser_class_name::semantic_type

 #endif
 ])[
 #endif
 ])[

-#endif /* ! defined PARSER_HEADER_H */]
+]b4_percent_code_get([[provides]])[
+]b4_cpp_guard_close([b4_spec_defines_file])

 ])dnl
 ])dnl

-@output @output_parser_name@
+@output(b4_parser_file_name@)@

 b4_copyright([Skeleton implementation for Bison LALR(1) parsers in C++],
 b4_copyright([Skeleton implementation for Bison LALR(1) parsers in C++],

-  [2002, 2003, 2004, 2005, 2006])
-[
-/* As a special exception, you may create a larger work that contains
-   part or all of the Bison parser skeleton and distribute that work
-   under terms of your choice, so long as that work isn't itself a
-   parser generator using the skeleton or a modified version thereof
-   as a parser skeleton.  Alternatively, if you modify or redistribute
-   the parser skeleton itself, you may (at your option) remove this
-   special exception, which will cause the skeleton and the resulting
-   Bison output files to be licensed under the GNU General Public
-   License without this special exception.
-
-   This special exception was added by the Free Software Foundation in
-   version 2.2 of Bison.  */
-]
+             [2002-2012])
+b4_percent_code_get([[top]])[]dnl

 m4_if(b4_prefix, [yy], [],
 [
 // Take the name prefix into account.
 m4_if(b4_prefix, [yy], [],
 [
 // Take the name prefix into account.

-#define yylex   b4_prefix[]lex])
-m4_if(b4_defines_flag, 0, [],
-[
-#include @output_header_name@])[
+#define yylex   b4_prefix[]lex])[
+
+/* First part of user declarations.  */
+]b4_user_pre_prologue[
+
+]b4_defines_if([[
+#include "@basename(]b4_spec_defines_file[@)"]])[

 
 /* User implementation prologue.  */
 
 /* User implementation prologue.  */

-]b4_post_prologue[
+]b4_user_post_prologue[
+]b4_percent_code_get[

 
 

-]/* Line __line__ of lalr1.cc.  */
-b4_syncline([@oline@], [@ofile@])[
+]b4_null_define[

 
 #ifndef YY_
 
 #ifndef YY_

-# if YYENABLE_NLS
+# if defined YYENABLE_NLS && YYENABLE_NLS

 #  if ENABLE_NLS
 #   include <libintl.h> /* FIXME: INFRINGES ON USER NAME SPACE */
 #   define YY_(msgid) dgettext ("bison-runtime", msgid)
 #  if ENABLE_NLS
 #   include <libintl.h> /* FIXME: INFRINGES ON USER NAME SPACE */
 #   define YY_(msgid) dgettext ("bison-runtime", msgid)


@@ -352,16 +298,17 @@ b4_syncline([@oline@], [@ofile@])[
 # endif
 #endif
 
 # endif
 #endif
 

+#define YYRHSLOC(Rhs, K) ((Rhs)[K])
+]b4_yylloc_default_define[
+

 /* Suppress unused-variable warnings by "using" E.  */
 #define YYUSE(e) ((void) (e))
 
 /* Suppress unused-variable warnings by "using" E.  */
 #define YYUSE(e) ((void) (e))
 

-/* A pseudo ostream that takes yydebug_ into account.  */
-# define YYCDEBUG                                                      \
-  for (bool yydebugcond_ = yydebug_; yydebugcond_; yydebugcond_ = false)       \
-    (*yycdebug_)
-

 /* Enable debugging if requested.  */
 /* Enable debugging if requested.  */

-#if YYDEBUG
+#if ]b4_api_PREFIX[DEBUG
+
+/* A pseudo ostream that takes yydebug_ into account.  */
+# define YYCDEBUG if (yydebug_) (*yycdebug_)

 
 # define YY_SYMBOL_PRINT(Title, Type, Value, Location) \
 do {                                                   \
 
 # define YY_SYMBOL_PRINT(Title, Type, Value, Location) \
 do {                                                   \


@@ -385,21 +332,24 @@ do {                                      \
     yystack_print_ ();                 \
 } while (false)
 
     yystack_print_ ();                 \
 } while (false)
 

