Simplify yysyntax_error_ use.

[bison.git] / data / lalr1.cc

diff --git a/data/lalr1.cc b/data/lalr1.cc
index 000cd0d1efee39aa44cde10fbddbfd889ae58ccb..7195c28d015a3089bb623ca3d9ce6933afa72165 100644 (file)
--- a/data/lalr1.cc
+++ b/data/lalr1.cc
@@ -1,29 +1,117 @@
-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, 2003, 2004, 2005, 2006, 2007, 2008
+# 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])
 

+# How the semantic value is extracted when using variants.
+b4_variant_if([
+  # b4_symbol_value(VAL, [TYPE])
+  # ----------------------------
+  m4_define([b4_symbol_value],
+  [m4_ifval([$2],
+            [$1.as<$2>()],
+            [$1])])
+]) # b4_variant_if
+
+
+# b4_symbol_actions(FILENAME, LINENO,
+#                   SYMBOL-TAG, SYMBOL-NUM,
+#                   SYMBOL-ACTION, SYMBOL-TYPENAME)
+# -------------------------------------------------
+# Same as in C, but using references instead of pointers.
+m4_define([b4_symbol_actions],
+[m4_pushdef([b4_dollar_dollar],
+            [b4_symbol_value([yyvalue], [$6])])dnl
+m4_pushdef([b4_at_dollar], [yylocation])dnl
+      case $4: // $3
+b4_syncline([$2], [$1])
+        $5;
+b4_syncline([@oline@], [@ofile@])
+        break;
+m4_popdef([b4_at_dollar])dnl
+m4_popdef([b4_dollar_dollar])dnl
+])
+
+
+# b4_symbol_action_(SYMBOL-TAG, SYMBOL-NUM, SYMBOL-TYPENAME)
+# ----------------------------------------------------------
+# Invoke b4_dollar_dollar(SYMBOL_TYPENAME) for each symbol.
+m4_define([b4_symbol_action_],
+[m4_ifval($3,
+[      case $2: // $1
+        b4_dollar_dollar($@);
+       break;
+])])
+
+
+# b4_symbol_variant(YYTYPE, YYVAL, ACTION)
+# ----------------------------------------
+# Run some ACTION ("build", or "destroy") on YYVAL of symbol type
+# YYTYPE.
+m4_define([b4_symbol_variant],
+[m4_pushdef([b4_dollar_dollar],
+            [$2.$3<$][3>()])dnl
+  switch ($1)
+    {
+m4_map([b4_symbol_action_], m4_defn([b4_type_names]))
+     default:
+       break;
+    }
+m4_popdef([b4_dollar_dollar])dnl
+])
+
+
+# _b4_char_sizeof_counter
+# -----------------------
+# A counter used by _b4_char_sizeof_dummy to create fresh symbols.
+m4_define([_b4_char_sizeof_counter],
+[0])
+
+# _b4_char_sizeof_dummy
+# ---------------------
+# At each call return a new C++ identifier.
+m4_define([_b4_char_sizeof_dummy],
+[m4_define([_b4_char_sizeof_counter], m4_incr(_b4_char_sizeof_counter))dnl
+dummy[]_b4_char_sizeof_counter])
+
+
+# b4_char_sizeof(SYMBOL-TAG, SYMBOL-NUM, SYMBOL-TYPENAME)
+# -------------------------------------------------------
+# To be mapped on the list of type names to produce:
+#
+#    char dummy1[sizeof(type_name_1)];
+#    char dummy2[sizeof(type_name_2)];
+#
+# for defined type names.
+# $3 is doubly-quoted, do not quote it again.
+m4_define([b4_char_sizeof],
+[m4_ifval($3,
+[
+      char _b4_char_sizeof_dummy@{sizeof($3)@}; // $1])dnl
+])
+
+
+m4_define([b4_parser_class_name],
+          [b4_percent_define_get([[parser_class_name]])])
+

 # The header is mandatory.
 b4_defines_if([],
 # The header is mandatory.
 b4_defines_if([],

-              [m4_fatal(b4_skeleton[: using %defines is mandatory])])
+              [b4_fatal([b4_skeleton[: using %%defines is mandatory]])])

