diff -r 2fe1408b6811 -r e1b950c65cb4 epoc32/include/stdapis/boost/variant.hpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/epoc32/include/stdapis/boost/variant.hpp	Wed Mar 31 12:27:01 2010 +0100
@@ -0,0 +1,1833 @@
+//-----------------------------------------------------------------------------
+// boost variant/variant.hpp header file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2002-2003
+// Eric Friedman, Itay Maman
+//
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+/*
+ * © Portions copyright (c) 2006-2007 Nokia Corporation.  All rights reserved.
+*/
+#ifndef BOOST_VARIANT_VARIANT_HPP
+#define BOOST_VARIANT_VARIANT_HPP
+
+#include <cstddef> // for std::size_t
+#include <new> // for placement new
+#ifdef __SYMBIAN32__
+#include <string>
+#endif
+#include <typeinfo> // for typeid, std::type_info
+
+#include "boost/variant/detail/config.hpp"
+#include "boost/mpl/aux_/config/eti.hpp"
+#include "boost/mpl/aux_/value_wknd.hpp"
+
+#include "boost/variant/variant_fwd.hpp"
+#include "boost/variant/detail/backup_holder.hpp"
+#include "boost/variant/detail/enable_recursive_fwd.hpp"
+#include "boost/variant/detail/forced_return.hpp"
+#include "boost/variant/detail/initializer.hpp"
+#include "boost/variant/detail/make_variant_list.hpp"
+#include "boost/variant/detail/over_sequence.hpp"
+#include "boost/variant/detail/visitation_impl.hpp"
+
+#include "boost/variant/detail/generic_result_type.hpp"
+#include "boost/variant/detail/has_nothrow_move.hpp"
+#include "boost/variant/detail/move.hpp"
+
+#include "boost/detail/reference_content.hpp"
+#include "boost/aligned_storage.hpp"
+#include "boost/blank.hpp"
+#include "boost/static_assert.hpp"
+#include "boost/preprocessor/cat.hpp"
+#include "boost/preprocessor/repeat.hpp"
+#include "boost/type_traits/alignment_of.hpp"
+#include "boost/type_traits/add_const.hpp"
+#include "boost/type_traits/has_nothrow_constructor.hpp"
+#include "boost/type_traits/has_nothrow_copy.hpp"
+#include "boost/type_traits/is_const.hpp"
+#include "boost/type_traits/is_same.hpp"
+#include "boost/utility/enable_if.hpp"
+#include "boost/variant/recursive_wrapper_fwd.hpp"
+#include "boost/variant/static_visitor.hpp"
+
+#include "boost/mpl/eval_if.hpp"
+#include "boost/mpl/begin_end.hpp"
+#include "boost/mpl/bool.hpp"
+#include "boost/mpl/empty.hpp"
+#include "boost/mpl/find_if.hpp"
+#include "boost/mpl/front.hpp"
+#include "boost/mpl/identity.hpp"
+#include "boost/mpl/if.hpp"
+#include "boost/mpl/int.hpp"
+#include "boost/mpl/is_sequence.hpp"
+#include "boost/mpl/iterator_range.hpp"
+#include "boost/mpl/iter_fold_if.hpp"
+#include "boost/mpl/logical.hpp"
+#include "boost/mpl/max_element.hpp"
+#include "boost/mpl/next.hpp"
+#include "boost/mpl/deref.hpp"
+#include "boost/mpl/pair.hpp"
+#include "boost/mpl/protect.hpp"
+#include "boost/mpl/push_front.hpp"
+#include "boost/mpl/same_as.hpp"
+#include "boost/mpl/size_t.hpp"
+#include "boost/mpl/sizeof.hpp"
+#include "boost/mpl/transform.hpp"
+#include "boost/mpl/assert.hpp"
+
+///////////////////////////////////////////////////////////////////////////////
+// Implementation Macros:
+//
+// BOOST_VARIANT_VISITATION_UNROLLING_LIMIT
+//   Defined in boost/variant/detail/visitation_impl.hpp.
+//
+// BOOST_VARIANT_MINIMIZE_SIZE
+//   When #defined, implementation employs all known means to minimize the
+//   size of variant obje   cts. However, often unsuccessful due to alignment
+//   issues, and potentially harmful to runtime speed, so not enabled by
+//   default. (TODO: Investigate further.)
+
+#if defined(BOOST_VARIANT_MINIMIZE_SIZE)
+#   include <climits> // for SCHAR_MAX
+#   include "boost/mpl/eval_if.hpp"
+#   include "boost/mpl/equal_to.hpp"
+#   include "boost/mpl/identity.hpp"
+#   include "boost/mpl/int.hpp"
+#   include "boost/mpl/if.hpp"
+#   include "boost/mpl/less.hpp"
+#   include "boost/mpl/long.hpp"
+#   include "boost/mpl/O1_size.hpp"
+#endif
+
+
+namespace boost {
+
+namespace detail { namespace variant {
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) metafunction max_value
+//
+// Finds the maximum value of the unary metafunction F over Sequence.
+//
+template <typename Sequence, typename F>
+struct max_value
+{
+private: // helpers, for metafunction result (below)
+
+    typedef typename mpl::transform1<Sequence, F>::type transformed_;
+    typedef typename mpl::max_element<transformed_
+          
+        >::type max_it;
+
+public: // metafunction result
+
+    typedef typename mpl::deref<max_it>::type
+        type;
+
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) metafunction find_fallback_type
+//
+// Provides a fallback (i.e., nothrow default-constructible) type from the
+// specified sequence, or no_fallback_type if not found.