-#else /* !YYDEBUG */
+#else /* !]b4_api_PREFIX[DEBUG */

 
 

+# define YYCDEBUG if (false) std::cerr

 # define YY_SYMBOL_PRINT(Title, Type, Value, Location)
 # define YY_REDUCE_PRINT(Rule)
 # define YY_STACK_PRINT()
 
 # define YY_SYMBOL_PRINT(Title, Type, Value, Location)
 # define YY_REDUCE_PRINT(Rule)
 # define YY_STACK_PRINT()
 

-#endif /* !YYDEBUG */
+#endif /* !]b4_api_PREFIX[DEBUG */
+
+#define yyerrok                (yyerrstatus_ = 0)
+#define yyclearin      (yychar = yyempty_)

 
 #define YYACCEPT       goto yyacceptlab
 #define YYABORT                goto yyabortlab
 #define YYERROR                goto yyerrorlab
 
 #define YYACCEPT       goto yyacceptlab
 #define YYABORT                goto yyabortlab
 #define YYERROR                goto yyerrorlab

+#define YYRECOVERING()  (!!yyerrstatus_)

 
 

-namespace ]b4_namespace[
-{
-#if YYERROR_VERBOSE
+]b4_namespace_open[]b4_error_verbose_if([[

 
   /* Return YYSTR after stripping away unnecessary quotes and
      backslashes, so that it's suitable for yyerror.  The heuristic is
 
   /* Return YYSTR after stripping away unnecessary quotes and
      backslashes, so that it's suitable for yyerror.  The heuristic is


@@ -437,13 +387,15 @@ namespace ]b4_namespace[
 
     return yystr;
   }
 
     return yystr;
   }

-
-#endif
+]])[

 
   /// Build a parser object.
 
   /// Build a parser object.

-  ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)
-    : yydebug_ (false),
-      yycdebug_ (&std::cerr)]b4_parse_param_cons[
+  ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [
+    :])[
+#if ]b4_api_PREFIX[DEBUG
+    ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
+      yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
+#endif]b4_parse_param_cons[

   {
   }
 
   {
   }
 


@@ -451,7 +403,7 @@ namespace ]b4_namespace[
   {
   }
 
   {
   }
 

-#if YYDEBUG
+#if ]b4_api_PREFIX[DEBUG

   /*--------------------------------.
   | Print this symbol on YYOUTPUT.  |
   `--------------------------------*/
   /*--------------------------------.
   | Print this symbol on YYOUTPUT.  |
   `--------------------------------*/


@@ -462,6 +414,9 @@ namespace ]b4_namespace[
   {
     YYUSE (yylocationp);
     YYUSE (yyvaluep);
   {
     YYUSE (yylocationp);
     YYUSE (yyvaluep);

+    std::ostream& yyo = debug_stream ();
+    std::ostream& yyoutput = yyo;
+    YYUSE (yyoutput);

     switch (yytype)
       {
   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
     switch (yytype)
       {
   ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl


@@ -481,7 +436,7 @@ namespace ]b4_namespace[
     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
     *yycdebug_ << ')';
   }
     yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
     *yycdebug_ << ')';
   }

-#endif /* ! YYDEBUG */
+#endif

 
   void
   ]b4_parser_class_name[::yydestruct_ (const char* yymsg,
 
   void
   ]b4_parser_class_name[::yydestruct_ (const char* yymsg,


@@ -509,6 +464,7 @@ namespace ]b4_namespace[
     yylocation_stack_.pop (n);
   }
 
     yylocation_stack_.pop (n);
   }
 

+#if ]b4_api_PREFIX[DEBUG

   std::ostream&
   ]b4_parser_class_name[::debug_stream () const
   {
   std::ostream&
   ]b4_parser_class_name[::debug_stream () const
   {


@@ -533,12 +489,24 @@ namespace ]b4_namespace[
   {
     yydebug_ = l;
   }
   {
     yydebug_ = l;
   }

+#endif
+
+  inline bool
+  ]b4_parser_class_name[::yy_pact_value_is_default_ (int yyvalue)
+  {
+    return yyvalue == yypact_ninf_;
+  }

 
 