 
 # Backward compatibility.
 m4_define([b4_location_constructors])
 
 # Backward compatibility.
 m4_define([b4_location_constructors])


@@ -31,11 +119,11 @@ m4_include(b4_pkgdatadir/[location.cc])
 
 # 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_divert_push(0)dnl

 b4_defines_if(
 b4_defines_if(

-[@output @output_header_name@
+[@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])
+             [2002, 2003, 2004, 2005, 2006, 2007, 2008])

 dnl FIXME: This is wrong, we want computed header guards.
 [
 /* C++ LALR(1) parser skeleton written by Akim Demaille.  */
 dnl FIXME: This is wrong, we want computed header guards.
 [
 /* C++ LALR(1) parser skeleton written by Akim Demaille.  */


@@ -43,22 +131,63 @@ dnl FIXME: This is wrong, we want computed header guards.
 #ifndef PARSER_HEADER_H
 # define PARSER_HEADER_H
 
 #ifndef PARSER_HEADER_H
 # define PARSER_HEADER_H
 

+]b4_percent_code_get([[requires]])[
+

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

-namespace ]b4_namespace[
-{
+]b4_namespace_open[

   class position;
   class location;
   class position;
   class location;

-}
+]b4_variant_if([[
+  /// A char[S] buffer to store and retrieve objects.
+  ///
+  /// Sort of a variant, but does not keep track of the nature
+  /// of the stored data, since that knowledge is available
+  /// via the current state.
+  template <size_t S>
+  struct variant
+  {
+    /// Instantiate a \a T in here.
+    template <typename T>
+    inline void
+    build()
+    {
+      new (buffer) T;
+    }
+
+    /// Destroy the stored \a T.
+    template <typename T>
+    inline void
+    destroy()
+    {
+      reinterpret_cast<T&>(buffer).~T();
+    }

 
 

-]m4_ifdef([b4_start_header],
-[[/* Copy the %start-header blocks.  */
-]b4_user_start_header])[
+    /// Accessor to a built \a T.
+    template <typename T>
+    inline T&
+    as()
+    {
+      return reinterpret_cast<T&>(buffer);
+    }

 
 

-]dnl Include location.hh here: it might depend on headers included above.
-[#include "location.hh"
+    /// Const accessor to a built \a T (for %printer).
+    template <typename T>
+    inline const T&
+    as() const
+    {
+      return reinterpret_cast<const T&>(buffer);
+    }
+
+    /// A buffer large enough to store any of the semantic values.
+    char buffer[S];
+  };
+]])[
+]b4_namespace_close[
+
+#include "location.hh"

 
 /* Enabling traces.  */
 #ifndef YYDEBUG
 
 /* Enabling traces.  */
 #ifndef YYDEBUG


@@ -97,27 +226,34 @@ do {                                                       \
 } while (false)
 #endif
 
 } while (false)
 #endif
 

-namespace ]b4_namespace[
-{
+]b4_namespace_open[

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

-    /// Symbol semantic values.

 #ifndef YYSTYPE
 #ifndef YYSTYPE

-]m4_ifdef([b4_stype],
+]b4_variant_if(
+[    /// An auxiliary type to compute the largest semantic type.
+    union union_type
+    {]m4_map([b4_char_sizeof], m4_defn([b4_type_names]))[
+    };
+
+    /// Symbol semantic values.
+    typedef variant<sizeof(union_type)> semantic_type;],
+[    /// Symbol semantic values.
+m4_ifdef([b4_stype],

 [    union semantic_type
 [    union semantic_type

-b4_user_stype
-       ;],
+    {b4_user_stype
+    };],

 [m4_if(b4_tag_seen_flag, 0,
 [[    typedef int semantic_type;]],
 [m4_if(b4_tag_seen_flag, 0,
 [[    typedef int semantic_type;]],

-[[    typedef YYSTYPE semantic_type;]])])[
+[[    typedef YYSTYPE semantic_type;]])])])[

 #else
     typedef YYSTYPE semantic_type;
 #endif
     /// Symbol locations.
 #else
     typedef YYSTYPE semantic_type;
 #endif
     /// Symbol locations.