+//
+// This implementation is designed to prefer boost::blank over other potential
+// fallback types, regardless of its position in the specified sequence.
+//
+
+class no_fallback_type;
+
+struct find_fallback_type_pred
+{
+    template <typename Iterator>
+    struct apply
+    {
+    private:
+        typedef typename mpl::deref<Iterator>::type t_;
+
+    public:
+        typedef mpl::not_< has_nothrow_constructor<t_> > type;
+    };
+};
+
+template <typename Types>
+struct find_fallback_type
+{
+private: // helpers, for metafunction result (below)
+
+    typedef typename mpl::end<Types>::type end_it;
+
+    // [Find the first suitable fallback type...]
+
+    typedef typename mpl::iter_fold_if<
+          Types
+        , mpl::int_<0>, mpl::protect< mpl::next<> >
+        , mpl::protect< find_fallback_type_pred >
+        >::type first_result_;
+
+    typedef typename first_result_::first first_result_index;
+    typedef typename first_result_::second first_result_it;
+
+    // [...now search the rest of the sequence for boost::blank...]
+
+    typedef typename mpl::iter_fold_if<
+          mpl::iterator_range< first_result_it,end_it >
+        , first_result_index, mpl::protect< mpl::next<> >
+        , mpl::protect< mpl::not_same_as<boost::blank> >
+        >::type second_result_;
+
+    typedef typename second_result_::second second_result_it;
+
+public: // metafunction result
+
+    // [...and return the results of the search:]
+    typedef typename mpl::eval_if<
+          is_same< second_result_it,end_it >
+        , mpl::if_<
+              is_same< first_result_it,end_it >
+            , mpl::pair< no_fallback_type,no_fallback_type >
+            , first_result_
+            >
+        , mpl::identity< second_result_ >
+        >::type type;
+
+};
+
+#if defined(BOOST_MPL_CFG_MSVC_60_ETI_BUG)
+
+template<>
+struct find_fallback_type<int>
+{
+    typedef mpl::pair< no_fallback_type,no_fallback_type > type;
+};
+
+#endif // BOOST_MPL_CFG_MSVC_60_ETI_BUG workaround
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) metafunction make_storage
+//
+// Provides an aligned storage type capable of holding any of the types
+// specified in the given type-sequence.
+//
+
+template <typename Types, typename NeverUsesBackupFlag>
+struct make_storage
+{
+private: // helpers, for metafunction result (below)
+
+    typedef typename mpl::eval_if<
+          NeverUsesBackupFlag
+        , mpl::identity< Types >
+        , mpl::push_front<
+              Types, backup_holder<void*>
+            >
+        >::type types;
+
+    typedef typename max_value<
+          types, mpl::sizeof_<mpl::_1>
+        >::type max_size;
+
+#if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x0551))
+
+    typedef typename max_value<
+          types, alignment_of<mpl::_1>
+        >::type max_alignment;
+
+#else // borland
+
+    // temporary workaround -- use maximal alignment
+    typedef mpl::size_t< -1 > max_alignment;
+
+#endif // borland workaround
+
+public: // metafunction result
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, <= 1300)
+
+    typedef ::boost::aligned_storage<
+          BOOST_MPL_AUX_VALUE_WKND(max_size)::value
+        , BOOST_MPL_AUX_VALUE_WKND(max_alignment)::value
+        > type;
+
+#else // MSVC7 and below
+
+    BOOST_STATIC_CONSTANT(std::size_t, msvc_max_size_c = max_size::value);
+    BOOST_STATIC_CONSTANT(std::size_t, msvc_max_alignment_c = max_alignment::value);
+
+    typedef ::boost::aligned_storage<
+          msvc_max_size_c
+        , msvc_max_alignment_c
+        > type;
+
+#endif // MSVC workaround
+
+};
+
+#if defined(BOOST_MPL_CFG_MSVC_60_ETI_BUG)
+
+template<>
+struct make_storage<int,int>
+{
+    typedef int type;
+};
+
+#endif // BOOST_MPL_CFG_MSVC_60_ETI_BUG workaround
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class destroyer
+//
+// Internal visitor that destroys the value it visits.
+//
+struct destroyer
+    : public static_visitor<>
+{
+public: // visitor interfaces
+
+    template <typename T>
+        BOOST_VARIANT_AUX_RETURN_VOID_TYPE
+    internal_visit(T& operand, int) const
+    {
+        operand.~T();
+
+#if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x0551))
+        operand; // suppresses warnings
+#endif
+
+        BOOST_VARIANT_AUX_RETURN_VOID;
+    }
+
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class template known_get
+//
+// Visitor that returns a reference to content of the specified type.
+//
+// Precondition: visited variant MUST contain logical content of type T.