+  inline bool
+  ]b4_parser_class_name[::yy_table_value_is_error_ (int yyvalue)
+  {
+    return yyvalue == yytable_ninf_;
+  }

 
   int
   ]b4_parser_class_name[::parse ()
   {
 
   int
   ]b4_parser_class_name[::parse ()
   {

-    /// Look-ahead and look-ahead in internal form.
+    /// Lookahead and lookahead in internal form.

     int yychar = yyempty_;
     int yytoken = 0;
 
     int yychar = yyempty_;
     int yytoken = 0;
 


@@ -551,12 +519,12 @@ namespace ]b4_namespace[
     int yynerrs_ = 0;
     int yyerrstatus_ = 0;
 
     int yynerrs_ = 0;
     int yyerrstatus_ = 0;
 

-    /// Semantic value of the look-ahead.
+    /// Semantic value of the lookahead.

     semantic_type yylval;
     semantic_type yylval;

-    /// Location of the look-ahead.
+    /// Location of the lookahead.

     location_type yylloc;
     /// The locations where the error started and ended.
     location_type yylloc;
     /// The locations where the error started and ended.

-    location yyerror_range[2];
+    location_type yyerror_range[3];

 
     /// $$.
     semantic_type yyval;
 
     /// $$.
     semantic_type yyval;


@@ -571,11 +539,9 @@ namespace ]b4_namespace[
 m4_pushdef([b4_at_dollar],     [yylloc])dnl
 m4_pushdef([b4_dollar_dollar], [yylval])dnl
     /* User initialization code.  */
 m4_pushdef([b4_at_dollar],     [yylloc])dnl
 m4_pushdef([b4_dollar_dollar], [yylval])dnl
     /* User initialization code.  */

-    b4_initial_action
+    b4_user_initial_action

 m4_popdef([b4_dollar_dollar])dnl
 m4_popdef([b4_dollar_dollar])dnl

-m4_popdef([b4_at_dollar])dnl
-  /* Line __line__ of yacc.c.  */
-b4_syncline([@oline@], [@ofile@])])dnl
+m4_popdef([b4_at_dollar])])dnl

 
   [  /* Initialize the stacks.  The initial state will be pushed in
        yynewstate, since the latter expects the semantical and the
 
   [  /* Initialize the stacks.  The initial state will be pushed in
        yynewstate, since the latter expects the semantical and the


@@ -591,23 +557,28 @@ b4_syncline([@oline@], [@ofile@])])dnl
   yynewstate:
     yystate_stack_.push (yystate);
     YYCDEBUG << "Entering state " << yystate << std::endl;
   yynewstate:
     yystate_stack_.push (yystate);
     YYCDEBUG << "Entering state " << yystate << std::endl;

+
+    /* Accept?  */
+    if (yystate == yyfinal_)
+      goto yyacceptlab;
+

     goto yybackup;
 
     /* Backup.  */
   yybackup:
 
     goto yybackup;
 
     /* Backup.  */
   yybackup:
 

-    /* Try to take a decision without look-ahead.  */
+    /* Try to take a decision without lookahead.  */

     yyn = yypact_[yystate];
     yyn = yypact_[yystate];

-    if (yyn == yypact_ninf_)
+    if (yy_pact_value_is_default_ (yyn))

       goto yydefault;
 
       goto yydefault;
 

-    /* Read a look-ahead token.  */
+    /* Read a lookahead token.  */

     if (yychar == yyempty_)
       {
        YYCDEBUG << "Reading a token: ";
        yychar = ]b4_c_function_call([yylex], [int],
     if (yychar == yyempty_)
       {
        YYCDEBUG << "Reading a token: ";
        yychar = ]b4_c_function_call([yylex], [int],

-                                    [[YYSTYPE*], [&yylval]][]dnl
-b4_location_if([, [[location*], [&yylloc]]])dnl
+                                    [b4_api_PREFIX[STYPE*], [&yylval]][]dnl
+b4_locations_if([, [[location*], [&yylloc]]])dnl

 m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
       }
 
 m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
       }
 


@@ -634,22 +605,17 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
     yyn = yytable_[yyn];
     if (yyn <= 0)
       {
     yyn = yytable_[yyn];
     if (yyn <= 0)
       {