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

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


@@ -134,6 +270,7 @@ b4_user_stype
     /// \returns  0 iff parsing succeeded.
     virtual int parse ();
 
     /// \returns  0 iff parsing succeeded.
     virtual int parse ();
 

+#if YYDEBUG

     /// 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.


@@ -145,6 +282,7 @@ b4_user_stype
     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.


@@ -161,19 +299,19 @@ b4_error_verbose_if([, int tok])[);
 #if YYDEBUG
     /// \brief Report a symbol value on the debug stream.
     /// \param yytype       The token type.
 #if YYDEBUG
     /// \brief Report a symbol value on the debug stream.
     /// \param yytype       The token type.

-    /// \param yyvaluep     Its semantic value.
-    /// \param yylocationp  Its location.
+    /// \param yyvalue      Its semantic value.
+    /// \param yylocation   Its location.

     virtual void yy_symbol_value_print_ (int yytype,
     virtual void yy_symbol_value_print_ (int yytype,

-                                        const semantic_type* yyvaluep,
-                                        const location_type* yylocationp);
+                                        const semantic_type& yyvalue,
+                                        const location_type& yylocation);

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

-    /// \param yyvaluep     Its semantic value.
-    /// \param yylocationp  Its location.
+    /// \param yyvalue      Its semantic value.
+    /// \param yylocation   Its location.

     virtual void yy_symbol_print_ (int yytype,
     virtual void yy_symbol_print_ (int yytype,

-                                  const semantic_type* yyvaluep,
-                                  const location_type* yylocationp);
-#endif /* ! YYDEBUG */
+                                  const semantic_type& yyvalue,
+                                  const location_type& yylocation);
+#endif

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


@@ -250,6 +388,10 @@ 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.


@@ -258,12 +400,17 @@ b4_error_verbose_if([, int tok])[);
     /// \brief Reclaim the memory associated to a symbol.
     /// \param yymsg        Why this token is reclaimed.
     /// \param yytype       The symbol type.
     /// \brief Reclaim the memory associated to a symbol.
     /// \param yymsg        Why this token is reclaimed.
     /// \param yytype       The symbol type.

-    /// \param yyvaluep     Its semantic value.
-    /// \param yylocationp  Its location.
+    /// \param yyvalue      Its semantic value.
+    /// \param yylocation   Its location.

     inline void yydestruct_ (const char* yymsg,
                             int yytype,
     inline void yydestruct_ (const char* yymsg,
                             int yytype,

-                            semantic_type* yyvaluep,
-                            location_type* yylocationp);
+                            semantic_type& yyvalue,
+                            location_type& yylocation);
+
+    /// Push a new state on the stack.
+    /// \warning the contents of \a v is stolen.
+    inline void yypush_ (state_type s,
+                         semantic_type& v, const location_type& l);

 
     /// Pop \a n symbols the three stacks.
     inline void yypop_ (unsigned int n = 1);
 
     /// Pop \a n symbols the three stacks.
     inline void yypop_ (unsigned int n = 1);


@@ -280,47 +427,42 @@ 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)
 
 #ifndef YYSTYPE
  /* Redirection for backward compatibility.  */
 [b4_token_defines(b4_tokens)
 
 #ifndef YYSTYPE
  /* Redirection for backward compatibility.  */

-# define YYSTYPE b4_namespace::b4_parser_class_name::semantic_type
+# define YYSTYPE b4_namespace_ref::b4_parser_class_name::semantic_type

 #endif
 ])
 #endif
 ])

-m4_ifdef([b4_end_header],
-[[/* Copy the %end-header blocks.  */
-]b4_end_header])[]dnl
+b4_percent_code_get([[provides]])[]dnl

 
 [#endif /* ! defined PARSER_HEADER_H */]
 ])dnl
 
 [#endif /* ! defined PARSER_HEADER_H */]
 ])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])
+             [2002, 2003, 2004, 2005, 2006, 2007, 2008])
+b4_percent_code_get([[top]])[]dnl

 m4_if(b4_prefix, [yy], [],
 [
 // Take the name prefix into account.
 #define yylex   b4_prefix[]lex])[
 
