news: restructure, document variants for C++

[bison.git] / data / lalr1.cc

diff --git a/data/lalr1.cc b/data/lalr1.cc
index 75eaf571e6c82afaa021c4245ac3b7fdcfa3d0e5..eb4883559a414287500ee6bfb3ac01f5b9c524e3 100644 (file)
--- a/data/lalr1.cc
+++ b/data/lalr1.cc
@@ -1,6 +1,6 @@
 # C++ skeleton for Bison
 
 # C++ skeleton for Bison
 

-# Copyright (C) 2002-2012 Free Software Foundation, Inc.
+# Copyright (C) 2002-2013 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
 
 # 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


@@ -20,7 +20,7 @@ m4_include(b4_pkgdatadir/[c++.m4])
 
 # b4_integral_parser_table_declare(TABLE-NAME, CONTENT, COMMENT)
 # --------------------------------------------------------------
 
 # b4_integral_parser_table_declare(TABLE-NAME, CONTENT, COMMENT)
 # --------------------------------------------------------------

-# Declare "parser::yy<TABLE-NAME>_" which contents is CONTENT.
+# Declare "parser::yy<TABLE-NAME>_" whose contents is CONTENT.

 m4_define([b4_integral_parser_table_declare],
 [m4_ifval([$3], [b4_comment([$3], [  ])
 ])dnl
 m4_define([b4_integral_parser_table_declare],
 [m4_ifval([$3], [b4_comment([$3], [  ])
 ])dnl


@@ -29,7 +29,7 @@ m4_define([b4_integral_parser_table_declare],
 
 # b4_integral_parser_table_define(TABLE-NAME, CONTENT, COMMENT)
 # -------------------------------------------------------------
 
 # b4_integral_parser_table_define(TABLE-NAME, CONTENT, COMMENT)
 # -------------------------------------------------------------

-# Define "parser::yy<TABLE-NAME>_" which contents is CONTENT.
+# Define "parser::yy<TABLE-NAME>_" whose contents is CONTENT.

 m4_define([b4_integral_parser_table_define],
 [  const b4_int_type_for([$2])
   b4_parser_class_name::yy$1_[[]] =
 m4_define([b4_integral_parser_table_define],
 [  const b4_int_type_for([$2])
   b4_parser_class_name::yy$1_[[]] =


@@ -114,16 +114,28 @@ b4_dollar_popdef[]dnl
 ])])
 
 
 ])])
 
 

+# b4_lex
+# ------
+# Call yylex.
+m4_define([b4_lex],
+[b4_token_ctor_if(
+[b4_function_call([yylex],
+                  [symbol_type], m4_ifdef([b4_lex_param], b4_lex_param))],
+[b4_function_call([yylex], [int],
+                  [b4_api_PREFIX[STYPE*], [&yyla.value]][]dnl
+b4_locations_if([, [[location*], [&yyla.location]]])dnl
+m4_ifdef([b4_lex_param], [, ]b4_lex_param))])])
+
+

 m4_pushdef([b4_copyright_years],
 m4_pushdef([b4_copyright_years],

-           [2002-2012])
+           [2002-2013])

 
 m4_define([b4_parser_class_name],
           [b4_percent_define_get([[parser_class_name]])])
 
 
 m4_define([b4_parser_class_name],
           [b4_percent_define_get([[parser_class_name]])])
 

-b4_locations_if([b4_percent_define_ifdef([[location_type]], [],
-  [# Backward compatibility.
+b4_bison_locations_if([# Backward compatibility.

    m4_define([b4_location_constructors])
    m4_define([b4_location_constructors])

-   m4_include(b4_pkgdatadir/[location.cc])])])
+   m4_include(b4_pkgdatadir/[location.cc])])

 m4_include(b4_pkgdatadir/[stack.hh])
 b4_variant_if([m4_include(b4_pkgdatadir/[variant.hh])])
 
 m4_include(b4_pkgdatadir/[stack.hh])
 b4_variant_if([m4_include(b4_pkgdatadir/[variant.hh])])
 


@@ -134,13 +146,13 @@ b4_variant_if([m4_include(b4_pkgdatadir/[variant.hh])])
 m4_define([b4_shared_declarations],
 [b4_percent_code_get([[requires]])[
 ]b4_parse_assert_if([# include <cassert>])[
 m4_define([b4_shared_declarations],
 [b4_percent_code_get([[requires]])[
 ]b4_parse_assert_if([# include <cassert>])[

-# include <deque>
+# include <vector>

 # include <iostream>
 # include <stdexcept>
 # include <string>]b4_defines_if([[
 # include "stack.hh"
 # include <iostream>
 # include <stdexcept>
 # include <string>]b4_defines_if([[
 # include "stack.hh"

-]b4_locations_if([b4_percent_define_ifdef([[location_type]], [],
-                                          [[# include "location.hh"]])])])[
+]b4_bison_locations_if([[# include "location.hh"]])])[
+]b4_variant_if([b4_variant_includes])[

 
 ]b4_YYDEBUG_define[
 
 
 ]b4_YYDEBUG_define[
 


@@ -148,9 +160,8 @@ m4_define([b4_shared_declarations],
 
 ]b4_defines_if([],
 [b4_stack_define
 
 ]b4_defines_if([],
 [b4_stack_define

-b4_locations_if([b4_percent_define_ifdef([[location_type]], [],
-                                         [b4_position_define
-b4_location_define])])])[
+b4_bison_locations_if([b4_position_define
+b4_location_define])])[

 
 ]b4_variant_if([b4_variant_define])[
 
 
 ]b4_variant_if([b4_variant_define])[
 


@@ -195,8 +206,9 @@ b4_location_define])])])[
 
     /// Generate an error message.
     /// \param yystate   the state where the error occurred.
 