-       if (yyn == 0 || yyn == yytable_ninf_)
-       goto yyerrlab;
+       if (yy_table_value_is_error_ (yyn))
+         goto yyerrlab;

        yyn = -yyn;
        goto yyreduce;
       }
 
        yyn = -yyn;
        goto yyreduce;
       }
 

-    /* Accept?  */
-    if (yyn == yyfinal_)
-      goto yyacceptlab;
-
-    /* Shift the look-ahead token.  */
+    /* Shift the lookahead token.  */

     YY_SYMBOL_PRINT ("Shifting", yytoken, &yylval, &yylloc);
 
     YY_SYMBOL_PRINT ("Shifting", yytoken, &yylval, &yylloc);
 

-    /* Discard the token being shifted unless it is eof.  */
-    if (yychar != yyeof_)
-      yychar = yyempty_;
+    /* Discard the token being shifted.  */
+    yychar = yyempty_;

 
     yysemantic_stack_.push (yylval);
     yylocation_stack_.push (yylloc);
 
     yysemantic_stack_.push (yylval);
     yylocation_stack_.push (yylloc);


@@ -694,11 +660,21 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
     YY_REDUCE_PRINT (yyn);
     switch (yyn)
       {
     YY_REDUCE_PRINT (yyn);
     switch (yyn)
       {

-       ]b4_actions
-    /* Line __line__ of lalr1.cc.  */
-b4_syncline([@oline@], [@ofile@])[
-       default: break;
+       ]b4_user_actions[
+       default:
+          break;

       }
       }

+    /* User semantic actions sometimes alter yychar, and that requires
+       that yytoken be updated with the new translation.  We take the
+       approach of translating immediately before every use of yytoken.
+       One alternative is translating here after every semantic action,
+       but that translation would be missed if the semantic action
+       invokes YYABORT, YYACCEPT, or YYERROR immediately after altering
+       yychar.  In the case of YYABORT or YYACCEPT, an incorrect
+       destructor might then be invoked immediately.  In the case of
+       YYERROR, subsequent parser actions might lead to an incorrect
+       destructor call or verbose syntax error message before the
+       lookahead is translated.  */

     YY_SYMBOL_PRINT ("-> $$ =", yyr1_[yyn], &yyval, &yyloc);
 
     yypop_ (yylen);
     YY_SYMBOL_PRINT ("-> $$ =", yyr1_[yyn], &yyval, &yyloc);
 
     yypop_ (yylen);


@@ -722,18 +698,23 @@ b4_syncline([@oline@], [@ofile@])[
   | yyerrlab -- here on detecting error |
   `------------------------------------*/
   yyerrlab:
   | yyerrlab -- here on detecting error |
   `------------------------------------*/
   yyerrlab:

+    /* Make sure we have latest lookahead translation.  See comments at
+       user semantic actions for why this is necessary.  */
+    yytoken = yytranslate_ (yychar);
+

     /* If not already recovering from an error, report this error.  */
     if (!yyerrstatus_)
       {
        ++yynerrs_;
     /* If not already recovering from an error, report this error.  */
     if (!yyerrstatus_)
       {
        ++yynerrs_;

-       error (yylloc, yysyntax_error_ (yystate]dnl
-b4_error_verbose_if([, yytoken])[));
+       if (yychar == yyempty_)
+         yytoken = yyempty_;
+       error (yylloc, yysyntax_error_ (yystate, yytoken));

       }
 
       }
 

-    yyerror_range[0] = yylloc;
+    yyerror_range[1] = yylloc;

     if (yyerrstatus_ == 3)
       {
     if (yyerrstatus_ == 3)
       {

-       /* If just tried and failed to reuse look-ahead token after an
+       /* If just tried and failed to reuse lookahead token after an

         error, discard it.  */
 
        if (yychar <= yyeof_)
         error, discard it.  */
 
        if (yychar <= yyeof_)


@@ -749,7 +730,7 @@ b4_error_verbose_if([, yytoken])[));
          }
       }
 
          }
       }
 

-    /* Else will try to reuse look-ahead token after shifting the error
+    /* Else will try to reuse lookahead token after shifting the error

        token.  */
     goto yyerrlab1;
 
        token.  */
     goto yyerrlab1;
 