 /* First part of user declarations.  */
 m4_if(b4_prefix, [yy], [],
 [
 // Take the name prefix into account.
 #define yylex   b4_prefix[]lex])[
 
 /* First part of user declarations.  */

-]b4_pre_prologue
+]b4_user_pre_prologue

 
 

-b4_defines_if([
-#include @output_header_name@])[
+b4_defines_if([[
+#include "@basename(]b4_spec_defines_file[@)"]])[

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

-]b4_user_post_prologue[
+]b4_user_post_prologue
+b4_percent_code_get[]dnl

 
 

-#ifndef YY_
+[#ifndef YY_

 # if YYENABLE_NLS
 #  if ENABLE_NLS
 #   include <libintl.h> /* FIXME: INFRINGES ON USER NAME SPACE */
 # if YYENABLE_NLS
 #  if ENABLE_NLS
 #   include <libintl.h> /* FIXME: INFRINGES ON USER NAME SPACE */


@@ -335,14 +477,12 @@ b4_defines_if([
 /* 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.  */
 #if YYDEBUG
 
 /* Enable debugging if requested.  */
 #if YYDEBUG
 

+/* A pseudo ostream that takes yydebug_ into account.  */
+# define YYCDEBUG if (yydebug_) (*yycdebug_)
+

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


@@ -367,18 +507,22 @@ do {                                      \
 
 #else /* !YYDEBUG */
 
 
 #else /* !YYDEBUG */
 

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

 # define YY_SYMBOL_PRINT(Title, Type, Value, Location)
 # define YY_REDUCE_PRINT(Rule)
 # define YY_STACK_PRINT()
 
 #endif /* !YYDEBUG */
 
 # define YY_SYMBOL_PRINT(Title, Type, Value, Location)
 # define YY_REDUCE_PRINT(Rule)
 # define YY_STACK_PRINT()
 
 #endif /* !YYDEBUG */
 

+#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[
-{
+]b4_namespace_open[

 #if YYERROR_VERBOSE
 
   /* Return YYSTR after stripping away unnecessary quotes and
 #if YYERROR_VERBOSE
 
   /* Return YYSTR after stripping away unnecessary quotes and


@@ -421,9 +565,12 @@ namespace ]b4_namespace[
 #endif
 
   /// Build a parser object.
 #endif
 
   /// 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 YYDEBUG
+    ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
+      yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
+#endif]b4_parse_param_cons[

   {
   }
 
   {
   }
 


@@ -438,10 +585,10 @@ namespace ]b4_namespace[
 
   inline void
   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
 
   inline void
   ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,

-                          const semantic_type* yyvaluep, const location_type* yylocationp)
+                          const semantic_type& yyvalue, const location_type& yylocation)

   {
   {

-    YYUSE (yylocationp);
-    YYUSE (yyvaluep);
+    YYUSE (yylocation);
+    YYUSE (yyvalue);

     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


@@ -453,25 +600,25 @@ namespace ]b4_namespace[
 
   void
   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
 
   void
   ]b4_parser_class_name[::yy_symbol_print_ (int yytype,

-                          const semantic_type* yyvaluep, const location_type* yylocationp)
+                          const semantic_type& yyvalue, const location_type& yylocation)

   {
     *yycdebug_ << (yytype < yyntokens_ ? "token" : "nterm")
               << ' ' << yytname_[yytype] << " ("
   {
     *yycdebug_ << (yytype < yyntokens_ ? "token" : "nterm")
               << ' ' << yytname_[yytype] << " ("

-              << *yylocationp << ": ";
-    yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
+              << yylocation << ": ";
+    yy_symbol_value_print_ (yytype, yyvalue, yylocation);

     *yycdebug_ << ')';
   }
     *yycdebug_ << ')';
   }

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

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

-                          int yytype, semantic_type* yyvaluep, location_type* yylocationp)
+                          int yytype, semantic_type& yyvalue, location_type& yylocation)