     /// Generate an error message.
     /// \param yystate   the state where the error occurred.

-    /// \param yytoken   the lookahead token.
-    virtual std::string yysyntax_error_ (state_type yystate, int yytoken);
+    /// \param yytoken   the lookahead token type, or yyempty_.
+    virtual std::string yysyntax_error_ (state_type yystate,
+                                         symbol_number_type yytoken) const;

 
     /// Compute post-reduction state.
     /// \param yystate   the current state
 
     /// Compute post-reduction state.
     /// \param yystate   the current state


@@ -211,11 +223,12 @@ b4_location_define])])])[
     /// \param yyvalue   the value to check
     static bool yy_table_value_is_error_ (int yyvalue);
 
     /// \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;

     static const ]b4_int_type(b4_pact_ninf, b4_pact_ninf)[ yypact_ninf_;
     static const ]b4_int_type(b4_table_ninf, b4_table_ninf)[ yytable_ninf_;
 
     static const ]b4_int_type(b4_pact_ninf, b4_pact_ninf)[ yypact_ninf_;
     static const ]b4_int_type(b4_table_ninf, b4_table_ninf)[ yytable_ninf_;
 

+    /// Convert a scanner token number \a t to a symbol number.
+    static token_number_type yytranslate_ (]b4_token_ctor_if([token_type], [int])[ t);
+

     // Tables.
 ]b4_parser_tables_declare[]b4_error_verbose_if([
 
     // Tables.
 ]b4_parser_tables_declare[]b4_error_verbose_if([
 


@@ -227,7 +240,7 @@ b4_location_define])])])[
     static const char* const yytname_[];
 ]b4_token_table_if([[#if ]b4_api_PREFIX[DEBUG]])[
 ]b4_integral_parser_table_declare([rline], [b4_rline],
     static const char* const yytname_[];
 ]b4_token_table_if([[#if ]b4_api_PREFIX[DEBUG]])[
 ]b4_integral_parser_table_declare([rline], [b4_rline],

-     [YYRLINE[YYN] -- Source line where rule number YYN was defined.])[
+     [[YYRLINE[YYN] -- Source line where rule number YYN was defined.]])[

     /// Report on the debug stream that the rule \a r is going to be reduced.
     virtual void yy_reduce_print_ (int r);
     /// Print the state stack on the debug stream.
     /// Report on the debug stream that the rule \a r is going to be reduced.
     virtual void yy_reduce_print_ (int r);
     /// Print the state stack on the debug stream.


@@ -236,48 +249,61 @@ b4_location_define])])])[
     // Debugging.
     int yydebug_;
     std::ostream* yycdebug_;
     // Debugging.
     int yydebug_;
     std::ostream* yycdebug_;

-#endif // ]b4_api_PREFIX[DEBUG

 
 

-    /// Convert a scanner token number \a t to a symbol number.
-    static inline token_number_type yytranslate_ (]b4_lex_symbol_if([token_type], [int])[ t);
-
-#if ]b4_api_PREFIX[DEBUG

     /// \brief Display a symbol type, value and location.
     /// \param yyo    The output stream.
     /// \param yysym  The symbol.
     /// \brief Display a symbol type, value and location.
     /// \param yyo    The output stream.
     /// \param yysym  The symbol.

-    template <typename Exact>
-    void yy_print_ (std::ostream& yyo,
-                    const symbol_base_type<Exact>& yysym) const;
+    template <typename Base>
+    void yy_print_ (std::ostream& yyo, const basic_symbol<Base>& yysym) const;

 #endif
 
     /// \brief Reclaim the memory associated to a symbol.
     /// \param yymsg     Why this token is reclaimed.
     ///                  If null, print nothing.
     /// \param s         The symbol.
 #endif
 
     /// \brief Reclaim the memory associated to a symbol.
     /// \param yymsg     Why this token is reclaimed.
     ///                  If null, print nothing.
     /// \param s         The symbol.

-    template <typename Exact>
-    inline void yy_destroy_ (const char* yymsg,
-                             symbol_base_type<Exact>& yysym) const;
+    template <typename Base>
+    void yy_destroy_ (const char* yymsg, basic_symbol<Base>& yysym) const;

 
   private:
 
   private:

-    /// Element of the stack: a state and its attributes.
-    struct stack_symbol_type : symbol_base_type<stack_symbol_type>
+    /// Type access provider for state based symbols.
+    struct by_state

     {
     {

-      /// The parent class.
-      typedef symbol_base_type<stack_symbol_type> super_type;
-

       /// Default constructor.
       /// Default constructor.

-      inline stack_symbol_type ();
+      by_state ();
+
+      /// The symbol type as needed by the constructor.
+      typedef state_type kind_type;

 
       /// Constructor.
 
       /// Constructor.