@@ -765,7 +746,7 @@ b4_error_verbose_if([, yytoken])[));
     if (false)
       goto yyerrorlab;
 
     if (false)
       goto yyerrorlab;
 

-    yyerror_range[0] = yylocation_stack_[yylen - 1];
+    yyerror_range[1] = yylocation_stack_[yylen - 1];

     /* Do not reclaim the symbols of the rule which action triggered
        this YYERROR.  */
     yypop_ (yylen);
     /* Do not reclaim the symbols of the rule which action triggered
        this YYERROR.  */
     yypop_ (yylen);


@@ -782,7 +763,7 @@ b4_error_verbose_if([, yytoken])[));
     for (;;)
       {
        yyn = yypact_[yystate];
     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_)
        {
          yyn += yyterror_;
          if (0 <= yyn && yyn <= yylast_ && yycheck_[yyn] == yyterror_)


@@ -797,7 +778,7 @@ b4_error_verbose_if([, yytoken])[));
        if (yystate_stack_.height () == 1)
        YYABORT;
 
        if (yystate_stack_.height () == 1)
        YYABORT;
 

-       yyerror_range[0] = yylocation_stack_[0];
+       yyerror_range[1] = yylocation_stack_[0];

        yydestruct_ ("Error: popping",
                     yystos_[yystate],
                     &yysemantic_stack_[0], &yylocation_stack_[0]);
        yydestruct_ ("Error: popping",
                     yystos_[yystate],
                     &yysemantic_stack_[0], &yylocation_stack_[0]);


@@ -806,19 +787,16 @@ b4_error_verbose_if([, yytoken])[));
        YY_STACK_PRINT ();
       }
 
        YY_STACK_PRINT ();
       }
 

-    if (yyn == yyfinal_)
-      goto yyacceptlab;
-
-    yyerror_range[1] = yylloc;
+    yyerror_range[2] = yylloc;

     // Using YYLLOC is tempting, but would change the location of
     // Using YYLLOC is tempting, but would change the location of

-    // the look-ahead.  YYLOC is available though.
-    YYLLOC_DEFAULT (yyloc, (yyerror_range - 1), 2);
+    // the lookahead.  YYLOC is available though.
+    YYLLOC_DEFAULT (yyloc, yyerror_range, 2);

     yysemantic_stack_.push (yylval);
     yylocation_stack_.push (yyloc);
 
     /* Shift the error token.  */
     YY_SYMBOL_PRINT ("Shifting", yystos_[yyn],
     yysemantic_stack_.push (yylval);
     yylocation_stack_.push (yyloc);
 
     /* Shift the error token.  */
     YY_SYMBOL_PRINT ("Shifting", yystos_[yyn],

-                  &yysemantic_stack_[0], &yylocation_stack_[0]);
+                    &yysemantic_stack_[0], &yylocation_stack_[0]);

 
     yystate = yyn;
     goto yynewstate;
 
     yystate = yyn;
     goto yynewstate;


@@ -834,8 +812,14 @@ b4_error_verbose_if([, yytoken])[));
     goto yyreturn;
 
   yyreturn:
     goto yyreturn;
 
   yyreturn:

-    if (yychar != yyeof_ && yychar != yyempty_)
-      yydestruct_ ("Cleanup: discarding lookahead", yytoken, &yylval, &yylloc);
+    if (yychar != yyempty_)
+      {
+        /* Make sure we have latest lookahead translation.  See comments
+           at user semantic actions for why this is necessary.  */
+        yytoken = yytranslate_ (yychar);
+        yydestruct_ ("Cleanup: discarding lookahead", yytoken, &yylval,
+                     &yylloc);
+      }

 
     /* Do not reclaim the symbols of the rule which action triggered
        this YYABORT or YYACCEPT.  */
 
     /* Do not reclaim the symbols of the rule which action triggered
        this YYABORT or YYACCEPT.  */


@@ -854,52 +838,100 @@ b4_error_verbose_if([, yytoken])[));
 