+//
+template <typename T>
+class known_get
+    : public static_visitor<T&>
+{
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, < 1300)
+
+public: // visitor interface
+
+    T& operator()(T& operand) const
+    {
+        return operand;
+    }
+
+    template <typename U>
+    T& operator()(U&) const
+    {
+        // logical error to be here: see precondition above
+        BOOST_ASSERT(false);
+        return ::boost::detail::variant::forced_return< T& >();
+    }
+
+#else // MSVC6
+
+private: // helpers, for visitor interface (below)
+
+    T& execute(T& operand, mpl::true_) const
+    {
+        return operand;
+    }
+
+    template <typename U>
+    T& execute(U& operand, mpl::false_) const
+    {
+        // logical error to be here: see precondition above
+        BOOST_ASSERT(false);
+        return ::boost::detail::variant::forced_return< T& >();
+    }
+
+public: // visitor interface
+
+    template <typename U>
+    T& operator()(U& operand) const
+    {
+        typedef typename is_same< U,T >::type
+            U_is_T;
+
+        return execute(operand, U_is_T());
+    }
+
+#endif // MSVC6 workaround
+
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class copy_into
+//
+// Internal visitor that copies the value it visits into the given buffer.
+//
+class copy_into
+    : public static_visitor<>
+{
+private: // representation
+
+    void* storage_;
+
+public: // structors
+
+    explicit copy_into(void* storage)
+        : storage_(storage)
+    {
+    }
+
+public: // internal visitor interface
+
+    template <typename T>
+        BOOST_VARIANT_AUX_RETURN_VOID_TYPE
+    internal_visit(boost::detail::variant::backup_holder<T>& operand, long) const
+    {
+        new(storage_) T( operand.get() );
+        BOOST_VARIANT_AUX_RETURN_VOID;
+    }
+
+    template <typename T>
+        BOOST_VARIANT_AUX_RETURN_VOID_TYPE
+    internal_visit(const boost::detail::variant::backup_holder<T>& operand, long) const
+    {
+        new(storage_) T( operand.get() );
+        BOOST_VARIANT_AUX_RETURN_VOID;
+    }
+
+    template <typename T>
+        BOOST_VARIANT_AUX_RETURN_VOID_TYPE
+    internal_visit(const T& operand, int) const
+    {
+        new(storage_) T(operand);
+        BOOST_VARIANT_AUX_RETURN_VOID;
+    }
+
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class assign_storage
+//
+// Internal visitor that assigns the given storage (which must be a
+// constructed value of the same type) to the value it visits.
+//
+struct assign_storage
+    : public static_visitor<>
+{
+private: // representation
+
+    const void* rhs_storage_;
+
+public: // structors
+
+    explicit assign_storage(const void* rhs_storage)
+        : rhs_storage_(rhs_storage)
+    {
+    }
+
+public: // internal visitor interfaces
+
+    template <typename T>
+        BOOST_VARIANT_AUX_RETURN_VOID_TYPE
+    internal_visit(backup_holder<T>& lhs_content, long) const
+    {
+        lhs_content.get()
+            = static_cast< const backup_holder<T>* >(rhs_storage_)->get();
+        BOOST_VARIANT_AUX_RETURN_VOID;
+    }
+
+    template <typename T>
+        BOOST_VARIANT_AUX_RETURN_VOID_TYPE
+    internal_visit(const backup_holder<T>& lhs_content, long) const
+    {
+        lhs_content.get()
+            = static_cast< const backup_holder<T>* >(rhs_storage_)->get();
+        BOOST_VARIANT_AUX_RETURN_VOID;
+    }
+
+    template <typename T>
+        BOOST_VARIANT_AUX_RETURN_VOID_TYPE
+    internal_visit(T& lhs_content, int) const
+    {
+        // NOTE TO USER :
+        // Compile error here indicates one of variant's bounded types does
+        // not meet the requirements of the Assignable concept. Thus,
+        // variant is not Assignable.
+        //
+        // Hint: Are any of the bounded types const-qualified or references?
+        //
+        lhs_content = *static_cast< const T* >(rhs_storage_);
+        BOOST_VARIANT_AUX_RETURN_VOID;
+    }
+
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class direct_assigner
+//
+// Generic static visitor that: if and only if the visited value is of the
+// specified type, assigns the given value to the visited value and returns
+// true; else returns false.
+//
+template <typename T>
+class direct_assigner
+    : public static_visitor<bool>
+{
+private: // representation
+
+    T& rhs_;
+
+public: // structors
+
+    explicit direct_assigner(T& rhs)
+        : rhs_(rhs)
+    {
+    }
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, < 1300)
+
+public: // visitor interface
+
+    bool operator()(T& lhs)
+    {
+        lhs = rhs_;
+        return true;
+    }
+
+    template <typename U>
+    bool operator()(U&)
+    {
+        return false;
+    }
+
+#else // MSVC6
+
+private: // helpers, for visitor interface (below)
+
+    bool execute(T& lhs, mpl::true_)
+    {
+        lhs = rhs_;
+        return true;
+    }
+
+    template <typename U>
+    bool execute(U&, mpl::false_)
+    {
+        return false;
+    }
+
+public: // visitor interface
+
+    template <typename U>
+    bool operator()(U& lhs)
+    {
+        typedef typename is_same<U,T>::type U_is_T;
+        return execute(lhs, U_is_T());
+    }
+
+#endif // MSVC6 workaround
+
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class backup_assigner
+//
+// Internal visitor that "assigns" the given value to the visited value,
+// using backup to recover if the destroy-copy sequence fails.
+//
+// NOTE: This needs to be a friend of variant, as it needs access to
+// indicate_which, indicate_backup_which, etc.