-      inline stack_symbol_type (]b4_join([state_type s],
-                                         [const semantic_type& v],
-                                         b4_locations_if([const location_type& l]))[);
+      by_state (kind_type s);
+
+      /// Copy constructor.
+      by_state (const by_state& other);
+
+      /// Steal the symbol type from \a that.
+      void move (by_state& that);
+
+      /// The (internal) type number (corresponding to \a state).
+      /// "empty" when empty.
+      symbol_number_type type_get () const;
+
+      enum { empty = 0 };

 
       /// The state.
       state_type state;
 
       /// The state.
       state_type state;

+    };

 
 

-      /// The type (corresponding to \a state).
-      inline int type_get_ () const;
+    /// "Internal" symbol: element of the stack.
+    struct stack_symbol_type : basic_symbol<by_state>
+    {
+      /// Superclass.
+      typedef basic_symbol<by_state> super_type;
+      /// Construct an empty symbol.
+      stack_symbol_type ();
+      /// Steal the contents from \a sym to build this.
+      stack_symbol_type (state_type s, symbol_type& sym);
+      /// Assignment, needed by push_back.
+      stack_symbol_type& operator= (const stack_symbol_type& that);

     };
 
     /// Stack type.
     };
 
     /// Stack type.


@@ -291,7 +317,7 @@ b4_location_define])])])[
     ///             if null, no trace is output.
     /// \param s    the symbol
     /// \warning the contents of \a s.value is stolen.
     ///             if null, no trace is output.
     /// \param s    the symbol
     /// \warning the contents of \a s.value is stolen.

-    inline void yypush_ (const char* m, stack_symbol_type& s);
+    void yypush_ (const char* m, stack_symbol_type& s);

 
     /// Push a new look ahead token on the state on the stack.
     /// \param m    a debug message to display
 
     /// Push a new look ahead token on the state on the stack.
     /// \param m    a debug message to display


@@ -299,12 +325,12 @@ b4_location_define])])])[
     /// \param s    the state
     /// \param sym  the symbol (for its value and location).
     /// \warning the contents of \a s.value is stolen.
     /// \param s    the state
     /// \param sym  the symbol (for its value and location).
     /// \warning the contents of \a s.value is stolen.

-    inline void yypush_ (const char* m, state_type s, symbol_type& sym);
+    void yypush_ (const char* m, state_type s, symbol_type& sym);

 
     /// Pop \a n symbols the three stacks.
 
     /// Pop \a n symbols the three stacks.

-    inline void yypop_ (unsigned int n = 1);
+    void yypop_ (unsigned int n = 1);

 
 

-    /* Constants.  */
+    // Constants.

     enum
     {
       yyeof_ = 0,
     enum
     {
       yyeof_ = 0,


@@ -320,7 +346,7 @@ b4_location_define])])])[
 ]b4_parse_param_vars[
   };
 
 ]b4_parse_param_vars[
   };
 

-]b4_lex_symbol_if([b4_yytranslate_define
+]b4_token_ctor_if([b4_yytranslate_define

 b4_public_types_define])[
 ]b4_namespace_close[
 
 b4_public_types_define])[
 ]b4_namespace_close[
 


@@ -328,18 +354,15 @@ b4_public_types_define])[
 [b4_token_defines
 
 #ifndef ]b4_api_PREFIX[STYPE
 [b4_token_defines
 
 #ifndef ]b4_api_PREFIX[STYPE

- /* Redirection for backward compatibility.  */
+ // Redirection for backward compatibility.

 # define ]b4_api_PREFIX[STYPE b4_namespace_ref::b4_parser_class_name::semantic_type
 #endif
 ])[
 ]b4_percent_code_get([[provides]])[
 ]])
 
 # define ]b4_api_PREFIX[STYPE b4_namespace_ref::b4_parser_class_name::semantic_type
 #endif
 ])[
 ]b4_percent_code_get([[provides]])[
 ]])
 

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

 b4_defines_if(
 b4_defines_if(

-[m4_divert_push(0)dnl
-@output(b4_spec_defines_file@)@
+[b4_output_begin([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++])
 [
 /**


@@ -347,17 +370,16 @@ b4_copyright([Skeleton interface for Bison LALR(1) parsers in C++])
  ** Define the ]b4_namespace_ref[::parser class.
  */
 
  ** 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.

 
 ]b4_cpp_guard_open([b4_spec_defines_file])[
 ]b4_shared_declarations[
 ]b4_cpp_guard_close([b4_spec_defines_file])
 
 ]b4_cpp_guard_open([b4_spec_defines_file])[
 ]b4_shared_declarations[
 ]b4_cpp_guard_close([b4_spec_defines_file])

-m4_divert_pop(0)dnl
+b4_output_end()

 ])
 
 
 ])
 
 

-m4_divert_push(0)dnl
-@output(b4_parser_file_name@)@
+b4_output_begin([b4_parser_file_name])

 b4_copyright([Skeleton implementation for Bison LALR(1) parsers in C++])
 b4_percent_code_get([[top]])[]dnl
 m4_if(b4_prefix, [yy], [],
 b4_copyright([Skeleton implementation for Bison LALR(1) parsers in C++])
 b4_percent_code_get([[top]])[]dnl
 m4_if(b4_prefix, [yy], [],


@@ -373,14 +395,14 @@ m4_if(b4_prefix, [yy], [],
 ]b4_defines_if([[#include "@basename(]b4_spec_defines_file[@)"]],
                [b4_shared_declarations])[
 
 ]b4_defines_if([[#include "@basename(]b4_spec_defines_file[@)"]],
                [b4_shared_declarations])[
 

-/* User implementation prologue.  */
+// User implementation prologue.