   {
   {

-    YYUSE (yylocationp);

     YYUSE (yymsg);
     YYUSE (yymsg);

-    YYUSE (yyvaluep);
+    YYUSE (yyvalue);
+    YYUSE (yylocation);

 
 

-    YY_SYMBOL_PRINT (yymsg, yytype, yyvaluep, yylocationp);
+    YY_SYMBOL_PRINT (yymsg, yytype, yyvalue, yylocation);

 
     switch (yytype)
       {
 
     switch (yytype)
       {


@@ -481,6 +628,15 @@ namespace ]b4_namespace[
       }
   }
 
       }
   }
 

+  void
+  ]b4_parser_class_name[::yypush_ (state_type s,
+                           semantic_type& v, const location_type& l)
+  {
+    yystate_stack_.push (s);
+    yysemantic_stack_.push (v);
+    yylocation_stack_.push (l);
+  }
+

   void
   ]b4_parser_class_name[::yypop_ (unsigned int n)
   {
   void
   ]b4_parser_class_name[::yypop_ (unsigned int n)
   {


@@ -489,6 +645,7 @@ namespace ]b4_namespace[
     yylocation_stack_.pop (n);
   }
 
     yylocation_stack_.pop (n);
   }
 

+#if YYDEBUG

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


@@ -513,7 +670,7 @@ namespace ]b4_namespace[
   {
     yydebug_ = l;
   }
   {
     yydebug_ = l;
   }

-
+#endif

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


@@ -536,7 +693,7 @@ namespace ]b4_namespace[
     /// Location of the lookahead.
     location_type yylloc;
     /// The locations where the error started and ended.
     /// Location of the lookahead.
     location_type yylloc;
     /// The locations where the error started and ended.

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

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


@@ -562,13 +719,18 @@ m4_popdef([b4_at_dollar])])dnl
     yystate_stack_ = state_stack_type (0);
     yysemantic_stack_ = semantic_stack_type (0);
     yylocation_stack_ = location_stack_type (0);
     yystate_stack_ = state_stack_type (0);
     yysemantic_stack_ = semantic_stack_type (0);
     yylocation_stack_ = location_stack_type (0);

-    yysemantic_stack_.push (yylval);
-    yylocation_stack_.push (yylloc);
+    yypush_ (yystate, yylval, yylloc);

 
 

-    /* New state.  */
+    // A new state was pushed on the stack.
+    // Invariant: yystate == yystack_[0].state, i.e.,
+    // yystate was just pushed onto the state stack.

   yynewstate:
   yynewstate:

-    yystate_stack_.push (yystate);

     YYCDEBUG << "Entering state " << yystate << std::endl;
     YYCDEBUG << "Entering state " << yystate << std::endl;

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

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


@@ -599,7 +761,7 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
     else
       {
        yytoken = yytranslate_ (yychar);
     else
       {
        yytoken = yytranslate_ (yychar);

-       YY_SYMBOL_PRINT ("Next token is", yytoken, &yylval, &yylloc);
+       YY_SYMBOL_PRINT ("Next token is", yytoken, yylval, yylloc);

       }
 
     /* If the proper action on seeing token YYTOKEN is to reduce or to
       }
 
     /* If the proper action on seeing token YYTOKEN is to reduce or to


@@ -618,19 +780,11 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
        goto yyreduce;
       }
 
        goto yyreduce;
       }
 

-    /* Accept?  */
-    if (yyn == yyfinal_)
-      goto yyacceptlab;
-

     /* Shift the lookahead 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_;
-
-    yysemantic_stack_.push (yylval);
-    yylocation_stack_.push (yylloc);
+    /* Discard the token being shifted.  */
+    yychar = yyempty_;

 
     /* Count tokens shifted since error; after three, turn off error
        status.  */
 
     /* Count tokens shifted since error; after three, turn off error
        status.  */


@@ -638,6 +792,7 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
       --yyerrstatus_;
 
     yystate = yyn;
       --yyerrstatus_;
 
     yystate = yyn;

+    yypush_ (yystate, yylval, yylloc);

     goto yynewstate;
 
   /*-----------------------------------------------------------.
     goto yynewstate;
 
   /*-----------------------------------------------------------.