+//
+template <typename Variant, typename RhsT>
+class backup_assigner
+    : public static_visitor<>
+{
+private: // representation
+
+    Variant& lhs_;
+    int rhs_which_;
+    const RhsT& rhs_content_;
+
+public: // structors
+
+    backup_assigner(Variant& lhs, int rhs_which, const RhsT& rhs_content)
+        : lhs_(lhs)
+        , rhs_which_(rhs_which)
+        , rhs_content_(rhs_content)
+    {
+    }
+
+private: // helpers, for visitor interface (below)
+
+    template <typename LhsT>
+    void backup_assign_impl(
+          LhsT& lhs_content
+        , mpl::true_// has_nothrow_move
+        )
+    {
+        // Move lhs content to backup...
+        LhsT backup_lhs_content(
+              ::boost::detail::variant::move(lhs_content)
+            ); // nothrow
+
+        // ...destroy lhs content...
+        lhs_content.~LhsT(); // nothrow
+
+        try
+        {
+            // ...and attempt to copy rhs content into lhs storage:
+            new(lhs_.storage_.address()) RhsT(rhs_content_);
+        }
+        catch (...)
+        {
+            // In case of failure, restore backup content to lhs storage...
+            new(lhs_.storage_.address())
+                LhsT(
+                      ::boost::detail::variant::move(backup_lhs_content)
+                    ); // nothrow
+
+            // ...and rethrow:
+            throw;
+        }
+
+        // In case of success, indicate new content type:
+        lhs_.indicate_which(rhs_which_); // nothrow
+    }
+
+    template <typename LhsT>
+    void backup_assign_impl(
+          LhsT& lhs_content
+        , mpl::false_// has_nothrow_move
+        )
+    {
+        // Backup lhs content...
+        LhsT* backup_lhs_ptr = new LhsT(lhs_content);
+
+        // ...destroy lhs content...
+        lhs_content.~LhsT(); // nothrow
+
+        try
+        {
+            // ...and attempt to copy rhs content into lhs storage:
+            new(lhs_.storage_.address()) RhsT(rhs_content_);
+        }
+        catch (...)
+        {
+            // In case of failure, copy backup pointer to lhs storage...
+            new(lhs_.storage_.address())
+                backup_holder<LhsT>( backup_lhs_ptr ); // nothrow
+
+            // ...indicate now using backup...
+            lhs_.indicate_backup_which( lhs_.which() ); // nothrow
+
+            // ...and rethrow:
+            throw;
+        }
+
+        // In case of success, indicate new content type...
+        lhs_.indicate_which(rhs_which_); // nothrow
+
+        // ...and delete backup:
+        delete backup_lhs_ptr; // nothrow
+    }
+
+public: // visitor interface
+
+    template <typename LhsT>
+        BOOST_VARIANT_AUX_RETURN_VOID_TYPE
+    internal_visit(LhsT& lhs_content, int)
+    {
+        typedef typename has_nothrow_move_constructor<LhsT>::type
+            nothrow_move;
+
+        backup_assign_impl( lhs_content, nothrow_move() );
+
+        BOOST_VARIANT_AUX_RETURN_VOID;
+    }
+
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class swap_with
+//
+// Visitor that swaps visited value with content of given variant.
+//
+// Precondition: Given variant MUST have same logical type as visited value.
+//
+template <typename Variant>
+struct swap_with
+    : public static_visitor<>
+{
+private: // representation
+
+    Variant& toswap_;
+
+public: // structors
+
+    explicit swap_with(Variant& toswap)
+        : toswap_(toswap)
+    {
+    }
+
+public: // internal visitor interfaces
+
+    template <typename T>
+    void operator()(T& operand) const
+    {
+        // Since the precondition ensures types are same, get T...
+        known_get<T> getter;
+        T& other = toswap_.apply_visitor(getter);
+
+        // ...and swap:
+        ::boost::detail::variant::move_swap( operand, other );
+    }
+
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class reflect
+//
+// Generic static visitor that performs a typeid on the value it visits.
+//
+class reflect
+    : public static_visitor<const std::type_info&>
+{
+public: // visitor interfaces
+
+    template <typename T>
+    const std::type_info& operator()(const T&) const
+    {
+        return typeid(T);
+    }
+
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class comparer
+//
+// Generic static visitor that compares the content of the given lhs variant
+// with the visited rhs content using Comp.
+//
+// Precondition: lhs.which() == rhs.which()
+//
+template <typename Variant, typename Comp>
+class comparer
+    : public static_visitor<bool>
+{
+private: // representation
+
+    const Variant& lhs_;
+
+public: // structors
+
+    explicit comparer(const Variant& lhs)
+        : lhs_(lhs)
+    {
+    }
+
+public: // visitor interfaces
+
+    template <typename T>
+    bool operator()(const T& rhs_content) const
+    {
+        // Since the precondition ensures lhs and rhs types are same, get T...
+        known_get<const T> getter;
+        const T& lhs_content = lhs_.apply_visitor(getter);
+
+        // ...and compare lhs and rhs contents:
+        return Comp()(lhs_content, rhs_content);
+    }
+
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class equal_comp
+//
+// Generic function object compares lhs with rhs using operator==.
+//
+struct equal_comp
+{
+    template <typename T>
+    bool operator()(const T& lhs, const T& rhs) const
+    {
+        return lhs == rhs;
+    }
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class less_comp
+//
+// Generic function object compares lhs with rhs using operator<.