 ]b4_user_post_prologue[
 ]b4_percent_code_get[
 
 #ifndef YY_
 # if defined YYENABLE_NLS && YYENABLE_NLS
 #  if ENABLE_NLS
 ]b4_user_post_prologue[
 ]b4_percent_code_get[
 
 #ifndef YY_
 # if defined YYENABLE_NLS && YYENABLE_NLS
 #  if ENABLE_NLS

-#   include <libintl.h> /* FIXME: INFRINGES ON USER NAME SPACE */
+#   include <libintl.h> // FIXME: INFRINGES ON USER NAME SPACE.

 #   define YY_(msgid) dgettext ("bison-runtime", msgid)
 #  endif
 # endif
 #   define YY_(msgid) dgettext ("bison-runtime", msgid)
 #  endif
 # endif


@@ -393,13 +415,13 @@ m4_if(b4_prefix, [yy], [],
 [#define YYRHSLOC(Rhs, K) ((Rhs)[K].location)
 ]b4_yylloc_default_define])[
 
 [#define YYRHSLOC(Rhs, K) ((Rhs)[K].location)
 ]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))

 
 

-/* Enable debugging if requested.  */
+// Enable debugging if requested.

 #if ]b4_api_PREFIX[DEBUG
 
 #if ]b4_api_PREFIX[DEBUG
 

-/* A pseudo ostream that takes yydebug_ into account.  */
+// A pseudo ostream that takes yydebug_ into account.

 # define YYCDEBUG if (yydebug_) (*yycdebug_)
 
 # define YY_SYMBOL_PRINT(Title, Symbol)         \
 # define YYCDEBUG if (yydebug_) (*yycdebug_)
 
 # define YY_SYMBOL_PRINT(Title, Symbol)         \


@@ -424,14 +446,14 @@ m4_if(b4_prefix, [yy], [],
       yystack_print_ ();                \
   } while (false)
 
       yystack_print_ ();                \
   } while (false)
 

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

 
 # define YYCDEBUG if (false) std::cerr
 # define YY_SYMBOL_PRINT(Title, Symbol)  YYUSE(Symbol)
 # define YY_REDUCE_PRINT(Rule)           static_cast<void>(0)
 # define YY_STACK_PRINT()                static_cast<void>(0)
 
 
 # define YYCDEBUG if (false) std::cerr
 # define YY_SYMBOL_PRINT(Title, Symbol)  YYUSE(Symbol)
 # define YY_REDUCE_PRINT(Rule)           static_cast<void>(0)
 # define YY_STACK_PRINT()                static_cast<void>(0)
 

-#endif /* !]b4_api_PREFIX[DEBUG */
+#endif // !]b4_api_PREFIX[DEBUG

 
 #define yyerrok         (yyerrstatus_ = 0)
 #define yyclearin       (yyempty = true)
 
 #define yyerrok         (yyerrstatus_ = 0)
 #define yyclearin       (yyempty = true)


@@ -466,7 +488,7 @@ m4_if(b4_prefix, [yy], [],
             case '\\':
               if (*++yyp != '\\')
                 goto do_not_strip_quotes;
             case '\\':
               if (*++yyp != '\\')
                 goto do_not_strip_quotes;

-              /* Fall through.  */
+              // Fall through.

             default:
               yyr += *yyp;
               break;
             default:
               yyr += *yyp;
               break;


@@ -488,73 +510,105 @@ m4_if(b4_prefix, [yy], [],
     ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
       yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 #endif]b4_parse_param_cons[
     ]m4_ifset([b4_parse_param], [  ], [ :])[yydebug_ (false),
       yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
 #endif]b4_parse_param_cons[

-  {
-  }
+  {}

 
   ]b4_parser_class_name::~b4_parser_class_name[ ()
 
   ]b4_parser_class_name::~b4_parser_class_name[ ()

-  {
-  }
+  {}

 
 
   /*---------------.
   | Symbol types.  |
   `---------------*/
 
 
 
   /*---------------.
   | Symbol types.  |
   `---------------*/
 

-]b4_lex_symbol_if([], [b4_public_types_define])[
+]b4_token_ctor_if([], [b4_public_types_define])[

 
 

-  // stack_symbol_type.
-  ]b4_parser_class_name[::stack_symbol_type::stack_symbol_type ()
-    : super_type ()
-    , state ()
+  // by_state.
+  inline
+  ]b4_parser_class_name[::by_state::by_state ()
+    : state (empty)
+  {}
+
+  inline
+  ]b4_parser_class_name[::by_state::by_state (const by_state& other)
+    : state (other.state)
+  {}
+
+  inline
+  void
+  ]b4_parser_class_name[::by_state::move (by_state& that)

   {
   {

+    state = that.state;
+    that.state = empty;

   }
 
   }
 

-  ]b4_parser_class_name[::stack_symbol_type::stack_symbol_type (]b4_join(
-                 [state_type s],
-                 [const semantic_type& v],
-                 b4_locations_if([const location_type& l]))[)
-    : super_type (v]b4_locations_if([, l])[)
-    , state (s)
+  inline
+  ]b4_parser_class_name[::by_state::by_state (state_type s)
+    : state (s)
+  {}
+
+  inline
+  ]b4_parser_class_name[::symbol_number_type
+  ]b4_parser_class_name[::by_state::type_get () const