   // Generate an error message.
   std::string
 
   // Generate an error message.
   std::string

-  ]b4_parser_class_name[::yysyntax_error_ (int yystate]dnl
-b4_error_verbose_if([, int tok])[)
-  {
-    std::string res;
-    YYUSE (yystate);
-#if YYERROR_VERBOSE
-    int yyn = yypact_[yystate];
-    if (yypact_ninf_ < yyn && yyn < yylast_)
+  ]b4_parser_class_name[::yysyntax_error_ (]dnl
+b4_error_verbose_if([int yystate, int yytoken],
+                    [int, int])[)
+  {]b4_error_verbose_if([[
+    std::string yyres;
+    // Number of reported tokens (one for the "unexpected", one per
+    // "expected").
+    size_t yycount = 0;
+    // Its maximum.
+    enum { YYERROR_VERBOSE_ARGS_MAXIMUM = 5 };
+    // Arguments of yyformat.
+    char const *yyarg[YYERROR_VERBOSE_ARGS_MAXIMUM];
+
+    /* There are many possibilities here to consider:
+       - 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 yytoken) 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.
+       - 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 (yytoken != yyempty_)

       {
       {

-       /* 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;
-       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.  It should work like yacc.c does it.
-       // That is, first build a string that looks like this:
-       // "syntax error, unexpected %s or %s or %s"
-       // Then, invoke YY_ on this string.
-       // Finally, use the string as a format to output
-       // yytname_[tok], etc.
-       // Until this gets fixed, this message appears in English only.
-       res = "syntax error, unexpected ";
-       res += yytnamerr_ (yytname_[tok]);
-       if (count < 5)
-         {
-           count = 0;
-           for (int x = yyxbegin; x < yyxend; ++x)
-             if (yycheck_[x + yyn] == x && x != yyterror_)
-               {
-                 res += (!count++) ? ", expecting " : " or ";
-                 res += yytnamerr_ (yytname_[x]);
-               }
-         }
+        yyarg[yycount++] = yytname_[yytoken];
+        int yyn = yypact_[yystate];
+        if (!yy_pact_value_is_default_ (yyn))
+          {
+            /* 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_;
+            for (int yyx = yyxbegin; yyx < yyxend; ++yyx)
+              if (yycheck_[yyx + yyn] == yyx && yyx != yyterror_
+                  && !yy_table_value_is_error_ (yytable_[yyx + yyn]))
+                {
+                  if (yycount == YYERROR_VERBOSE_ARGS_MAXIMUM)
+                    {
+                      yycount = 1;
+                      break;
+                    }
+                  else
+                    yyarg[yycount++] = yytname_[yyx];
+                }
+          }

       }
       }

-    else
-#endif
-      res = YY_("syntax error");
-    return res;
+
+    char const* yyformat = YY_NULL;
+    switch (yycount)
+      {
+#define YYCASE_(N, S)                         \
+        case N:                               \
+          yyformat = S;                       \
+        break
+        YYCASE_(0, YY_("syntax error"));
+        YYCASE_(1, YY_("syntax error, unexpected %s"));
+        YYCASE_(2, YY_("syntax error, unexpected %s, expecting %s"));
+        YYCASE_(3, YY_("syntax error, unexpected %s, expecting %s or %s"));
+        YYCASE_(4, YY_("syntax error, unexpected %s, expecting %s or %s or %s"));
+        YYCASE_(5, YY_("syntax error, unexpected %s, expecting %s or %s or %s or %s"));
+#undef YYCASE_
+      }
+
+    // Argument number.
+    size_t yyi = 0;
+    for (char const* yyp = yyformat; *yyp; ++yyp)
+      if (yyp[0] == '%' && yyp[1] == 's' && yyi < yycount)
+        {
+          yyres += yytnamerr_ (yyarg[yyi++]);
+          ++yyp;
+        }
+      else
+        yyres += *yyp;
+    return yyres;]], [[
+    return YY_("syntax error");]])[

   }
 
 
   }
 
 


@@ -912,9 +944,9 @@ b4_error_verbose_if([, int tok])[)
     ]b4_pact[
   };
 