+//
+struct less_comp
+{
+    template <typename T>
+    bool operator()(const T& lhs, const T& rhs) const
+    {
+        return lhs < rhs;
+    }
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// (detail) class template invoke_visitor
+//
+// Internal visitor that invokes the given visitor using:
+//  * for wrappers (e.g., recursive_wrapper), the wrapper's held value.
+//  * for all other values, the value itself.
+//
+template <typename Visitor>
+class invoke_visitor
+{
+private: // representation
+
+    Visitor& visitor_;
+
+public: // visitor typedefs
+
+    typedef typename Visitor::result_type
+        result_type;
+
+public: // structors
+
+    explicit invoke_visitor(Visitor& visitor)
+        : visitor_(visitor)
+    {
+    }
+
+#if !defined(BOOST_NO_VOID_RETURNS)
+
+public: // internal visitor interfaces
+
+    template <typename T>
+    result_type internal_visit(T& operand, int)
+    {
+        return visitor_(operand);
+    }
+
+#   if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x0564))
+    template <typename T>
+    result_type internal_visit(const T& operand, int)
+    {
+        return visitor_(operand);
+    }
+#   endif
+
+#else // defined(BOOST_NO_VOID_RETURNS)
+
+private: // helpers, for internal visitor interfaces (below)
+
+    template <typename T>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
+    visit_impl(T& operand, mpl::false_)
+    {
+        return visitor_(operand);
+    }
+
+    template <typename T>
+        BOOST_VARIANT_AUX_RETURN_VOID_TYPE
+    visit_impl(T& operand, mpl::true_)
+    {
+        visitor_(operand);
+        BOOST_VARIANT_AUX_RETURN_VOID;
+    }
+
+public: // internal visitor interfaces
+
+    template <typename T>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
+    internal_visit(T& operand, int)
+    {
+        typedef typename is_same<result_type, void>::type
+            has_void_result_type;
+
+        return visit_impl(operand, has_void_result_type());
+    }
+
+#endif // BOOST_NO_VOID_RETURNS) workaround
+
+public: // internal visitor interfaces, cont.
+
+    template <typename T>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
+    internal_visit(boost::recursive_wrapper<T>& operand, long)
+    {
+        return internal_visit( operand.get(), 1L );
+    }
+
+    template <typename T>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
+    internal_visit(const boost::recursive_wrapper<T>& operand, long)
+    {
+        return internal_visit( operand.get(), 1L );
+    }
+
+    template <typename T>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
+    internal_visit(boost::detail::reference_content<T>& operand, long)
+    {
+        return internal_visit( operand.get(), 1L );
+    }
+
+    template <typename T>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
+    internal_visit(const boost::detail::reference_content<T>& operand, long)
+    {
+        return internal_visit( operand.get(), 1L );
+    }
+
+    template <typename T>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
+    internal_visit(boost::detail::variant::backup_holder<T>& operand, long)
+    {
+        return internal_visit( operand.get(), 1L );
+    }
+
+    template <typename T>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
+    internal_visit(const boost::detail::variant::backup_holder<T>& operand, long)
+    {
+        return internal_visit( operand.get(), 1L );
+    }
+
+};
+
+}} // namespace detail::variant
+
+///////////////////////////////////////////////////////////////////////////////
+// class template variant (concept inspired by Andrei Alexandrescu)
+//
+// See docs and boost/variant/variant_fwd.hpp for more information.
+//
+template <
+      typename T0_
+    , BOOST_VARIANT_ENUM_SHIFTED_PARAMS(typename T)
+    >
+class variant
+{
+private: // helpers, for typedefs (below)
+
+    typedef variant wknd_self_t;
+
+    struct is_recursive_
+        : detail::variant::is_recursive_flag<T0_>
+    {
+    };
+
+    typedef typename mpl::eval_if<
+          is_recursive_
+        , T0_
+        , mpl::identity< T0_ >
+        >::type unwrapped_T0_;
+
+    struct is_sequence_based_
+        : detail::variant::is_over_sequence<unwrapped_T0_>
+    {
+    };
+
+#if !defined(BOOST_VARIANT_NO_TYPE_SEQUENCE_SUPPORT)
+
+private: // helpers, for typedefs (below)
+
+    typedef typename mpl::eval_if<
+          is_sequence_based_
+        , unwrapped_T0_ // over_sequence<...>::type
+        , detail::variant::make_variant_list<
+              unwrapped_T0_
+            , BOOST_VARIANT_ENUM_SHIFTED_PARAMS(T)
+            >
+        >::type specified_types;
+
+    BOOST_STATIC_ASSERT((
+          ::boost::mpl::not_< mpl::empty<specified_types> >::value
+        ));
+
+    typedef typename mpl::eval_if<
+          is_recursive_
+        , mpl::transform<
+              specified_types
+            , mpl::protect<
+                  detail::variant::quoted_enable_recursive<wknd_self_t>
+                >
+            >
+        , mpl::identity< specified_types >