   {
   {

+    return state == empty ? 0 : yystos_[state];

   }
 
   }
 

-  int
-  ]b4_parser_class_name[::stack_symbol_type::type_get_ () const
+  inline
+  ]b4_parser_class_name[::stack_symbol_type::stack_symbol_type ()
+  {}
+
+
+  inline
+  ]b4_parser_class_name[::stack_symbol_type::stack_symbol_type (state_type s, symbol_type& that)
+    : super_type (s]b4_locations_if([, that.location])[)

   {
   {

-    return yystos_[state];
+    ]b4_variant_if([b4_symbol_variant([that.type_get ()],
+                                      [value], [move], [that.value])],
+                   [[value = that.value;]])[
+    // that is emptied.
+    that.type = empty;
+  }
+
+  inline
+  ]b4_parser_class_name[::stack_symbol_type&
+  ]b4_parser_class_name[::stack_symbol_type::operator= (const stack_symbol_type& that)
+  {
+    state = that.state;
+    ]b4_variant_if([b4_symbol_variant([that.type_get ()],
+                                      [value], [copy], [that.value])],
+                   [[value = that.value;]])[]b4_locations_if([
+    location = that.location;])[
+    return *this;

   }
 
 
   }
 
 

-  template <typename Exact>
+  template <typename Base>
+  inline

   void
   void

-  ]b4_parser_class_name[::yy_destroy_ (const char* yymsg,
-                                       symbol_base_type<Exact>& yysym) const
+  ]b4_parser_class_name[::yy_destroy_ (const char* yymsg, basic_symbol<Base>& yysym) const

   {
     if (yymsg)
   {
     if (yymsg)

-      YY_SYMBOL_PRINT (yymsg, yysym);
+      YY_SYMBOL_PRINT (yymsg, yysym);]b4_variant_if([], [

 
     // User destructor.
 
     // User destructor.

-    int yytype = yysym.type_get ();
+    symbol_number_type yytype = yysym.type_get ();

     switch (yytype)
       {
 ]b4_symbol_foreach([b4_symbol_destructor])dnl
 [       default:
           break;
     switch (yytype)
       {
 ]b4_symbol_foreach([b4_symbol_destructor])dnl
 [       default:
           break;

-      }]b4_variant_if([
-
-    // Type destructor.
-  b4_symbol_variant([[yytype]], [[yysym.value]], [[template destroy]])])[
+      }])[

   }
 
 #if ]b4_api_PREFIX[DEBUG
   }
 
 #if ]b4_api_PREFIX[DEBUG

-  template <typename Exact>
+  template <typename Base>

   void
   ]b4_parser_class_name[::yy_print_ (std::ostream& yyo,
   void
   ]b4_parser_class_name[::yy_print_ (std::ostream& yyo,

-                                     const symbol_base_type<Exact>& yysym) const
+                                     const basic_symbol<Base>& yysym) const

   {
     std::ostream& yyoutput = yyo;
     YYUSE (yyoutput);
   {
     std::ostream& yyoutput = yyo;
     YYUSE (yyoutput);

-    int yytype = yysym.type_get ();
+    symbol_number_type yytype = yysym.type_get ();

     yyo << (yytype < yyntokens_ ? "token" : "nterm")
         << ' ' << yytname_[yytype] << " ("]b4_locations_if([
         << yysym.location << ": "])[;
     yyo << (yytype < yyntokens_ ? "token" : "nterm")
         << ' ' << yytname_[yytype] << " ("]b4_locations_if([
         << yysym.location << ": "])[;


@@ -568,40 +622,24 @@ m4_if(b4_prefix, [yy], [],
   }
 #endif
 
   }
 #endif
 

+  inline

   void
   void

-  ]b4_parser_class_name[::yypush_ (const char* m, state_type s,
-                                   symbol_type& sym)
+  ]b4_parser_class_name[::yypush_ (const char* m, state_type s, symbol_type& sym)

   {
   {

-    if (m)
-      YY_SYMBOL_PRINT (m, sym);
-]b4_variant_if(
-[[    yystack_.push (stack_symbol_type (]b4_join(
-                    [s],
-                    [semantic_type()],
-                    b4_locations_if([sym.location]))[));
-    ]b4_symbol_variant([[yystos_[s]]], [[yystack_[0].value]],
-                       [build], [sym.value])],
-[[    yystack_.push (stack_symbol_type (]b4_join(
-                      [s],
-                      [sym.value],
-                      b4_locations_if([sym.location]))[));]])[
+    stack_symbol_type t (s, sym);
+    yypush_ (m, t);

   }
 
   }
 

+  inline

   void
   ]b4_parser_class_name[::yypush_ (const char* m, stack_symbol_type& s)
   {
     if (m)
       YY_SYMBOL_PRINT (m, s);
   void
   ]b4_parser_class_name[::yypush_ (const char* m, stack_symbol_type& s)
   {
     if (m)
       YY_SYMBOL_PRINT (m, s);