@@ -653,7 +808,11 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
   | yyreduce -- Do a reduction.  |
   `-----------------------------*/
   yyreduce:
   | yyreduce -- Do a reduction.  |
   `-----------------------------*/
   yyreduce:

-    yylen = yyr2_[yyn];
+    yylen = yyr2_[yyn];]b4_variant_if([
+    /* Variants are always initialized to an empty instance of the
+       correct type. The default $$=$1 rule is NOT applied when using
+       variants */
+    ]b4_symbol_variant([[yyr1_@{yyn@}]], [yyval], [build])[],[

     /* If YYLEN is nonzero, implement the default value of the action:
        `$$ = $1'.  Otherwise, use the top of the stack.
 
     /* If YYLEN is nonzero, implement the default value of the action:
        `$$ = $1'.  Otherwise, use the top of the stack.
 


@@ -661,9 +820,9 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
        This behavior is undocumented and Bison
        users should not rely upon it.  */
     if (yylen)
        This behavior is undocumented and Bison
        users should not rely upon it.  */
     if (yylen)

-      yyval = yysemantic_stack_[yylen - 1];
+      yyval = yysemantic_stack_@{yylen - 1@};

     else
     else

-      yyval = yysemantic_stack_[0];
+      yyval = yysemantic_stack_@{0@};])[

 
     {
       slice<location_type, location_stack_type> slice (yylocation_stack_, yylen);
 
     {
       slice<location_type, location_stack_type> slice (yylocation_stack_, yylen);


@@ -673,17 +832,15 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
     switch (yyn)
       {
        ]b4_user_actions[
     switch (yyn)
       {
        ]b4_user_actions[

-       default: break;
+       default:
+          break;

       }
       }

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

 
     yypop_ (yylen);
     yylen = 0;
     YY_STACK_PRINT ();
 
 
     yypop_ (yylen);
     yylen = 0;
     YY_STACK_PRINT ();
 

-    yysemantic_stack_.push (yyval);
-    yylocation_stack_.push (yyloc);
-

     /* Shift the result of the reduction.  */
     yyn = yyr1_[yyn];
     yystate = yypgoto_[yyn - yyntokens_] + yystate_stack_[0];
     /* Shift the result of the reduction.  */
     yyn = yyr1_[yyn];
     yystate = yypgoto_[yyn - yyntokens_] + yystate_stack_[0];


@@ -692,6 +849,7 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param))[;
       yystate = yytable_[yystate];
     else
       yystate = yydefgoto_[yyn - yyntokens_];
       yystate = yytable_[yystate];
     else
       yystate = yydefgoto_[yyn - yyntokens_];

+    yypush_ (yystate, yyval, yyloc);

     goto yynewstate;
 
   /*------------------------------------.
     goto yynewstate;
 
   /*------------------------------------.


@@ -720,7 +878,7 @@ b4_error_verbose_if([, yytoken])[));
          }
        else
          {
          }
        else
          {

-           yydestruct_ ("Error: discarding", yytoken, &yylval, &yylloc);
+           yydestruct_ ("Error: discarding", yytoken, yylval, yylloc);

            yychar = yyempty_;
          }
       }
            yychar = yyempty_;
          }
       }


@@ -770,33 +928,29 @@ b4_error_verbose_if([, yytoken])[));
        }
 
        /* Pop the current state because it cannot handle the error token.  */
        }
 
        /* Pop the current state because it cannot handle the error token.  */

-       if (yystate_stack_.height () == 1)
+       if (yystate_stack_.size () == 1)

        YYABORT;
 
        yyerror_range[0] = yylocation_stack_[0];
        yydestruct_ ("Error: popping",
                     yystos_[yystate],
        YYABORT;
 
        yyerror_range[0] = yylocation_stack_[0];
        yydestruct_ ("Error: popping",
                     yystos_[yystate],

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

        yypop_ ();
        yystate = yystate_stack_[0];
        YY_STACK_PRINT ();
       }
 
        yypop_ ();
        yystate = yystate_stack_[0];
        YY_STACK_PRINT ();
       }
 