+        >::type recursive_enabled_types;
+
+public: // public typedefs
+
+    typedef typename mpl::transform<
+          recursive_enabled_types
+        , unwrap_recursive<mpl::_1>
+        >::type types;
+
+private: // internal typedefs
+
+    typedef typename mpl::transform<
+          recursive_enabled_types
+        , mpl::protect< detail::make_reference_content<> >
+        >::type internal_types;
+
+    typedef typename mpl::front<
+          internal_types
+        >::type internal_T0;
+
+#else // defined(BOOST_VARIANT_NO_TYPE_SEQUENCE_SUPPORT)
+
+private: // helpers, for typedefs (below)
+
+    typedef unwrapped_T0_ T0;
+
+    #define BOOST_VARIANT_AUX_ENABLE_RECURSIVE_TYPEDEFS(z,N,_) \
+        typedef typename mpl::eval_if< \
+              is_recursive_ \
+            , detail::variant::enable_recursive< \
+                  BOOST_PP_CAT(T,N) \
+                , wknd_self_t \
+                > \
+            , mpl::identity< BOOST_PP_CAT(T,N) > \
+            >::type BOOST_PP_CAT(recursive_enabled_T,N); \
+        /**/
+
+    BOOST_PP_REPEAT(
+          BOOST_VARIANT_LIMIT_TYPES
+        , BOOST_VARIANT_AUX_ENABLE_RECURSIVE_TYPEDEFS
+        , _
+        )
+
+    #undef BOOST_VARIANT_AUX_ENABLE_RECURSIVE_TYPEDEFS
+
+    #define BOOST_VARIANT_AUX_UNWRAP_RECURSIVE_TYPEDEFS(z,N,_) \
+        typedef typename unwrap_recursive< \
+              BOOST_PP_CAT(recursive_enabled_T,N) \
+            >::type BOOST_PP_CAT(public_T,N); \
+        /**/
+
+    BOOST_PP_REPEAT(
+          BOOST_VARIANT_LIMIT_TYPES
+        , BOOST_VARIANT_AUX_UNWRAP_RECURSIVE_TYPEDEFS
+        , _
+        )
+
+    #undef BOOST_VARIANT_AUX_UNWRAP_RECURSIVE_TYPEDEFS
+
+public: // public typedefs
+
+    typedef typename detail::variant::make_variant_list<
+          BOOST_VARIANT_ENUM_PARAMS(public_T)
+        >::type types;
+
+private: // helpers, for internal typedefs (below)
+
+    #define BOOST_VARIANT_AUX_MAKE_REFERENCE_CONTENT_TYPEDEFS(z,N,_) \
+        typedef detail::make_reference_content< \
+              BOOST_PP_CAT(recursive_enabled_T,N) \
+            >::type BOOST_PP_CAT(internal_T,N); \
+        /**/
+
+    BOOST_PP_REPEAT(
+          BOOST_VARIANT_LIMIT_TYPES
+        , BOOST_VARIANT_AUX_MAKE_REFERENCE_CONTENT_TYPEDEFS
+        , _
+        )
+
+    #undef BOOST_VARIANT_AUX_MAKE_REFERENCE_CONTENT_TYPEDEFS
+
+private: // internal typedefs
+
+    typedef typename detail::variant::make_variant_list<
+          BOOST_VARIANT_ENUM_PARAMS(internal_T)
+        >::type internal_types;
+
+private: // static precondition assertions
+
+    // NOTE TO USER :
+    // variant< type-sequence > syntax is not supported on this compiler!
+    //
+    BOOST_MPL_ASSERT_NOT(( is_sequence_based_ ));
+
+#endif // BOOST_VARIANT_NO_TYPE_SEQUENCE_SUPPORT workaround
+
+private: // helpers, for representation (below)
+
+    typedef typename detail::variant::find_fallback_type<
+          internal_types
+        >::type fallback_type_result_;
+
+    typedef typename fallback_type_result_::first
+        fallback_type_index_;
+    typedef typename fallback_type_result_::second
+        fallback_type_;
+
+    struct has_fallback_type_
+        : mpl::not_<
+              is_same< fallback_type_, detail::variant::no_fallback_type >
+            >
+    {
+    };
+
+    typedef has_fallback_type_
+        never_uses_backup_flag;
+
+    typedef typename detail::variant::make_storage<
+          internal_types, never_uses_backup_flag
+        >::type storage_t;
+
+private: // helpers, for representation (below)
+
+    // which_ on:
+    // * [0,  size<internal_types>) indicates stack content
+    // * [-size<internal_types>, 0) indicates pointer to heap backup
+    // if which_ >= 0:
+    // * then which() -> which_
+    // * else which() -> -(which_ + 1)
+
+#if !defined(BOOST_VARIANT_MINIMIZE_SIZE)
+
+    typedef int which_t;
+
+#else // defined(BOOST_VARIANT_MINIMIZE_SIZE)
+
+    // [if O1_size available, then attempt which_t size optimization...]
+    // [select signed char if fewer than SCHAR_MAX types, else signed int:]
+    typedef typename mpl::eval_if<
+          mpl::equal_to< mpl::O1_size<internal_types>, mpl::long_<-1> >
+        , mpl::identity< int >
+        , mpl::if_<
+              mpl::less< mpl::O1_size<internal_types>, mpl::int_<SCHAR_MAX> >
+            , signed char
+            , int
+            >
+        >::type which_t;
+
+#endif // BOOST_VARIANT_MINIMIZE_SIZE switch
+
+// representation -- private when possible
+#if !defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS)
+    private:
+#else
+    public:
+#endif
+
+    which_t which_;
+    storage_t storage_;
+
+    void indicate_which(int which)
+    {
+        which_ = static_cast<which_t>( which );
+    }
+
+    void indicate_backup_which(int which)
+    {
+        which_ = static_cast<which_t>( -(which + 1) );
+    }
+
+private: // helpers, for queries (below)
+
+    bool using_backup() const
+    {
+        return which_ < 0;
+    }
+
+public: // queries
+
+    int which() const
+    {
+        // If using heap backup...