-]b4_variant_if(
-[[    yystack_.push (stack_symbol_type (]b4_join(
-                       [s.state],
-                       [semantic_type()],
-                       b4_locations_if([s.location]))[));
-    ]b4_symbol_variant([[yystos_[s.state]]], [[yystack_[0].value]],
-                       [build], [s.value])],
-[    yystack_.push (s);])[
+    yystack_.push (s);

   }
 
   }
 

+  inline

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


@@ -663,11 +701,11 @@ m4_if(b4_prefix, [yy], [],
     /// Whether yyla contains a lookahead.
     bool yyempty = true;
 
     /// Whether yyla contains a lookahead.
     bool yyempty = true;
 

-    /* State.  */
+    // State.

     int yyn;
     int yylen = 0;
 
     int yyn;
     int yylen = 0;
 

-    /* Error handling.  */
+    // Error handling.

     int yynerrs_ = 0;
     int yyerrstatus_ = 0;
 
     int yynerrs_ = 0;
     int yyerrstatus_ = 0;
 


@@ -683,11 +721,15 @@ m4_if(b4_prefix, [yy], [],
     /// The return value of parse ().
     int yyresult;
 
     /// The return value of parse ().
     int yyresult;
 

+    // FIXME: This shoud be completely indented.  It is not yet to
+    // avoid gratuitous conflicts when merging into the master branch.
+    try
+      {

     YYCDEBUG << "Starting parse" << std::endl;
 
 ]m4_ifdef([b4_initial_action], [
 b4_dollar_pushdef([yyla.value], [], [yyla.location])dnl
     YYCDEBUG << "Starting parse" << std::endl;
 
 ]m4_ifdef([b4_initial_action], [
 b4_dollar_pushdef([yyla.value], [], [yyla.location])dnl

-    /* User initialization code.  */
+    // User initialization code.

     b4_user_initial_action
 b4_dollar_popdef])[]dnl
 
     b4_user_initial_action
 b4_dollar_popdef])[]dnl
 


@@ -702,33 +744,29 @@ b4_dollar_popdef])[]dnl
   yynewstate:
     YYCDEBUG << "Entering state " << yystack_[0].state << std::endl;
 
   yynewstate:
     YYCDEBUG << "Entering state " << yystack_[0].state << std::endl;
 

-    /* Accept?  */
+    // Accept?

     if (yystack_[0].state == yyfinal_)
       goto yyacceptlab;
 
     goto yybackup;
 
     if (yystack_[0].state == yyfinal_)
       goto yyacceptlab;
 
     goto yybackup;
 

-    /* Backup.  */
+    // Backup.

   yybackup:
 
   yybackup:
 

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

     yyn = yypact_[yystack_[0].state];
     if (yy_pact_value_is_default_ (yyn))
       goto yydefault;
 
     yyn = yypact_[yystack_[0].state];
     if (yy_pact_value_is_default_ (yyn))
       goto yydefault;
 

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

     if (yyempty)
       {
         YYCDEBUG << "Reading a token: ";
         try
     if (yyempty)
       {
         YYCDEBUG << "Reading a token: ";
         try

-          {
-]b4_lex_symbol_if(
-[            yyla = b4_function_call([yylex], [symbol_type],
-                                     m4_ifdef([b4_lex_param], b4_lex_param));],
-[            yyla.type = yytranslate_ (b4_function_call([yylex], [int],
-                                     [b4_api_PREFIX[STYPE*], [&yyla.value]][]dnl
-b4_locations_if([, [[location*], [&yyla.location]]])dnl
-m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
+          {]b4_token_ctor_if([[
+            symbol_type yylookahead (]b4_lex[);
+            yyla.move (yylookahead);]], [[
+            yyla.type = yytranslate_ (]b4_lex[);]])[

           }
         catch (const syntax_error& yyexc)
           {
           }
         catch (const syntax_error& yyexc)
           {


@@ -741,11 +779,11 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
 
     /* If the proper action on seeing token YYLA.TYPE is to reduce or
        to detect an error, take that action.  */
 
     /* If the proper action on seeing token YYLA.TYPE is to reduce or
        to detect an error, take that action.  */

-    yyn += yyla.type;
-    if (yyn < 0 || yylast_ < yyn || yycheck_[yyn] != yyla.type)
+    yyn += yyla.type_get ();
+    if (yyn < 0 || yylast_ < yyn || yycheck_[yyn] != yyla.type_get ())

       goto yydefault;
 
       goto yydefault;
 

-    /* Reduce or error.  */
+    // Reduce or error.

     yyn = yytable_[yyn];
     if (yyn <= 0)
       {
     yyn = yytable_[yyn];
     if (yyn <= 0)
       {


@@ -755,15 +793,14 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
         goto yyreduce;
       }
 
         goto yyreduce;
       }
 

-    /* Discard the token being shifted.  */
+    // Discard the token being shifted.

     yyempty = true;
 
     yyempty = true;
 

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

     if (yyerrstatus_)
       --yyerrstatus_;
 
     if (yyerrstatus_)
       --yyerrstatus_;
 

-    /* Shift the lookahead token.  */
+    // Shift the lookahead token.

     yypush_ ("Shifting", yyn, yyla);
     goto yynewstate;
 
     yypush_ ("Shifting", yyn, yyla);
     goto yynewstate;
 


@@ -821,26 +858,11 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
         YYERROR;
       }
     YY_SYMBOL_PRINT ("-> $$ =", yylhs);
         YYERROR;
       }
     YY_SYMBOL_PRINT ("-> $$ =", yylhs);