     ]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.  */
+  /* YYDEFACT[S] -- default reduction number in state S.  Performed when
+     YYTABLE doesn't specify something else to do.  Zero means the
+     default is an error.  */

   const ]b4_int_type_for([b4_defact])[
   ]b4_parser_class_name[::yydefact_[] =
   {
   const ]b4_int_type_for([b4_defact])[
   ]b4_parser_class_name[::yydefact_[] =
   {


@@ -937,7 +969,7 @@ b4_error_verbose_if([, int tok])[)
 
   /* YYTABLE[YYPACT[STATE-NUM]].  What to do in state STATE-NUM.  If
      positive, shift that token.  If negative, reduce the rule which
 
   /* 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.  */
+     number is the opposite.  If YYTABLE_NINF_, syntax error.  */

   const ]b4_int_type(b4_table_ninf, b4_table_ninf) b4_parser_class_name::yytable_ninf_ = b4_table_ninf[;
   const ]b4_int_type_for([b4_table])[
   ]b4_parser_class_name[::yytable_[] =
   const ]b4_int_type(b4_table_ninf, b4_table_ninf) b4_parser_class_name::yytable_ninf_ = b4_table_ninf[;
   const ]b4_int_type_for([b4_table])[
   ]b4_parser_class_name[::yytable_[] =


@@ -960,7 +992,7 @@ b4_error_verbose_if([, int tok])[)
     ]b4_stos[
   };
 
     ]b4_stos[
   };
 

-#if YYDEBUG
+#if ]b4_api_PREFIX[DEBUG

   /* TOKEN_NUMBER_[YYLEX-NUM] -- Internal symbol number corresponding
      to YYLEX-NUM.  */
   const ]b4_int_type_for([b4_toknum])[
   /* TOKEN_NUMBER_[YYLEX-NUM] -- Internal symbol number corresponding
      to YYLEX-NUM.  */
   const ]b4_int_type_for([b4_toknum])[


@@ -984,7 +1016,7 @@ b4_error_verbose_if([, int tok])[)
     ]b4_r2[
   };
 
     ]b4_r2[
   };
 

-#if YYDEBUG || YYERROR_VERBOSE || YYTOKEN_TABLE
+]b4_token_table_if([], [[#if ]b4_api_PREFIX[DEBUG]])[

   /* YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
      First, the terminals, then, starting at \a yyntokens_, nonterminals.  */
   const char*
   /* YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
      First, the terminals, then, starting at \a yyntokens_, nonterminals.  */
   const char*


@@ -992,9 +1024,8 @@ b4_error_verbose_if([, int tok])[)
   {
     ]b4_tname[
   };
   {
     ]b4_tname[
   };

-#endif

 
 

-#if YYDEBUG
+]b4_token_table_if([[#if ]b4_api_PREFIX[DEBUG]])[

   /* YYRHS -- A `-1'-separated list of the rules' RHS.  */
   const ]b4_parser_class_name[::rhs_number_type
   ]b4_parser_class_name[::yyrhs_[] =
   /* YYRHS -- A `-1'-separated list of the rules' RHS.  */
   const ]b4_parser_class_name[::rhs_number_type
   ]b4_parser_class_name[::yyrhs_[] =


@@ -1036,7 +1067,7 @@ b4_error_verbose_if([, int tok])[)
     int yynrhs = yyr2_[yyrule];
     /* Print the symbols being reduced, and their result.  */
     *yycdebug_ << "Reducing stack by rule " << yyrule - 1
     int yynrhs = yyr2_[yyrule];
     /* Print the symbols being reduced, and their result.  */
     *yycdebug_ << "Reducing stack by rule " << yyrule - 1

-              << " (line " << yylno << "), ";
+              << " (line " << yylno << "):" << std::endl;

     /* The symbols being reduced.  */
     for (int yyi = 0; yyi < yynrhs; yyi++)
       YY_SYMBOL_PRINT ("   $" << yyi + 1 << " =",
     /* The symbols being reduced.  */
     for (int yyi = 0; yyi < yynrhs; yyi++)
       YY_SYMBOL_PRINT ("   $" << yyi + 1 << " =",