+        if (using_backup())
+            // ...then return adjusted which_:
+            return -(which_ + 1);
+
+        // Otherwise, return which_ directly:
+        return which_;
+    }
+
+private: // helpers, for structors (below)
+
+    struct initializer
+        : BOOST_VARIANT_AUX_INITIALIZER_T(
+              recursive_enabled_types, recursive_enabled_T
+            )
+    {
+    };
+
+    void destroy_content()
+    {
+        detail::variant::destroyer visitor;
+        this->internal_apply_visitor(visitor);
+    }
+
+public: // structors
+
+    ~variant()
+    {
+        destroy_content();
+    }
+
+    variant()
+    {
+        // NOTE TO USER :
+        // Compile error from here indicates that the first bound
+        // type is not default-constructible, and so variant cannot
+        // support its own default-construction.
+        //
+        new( storage_.address() ) internal_T0();
+        indicate_which(0); // zero is the index of the first bounded type
+    }
+
+private: // helpers, for structors, cont. (below)
+
+    class convert_copy_into
+        : public static_visitor<int>
+    {
+    private: // representation
+
+        void* storage_;
+
+    public: // structors
+
+        explicit convert_copy_into(void* storage)
+            : storage_(storage)
+        {
+        }
+
+    public: // internal visitor interfaces (below)
+
+        template <typename T>
+        int internal_visit(T& operand, int) const
+        {
+            // NOTE TO USER :
+            // Compile error here indicates one of the source variant's types 
+            // cannot be unambiguously converted to the destination variant's
+            // types (or that no conversion exists).
+            //
+            return initializer::initialize(storage_, operand);
+        }
+
+#   if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x0564))
+        template <typename T>
+        result_type internal_visit(const T& operand, int) const
+        {
+            return initializer::initialize(storage_, operand);
+        }
+#   endif
+
+        template <typename T>
+        int internal_visit(boost::detail::reference_content<T>& operand, long) const
+        {
+            return internal_visit( operand.get(), 1L );
+        }
+
+        template <typename T>
+        int internal_visit(const boost::detail::reference_content<T>& operand, long) const
+        {
+            return internal_visit( operand.get(), 1L );
+        }
+
+        template <typename T>
+        int internal_visit(boost::detail::variant::backup_holder<T>& operand, long) const
+        {
+            return internal_visit( operand.get(), 1L );
+        }
+
+        template <typename T>
+        int internal_visit(const boost::detail::variant::backup_holder<T>& operand, long) const
+        {
+            return internal_visit( operand.get(), 1L );
+        }
+
+        template <typename T>
+        int internal_visit(boost::recursive_wrapper<T>& operand, long) const
+        {
+            return internal_visit( operand.get(), 1L );
+        }
+
+        template <typename T>
+        int internal_visit(const boost::recursive_wrapper<T>& operand, long) const
+        {
+            return internal_visit( operand.get(), 1L );
+        }
+
+    };
+
+    friend class convert_copy_into;
+
+private: // helpers, for structors, below 
+
+    template <typename T>
+    void convert_construct(
+          T& operand
+        , int
+        , mpl::false_ = mpl::false_() // is_foreign_variant
+        )
+    {
+        // NOTE TO USER :
+        // Compile error here indicates that the given type is not 
+        // unambiguously convertible to one of the variant's types
+        // (or that no conversion exists).
+        //
+        indicate_which(
+              initializer::initialize(
+                  storage_.address()
+                , operand
+                )
+            );
+    }
+
+    template <typename Variant>
+    void convert_construct(
+          Variant& operand
+        , long
+        , mpl::true_// is_foreign_variant
+        )
+    {
+        convert_copy_into visitor(storage_.address());
+        indicate_which(
+              operand.internal_apply_visitor(visitor)
+            );
+    }
+
+    template <typename Variant>
+    void convert_construct_variant(Variant& operand)
+    {
+        // [Determine if the given variant is itself a bounded type, or if its
+        //  content needs to be converted (i.e., it is a 'foreign' variant):]
+        //
+
+        typedef typename mpl::find_if<
+              types
+            , is_same<
+                  add_const<mpl::_1>
+                , const Variant
+                >
+            >::type found_it;
+
+        typedef typename mpl::end<types>::type not_found;
+        typedef typename is_same<
+              found_it, not_found
+            >::type is_foreign_variant;
+
+        // Convert construct from operand:
+        convert_construct(
+              operand, 1L
+            , is_foreign_variant()
+            );
+    }
+
+    template <BOOST_VARIANT_ENUM_PARAMS(typename U)>
+    void convert_construct(
+          boost::variant<BOOST_VARIANT_ENUM_PARAMS(U)>& operand
+        , long
+        )
+    {
+        convert_construct_variant(operand);
+    }
+
+    template <BOOST_VARIANT_ENUM_PARAMS(typename U)>
+    void convert_construct(
+          const boost::variant<BOOST_VARIANT_ENUM_PARAMS(U)>& operand
+        , long
+        )
+    {
+        convert_construct_variant(operand);    
+    }
+
+public: // structors, cont.