-]b4_variant_if([[
-    // Destroy the rhs symbols.
-    for (int i = 0; i < yylen; ++i)
-      // Destroy a variant which value may have been swapped with
-      // yylhs.value (for instance if the action was "std::swap($$,
-      // $1)").  The value of yylhs.value (hence possibly one of these
-      // rhs symbols) depends on the default construction for this
-      // type.  In the case of pointers for instance, no
-      // initialization is done, so the value is junk.  Therefore do
-      // not try to report the value of symbols about to be destroyed
-      // in the debug trace, it's possibly junk.  Hence yymsg = 0.
-      // Besides, that keeps exactly the same traces as with the other
-      // Bison skeletons.
-      yy_destroy_ (YY_NULL, yystack_[i]);]])[
-

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

-    /* Shift the result of the reduction.  */
+    // Shift the result of the reduction.

     yypush_ (YY_NULL, yylhs);
     goto yynewstate;
 
     yypush_ (YY_NULL, yylhs);
     goto yynewstate;
 


@@ -848,13 +870,13 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
   | yyerrlab -- here on detecting error.  |
   `--------------------------------------*/
   yyerrlab:
   | yyerrlab -- here on detecting error.  |
   `--------------------------------------*/
   yyerrlab:

-    /* If not already recovering from an error, report this error.  */
+    // If not already recovering from an error, report this error.

     if (!yyerrstatus_)
       {
         ++yynerrs_;
         error (]b4_join(b4_locations_if([yyla.location]),
                         [[yysyntax_error_ (yystack_[0].state,
     if (!yyerrstatus_)
       {
         ++yynerrs_;
         error (]b4_join(b4_locations_if([yyla.location]),
                         [[yysyntax_error_ (yystack_[0].state,

-                                           yyempty ? yyempty_ : yyla.type)]])[);
+                                           yyempty ? yyempty_ : yyla.type_get ())]])[);

       }
 
 ]b4_locations_if([[
       }
 
 ]b4_locations_if([[


@@ -864,8 +886,8 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
         /* If just tried and failed to reuse lookahead token after an
            error, discard it.  */
 
         /* If just tried and failed to reuse lookahead token after an
            error, discard it.  */
 

-        /* Return failure if at end of input.  */
-        if (yyla.type == yyeof_)
+        // Return failure if at end of input.
+        if (yyla.type_get () == yyeof_)

           YYABORT;
         else if (!yyempty)
           {
           YYABORT;
         else if (!yyempty)
           {


@@ -874,8 +896,7 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
           }
       }
 
           }
       }
 

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

     goto yyerrlab1;
 
 
     goto yyerrlab1;
 
 


@@ -891,8 +912,9 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
       goto yyerrorlab;]b4_locations_if([[
     yyerror_range[1].location = yystack_[yylen - 1].location;]])b4_variant_if([[
     /* $$ was initialized before running the user action.  */
       goto yyerrorlab;]b4_locations_if([[
     yyerror_range[1].location = yystack_[yylen - 1].location;]])b4_variant_if([[
     /* $$ was initialized before running the user action.  */

-    yy_destroy_ ("Error: discarding", yylhs);]])[
-    /* Do not reclaim the symbols of the rule which action triggered
+    YY_SYMBOL_PRINT ("Error: discarding", yylhs);
+    yylhs.~stack_symbol_type();]])[
+    /* Do not reclaim the symbols of the rule whose action triggered

        this YYERROR.  */
     yypop_ (yylen);
     yylen = 0;
        this YYERROR.  */
     yypop_ (yylen);
     yylen = 0;


@@ -902,7 +924,7 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
   | yyerrlab1 -- common code for both syntax error and YYERROR.  |
   `-------------------------------------------------------------*/
   yyerrlab1:
   | yyerrlab1 -- common code for both syntax error and YYERROR.  |
   `-------------------------------------------------------------*/
   yyerrlab1:

-    yyerrstatus_ = 3;   /* Each real token shifted decrements this.  */
+    yyerrstatus_ = 3;   // Each real token shifted decrements this.

     {
       stack_symbol_type error_token;
       for (;;)
     {
       stack_symbol_type error_token;
       for (;;)


@@ -932,18 +954,18 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
       yyerror_range[2].location = yyla.location;
       YYLLOC_DEFAULT (error_token.location, yyerror_range, 2);]])[
 
       yyerror_range[2].location = yyla.location;
       YYLLOC_DEFAULT (error_token.location, yyerror_range, 2);]])[
 

-      /* Shift the error token.  */
+      // Shift the error token.

       error_token.state = yyn;
       yypush_ ("Shifting", error_token);
     }
     goto yynewstate;
 
       error_token.state = yyn;
       yypush_ ("Shifting", error_token);
     }
     goto yynewstate;
 

-    /* Accept.  */
+    // Accept.

   yyacceptlab:
     yyresult = 0;
     goto yyreturn;
 
   yyacceptlab:
     yyresult = 0;
     goto yyreturn;
 

-    /* Abort.  */
+    // Abort.

   yyabortlab:
     yyresult = 1;
     goto yyreturn;
   yyabortlab:
     yyresult = 1;
     goto yyreturn;