-    if (yyn == yyfinal_)
-      goto yyacceptlab;
-

     yyerror_range[1] = yylloc;
     // Using YYLLOC is tempting, but would change the location of
     // the lookahead.  YYLOC is available though.
     YYLLOC_DEFAULT (yyloc, (yyerror_range - 1), 2);
     yyerror_range[1] = yylloc;
     // Using YYLLOC is tempting, but would change the location of
     // the lookahead.  YYLOC is available though.
     YYLLOC_DEFAULT (yyloc, (yyerror_range - 1), 2);

-    yysemantic_stack_.push (yylval);
-    yylocation_stack_.push (yyloc);

 
     /* Shift the error token.  */
     YY_SYMBOL_PRINT ("Shifting", yystos_[yyn],
 
     /* Shift the error token.  */
     YY_SYMBOL_PRINT ("Shifting", yystos_[yyn],

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

 
     yystate = yyn;
 
     yystate = yyn;

+    yypush_ (yystate, yylval, yyloc);

     goto yynewstate;
 
     /* Accept.  */
     goto yynewstate;
 
     /* Accept.  */


@@ -810,18 +964,18 @@ 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_)
+      yydestruct_ ("Cleanup: discarding lookahead", yytoken, yylval, yylloc);

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

-    while (yystate_stack_.height () != 1)
+    while (yystate_stack_.size () != 1)

       {
        yydestruct_ ("Cleanup: popping",
       {
        yydestruct_ ("Cleanup: popping",

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

        yypop_ ();
       }
 
        yypop_ ();
       }
 


@@ -1012,13 +1166,13 @@ 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 << " =",
                       yyrhs_[yyprhs_[yyrule] + yyi],
     /* The symbols being reduced.  */
     for (int yyi = 0; yyi < yynrhs; yyi++)
       YY_SYMBOL_PRINT ("   $" << yyi + 1 << " =",
                       yyrhs_[yyprhs_[yyrule] + yyi],

-                      &]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 // YYDEBUG
 


@@ -1050,21 +1204,20 @@ 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
 dnl
 
 ]b4_epilogue
 dnl

-@output b4_dir_prefix[]stack.hh
+@output(b4_dir_prefix[]stack.hh@)

 b4_copyright([Stack handling for Bison parsers in C++],
 b4_copyright([Stack handling for Bison parsers in C++],

-  [2002, 2003, 2004, 2005, 2006])[
+             [2002, 2003, 2004, 2005, 2006, 2007, 2008])[

 
 #ifndef BISON_STACK_HH
 # define BISON_STACK_HH
 
 #include <deque>
 
 
 #ifndef BISON_STACK_HH
 # define BISON_STACK_HH
 
 #include <deque>
 

-namespace ]b4_namespace[
-{
+]b4_namespace_open[

   template <class T, class S = std::deque<T> >
   class stack
   {
   template <class T, class S = std::deque<T> >
   class stack
   {


@@ -1112,17 +1265,17 @@ namespace ]b4_namespace[
     }
 
     inline
     }
 
     inline

-    unsigned int
-    height () const
+    typename S::size_type
+    size () const

     {
       return seq_.size ();
     }
 
     inline const_iterator begin () const { return seq_.rbegin (); }
     {
       return seq_.size ();
     }
 
     inline const_iterator begin () const { return seq_.rbegin (); }

-    inline const_iterator end () const { return seq_.rend (); }
+    inline const_iterator end ()   const { return seq_.rend ();   }

 
   private:
 
   private:

-
+    /// The wrapped container.

     S seq_;
   };
 
     S seq_;
   };
 


@@ -1150,7 +1303,8 @@ namespace ]b4_namespace[
     const S& stack_;
     unsigned int range_;
   };
     const S& stack_;
     unsigned int range_;
   };

-}
+]b4_namespace_close[

 
 

-#endif // not BISON_STACK_HH]
-m4_divert(-1)
+#endif // not BISON_STACK_HH[]dnl
+]
+m4_divert_pop(0)