@@ -1044,7 +1075,7 @@ b4_error_verbose_if([, int tok])[)
                       &]b4_rhs_value(yynrhs, yyi + 1)[,
                       &]b4_rhs_location(yynrhs, yyi + 1)[);
   }
                       &]b4_rhs_value(yynrhs, yyi + 1)[,
                       &]b4_rhs_location(yynrhs, yyi + 1)[);
   }

-#endif // YYDEBUG
+#endif // ]b4_api_PREFIX[DEBUG

 
   /* YYTRANSLATE(YYLEX) -- Bison symbol number corresponding to YYLEX.  */
   ]b4_parser_class_name[::token_number_type
 
   /* YYTRANSLATE(YYLEX) -- Bison symbol number corresponding to YYLEX.  */
   ]b4_parser_class_name[::token_number_type


@@ -1074,120 +1105,6 @@ b4_error_verbose_if([, int tok])[)
   const unsigned int ]b4_parser_class_name[::yyuser_token_number_max_ = ]b4_user_token_number_max[;
   const ]b4_parser_class_name[::token_number_type ]b4_parser_class_name[::yyundef_token_ = ]b4_undef_token_number[;
 
   const unsigned int ]b4_parser_class_name[::yyuser_token_number_max_ = ]b4_user_token_number_max[;
   const ]b4_parser_class_name[::token_number_type ]b4_parser_class_name[::yyundef_token_ = ]b4_undef_token_number[;
 

-} // namespace ]b4_namespace[
-
+]b4_namespace_close[

 ]b4_epilogue
 ]b4_epilogue

-dnl
-@output b4_dir_prefix[]stack.hh
-b4_copyright([Stack handling for Bison parsers in C++],
-  [2002, 2003, 2004, 2005, 2006])
-[
-/* As a special exception, you may create a larger work that contains
-   part or all of the Bison parser skeleton and distribute that work
-   under terms of your choice, so long as that work isn't itself a
-   parser generator using the skeleton or a modified version thereof
-   as a parser skeleton.  Alternatively, if you modify or redistribute
-   the parser skeleton itself, you may (at your option) remove this
-   special exception, which will cause the skeleton and the resulting
-   Bison output files to be licensed under the GNU General Public
-   License without this special exception.
-
-   This special exception was added by the Free Software Foundation in
-   version 2.2 of Bison.  */
-
-#ifndef BISON_STACK_HH
-# define BISON_STACK_HH
-
-#include <deque>
-
-namespace ]b4_namespace[
-{
-  template <class T, class S = std::deque<T> >
-  class stack
-  {
-  public:
-
-    // Hide our reversed order.
-    typedef typename S::reverse_iterator iterator;
-    typedef typename S::const_reverse_iterator const_iterator;
-
-    stack () : seq_ ()
-    {
-    }
-
-    stack (unsigned int n) : seq_ (n)
-    {
-    }
-
-    inline
-    T&
-    operator [] (unsigned int i)
-    {
-      return seq_[i];
-    }
-
-    inline
-    const T&
-    operator [] (unsigned int i) const
-    {
-      return seq_[i];
-    }
-
-    inline
-    void
-    push (const T& t)
-    {
-      seq_.push_front (t);
-    }
-
-    inline
-    void
-    pop (unsigned int n = 1)
-    {
-      for (; n; --n)
-       seq_.pop_front ();
-    }
-
-    inline
-    unsigned int
-    height () const
-    {
-      return seq_.size ();
-    }
-
-    inline const_iterator begin () const { return seq_.rbegin (); }
-    inline const_iterator end () const { return seq_.rend (); }
-
-  private:
-
-    S seq_;
-  };
-
-  /// Present a slice of the top of a stack.
-  template <class T, class S = stack<T> >
-  class slice
-  {
-  public:
-
-    slice (const S& stack,
-          unsigned int range) : stack_ (stack),
-                                range_ (range)
-    {
-    }
-
-    inline
-    const T&
-    operator [] (unsigned int i) const
-    {
-      return stack_[range_ - i];
-    }
-
-  private:
-
-    const S& stack_;
-    unsigned int range_;
-  };
-}
-
-#endif // not BISON_STACK_HH]
-m4_divert(-1)
+m4_divert_pop(0)