@@ -952,10 +974,10 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
     if (!yyempty)
       yy_destroy_ ("Cleanup: discarding lookahead", yyla);
 
     if (!yyempty)
       yy_destroy_ ("Cleanup: discarding lookahead", yyla);
 

-    /* Do not reclaim the symbols of the rule which action triggered
+    /* Do not reclaim the symbols of the rule whose action triggered

        this YYABORT or YYACCEPT.  */
     yypop_ (yylen);
        this YYABORT or YYACCEPT.  */
     yypop_ (yylen);

-    while (yystack_.size () != 1)
+    while (1 < yystack_.size ())

       {
         yy_destroy_ ("Cleanup: popping", yystack_[0]);
         yypop_ ();
       {
         yy_destroy_ ("Cleanup: popping", yystack_[0]);
         yypop_ ();


@@ -963,6 +985,23 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
 
     return yyresult;
   }
 
     return yyresult;
   }

+    catch (...)
+      {
+        YYCDEBUG << "Exception caught: cleaning lookahead and stack"
+                 << std::endl;
+        // Do not try to display the values of the reclaimed symbols,
+        // as their printer might throw an exception.
+        if (!yyempty)
+          yy_destroy_ (YY_NULL, yyla);
+
+        while (1 < yystack_.size ())
+          {
+            yy_destroy_ (YY_NULL, yystack_[0]);
+            yypop_ ();
+          }
+        throw;
+      }
+  }

 
   void
   ]b4_parser_class_name[::error (const syntax_error& yyexc)
 
   void
   ]b4_parser_class_name[::error (const syntax_error& yyexc)


@@ -974,8 +1013,8 @@ m4_ifdef([b4_lex_param], [, ]b4_lex_param)));])[
   // Generate an error message.
   std::string
   ]b4_parser_class_name[::yysyntax_error_ (]dnl
   // Generate an error message.
   std::string
   ]b4_parser_class_name[::yysyntax_error_ (]dnl

-b4_error_verbose_if([state_type yystate, int yytoken],
-                    [int, int])[)
+b4_error_verbose_if([state_type yystate, symbol_number_type yytoken],
+                    [state_type, symbol_number_type])[) const

   {]b4_error_verbose_if([[
     std::string yyres;
     // Number of reported tokens (one for the "unexpected", one per
   {]b4_error_verbose_if([[
     std::string yyres;
     // Number of reported tokens (one for the "unexpected", one per


@@ -1021,7 +1060,7 @@ b4_error_verbose_if([state_type yystate, int yytoken],
                YYCHECK.  In other words, skip the first -YYN actions for
                this state because they are default actions.  */
             int yyxbegin = yyn < 0 ? -yyn : 0;
                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.  */
+            // 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)
             int yychecklim = yylast_ - yyn + 1;
             int yyxend = yychecklim < yyntokens_ ? yychecklim : yyntokens_;
             for (int yyx = yyxbegin; yyx < yyxend; ++yyx)


@@ -1077,8 +1116,8 @@ b4_error_verbose_if([state_type yystate, int yytoken],
 ]b4_parser_tables_define[
 
 ]b4_token_table_if([], [[#if ]b4_api_PREFIX[DEBUG]])[
 ]b4_parser_tables_define[
 
 ]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.  */
+  // YYTNAME[SYMBOL-NUM] -- String name of the symbol SYMBOL-NUM.
+  // First, the terminals, then, starting at \a yyntokens_, nonterminals.

   const char*
   const ]b4_parser_class_name[::yytname_[] =
   {
   const char*
   const ]b4_parser_class_name[::yytname_[] =
   {


@@ -1107,18 +1146,20 @@ b4_error_verbose_if([state_type yystate, int yytoken],
   {
     unsigned int yylno = yyrline_[yyrule];
     int yynrhs = yyr2_[yyrule];
   {
     unsigned int yylno = yyrline_[yyrule];
     int yynrhs = yyr2_[yyrule];

-    /* Print the symbols being reduced, and their result.  */
+    // Print the symbols being reduced, and their result.

     *yycdebug_ << "Reducing stack by rule " << yyrule - 1
                << " (line " << yylno << "):" << std::endl;
     *yycdebug_ << "Reducing stack by rule " << yyrule - 1
                << " (line " << yylno << "):" << std::endl;

-    /* The symbols being reduced.  */
+    // The symbols being reduced.

     for (int yyi = 0; yyi < yynrhs; yyi++)
       YY_SYMBOL_PRINT ("   $" << yyi + 1 << " =",
                        ]b4_rhs_data(yynrhs, yyi + 1)[);
   }
 #endif // ]b4_api_PREFIX[DEBUG
 
     for (int yyi = 0; yyi < yynrhs; yyi++)
       YY_SYMBOL_PRINT ("   $" << yyi + 1 << " =",
                        ]b4_rhs_data(yynrhs, yyi + 1)[);
   }
 #endif // ]b4_api_PREFIX[DEBUG
 

-]b4_lex_symbol_if([], [b4_yytranslate_define])[
+]b4_token_ctor_if([], [b4_yytranslate_define])[

 ]b4_namespace_close[
 ]b4_epilogue[]dnl
 ]b4_namespace_close[
 ]b4_epilogue[]dnl

-m4_divert_pop(0)
+b4_output_end()
+
+

 m4_popdef([b4_copyright_years])dnl
 m4_popdef([b4_copyright_years])dnl