+
+#if !defined(BOOST_VARIANT_AUX_BROKEN_CONSTRUCTOR_TEMPLATE_ORDERING)
+
+    template <typename T>
+    variant(const T& operand)
+    {
+        convert_construct(operand, 1L);
+    }
+
+    template <typename T>
+    variant(T& operand)
+    {
+        convert_construct(operand, 1L);
+    }
+
+#elif defined(BOOST_VARIANT_AUX_HAS_CONSTRUCTOR_TEMPLATE_ORDERING_SFINAE_WKND)
+
+    // For compilers that cannot distinguish between T& and const T& in
+    // template constructors, but do fully support SFINAE, we can workaround:
+
+    template <typename T>
+    variant(const T& operand)
+    {
+        convert_construct(operand, 1L);
+    }
+
+    template <typename T>
+    variant(
+          T& operand
+        , typename enable_if<
+              mpl::not_< is_const<T> >
+            , void
+            >::type* = 0
+        )
+    {
+        convert_construct(operand, 1L);
+    }
+
+#else // !defined(BOOST_VARIANT_AUX_HAS_CONSTRUCTOR_TEMPLATE_ORDERING_SFINAE_WKND)
+
+    // For compilers that cannot distinguish between T& and const T& in
+    // template constructors, and do NOT support SFINAE, we can't workaround:
+
+    template <typename T>
+    variant(const T& operand)
+    {
+        convert_construct(operand, 1L);
+    }
+
+#endif // BOOST_VARIANT_AUX_BROKEN_CONSTRUCTOR_TEMPLATE_ORDERING workarounds
+
+public: // structors, cont.
+
+    // [MSVC6 requires copy constructor appear after template constructors]
+    variant(const variant& operand)
+    {
+        // Copy the value of operand into *this...
+        detail::variant::copy_into visitor( storage_.address() );
+        operand.internal_apply_visitor(visitor);
+
+        // ...and activate the *this's primary storage on success:
+        indicate_which(operand.which());
+    }
+
+private: // helpers, for modifiers (below)
+
+#   if !defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS)
+    template <typename Variant, typename RhsT>
+    friend class detail::variant::backup_assigner;
+#   endif
+
+    // class assigner
+    //
+    // Internal visitor that "assigns" the visited value to the given variant
+    // by appropriate destruction and copy-construction.
+    //
+
+    class assigner
+        : public static_visitor<>
+    {
+    private: // representation
+
+        variant& lhs_;
+        int rhs_which_;
+
+    public: // structors
+
+        assigner(variant& lhs, int rhs_which)
+            : lhs_(lhs)
+            , rhs_which_(rhs_which)
+        {
+        }
+
+    private: // helpers, for internal visitor interface (below)
+
+        template <typename RhsT, typename B1, typename B2>
+        void assign_impl(
+              const RhsT& rhs_content
+            , mpl::true_// has_nothrow_copy
+            , B1// has_nothrow_move_constructor
+            , B2// has_fallback_type
+            )
+        {
+            // Destroy lhs's content...
+            lhs_.destroy_content(); // nothrow
+
+            // ...copy rhs content into lhs's storage...
+            new(lhs_.storage_.address())
+                RhsT( rhs_content ); // nothrow
+
+            // ...and indicate new content type:
+            lhs_.indicate_which(rhs_which_); // nothrow
+        }
+
+        template <typename RhsT, typename B>
+        void assign_impl(
+              const RhsT& rhs_content
+            , mpl::false_// has_nothrow_copy
+            , mpl::true_// has_nothrow_move_constructor
+            , B// has_fallback_type
+            )
+        {
+            // Attempt to make a temporary copy (so as to move it below)...
+            RhsT temp(rhs_content);
+
+            // ...and upon success destroy lhs's content...
+            lhs_.destroy_content(); // nothrow
+
+            // ...move the temporary copy into lhs's storage...
+            new(lhs_.storage_.address())
+                RhsT( detail::variant::move(temp) ); // nothrow
+
+            // ...and indicate new content type:
+            lhs_.indicate_which(rhs_which_); // nothrow
+        }
+
+        template <typename RhsT>
+        void assign_impl(
+              const RhsT& rhs_content
+            , mpl::false_// has_nothrow_copy
+            , mpl::false_// has_nothrow_move_constructor
+            , mpl::true_// has_fallback_type
+            )
+        {
+            // Destroy lhs's content...
+            lhs_.destroy_content(); // nothrow
+
+            try
+            {
+                // ...and attempt to copy rhs's content into lhs's storage:
+                new(lhs_.storage_.address())
+                    RhsT( rhs_content );
+            }
+            catch (...)
+            {
+                // In case of failure, default-construct fallback type in lhs's storage...
+                new (lhs_.storage_.address())
+                    fallback_type_; // nothrow
+
+                // ...indicate construction of fallback type...
+                lhs_.indicate_which(
+                      BOOST_MPL_AUX_VALUE_WKND(fallback_type_index_)::value
+                    ); // nothrow
+
+                // ...and rethrow:
+                throw;
+            }
+
+            // In the event of success, indicate new content type:
+            lhs_.indicate_which(rhs_which_); // nothrow
+        }
+
+        template <typename RhsT>
+        void assign_impl(
+              const RhsT& rhs_content
+            , mpl::false_// has_nothrow_copy
+            , mpl::false_// has_nothrow_move_constructor
+            , mpl::false_// has_fallback_type
+            )
+        {
+            detail::variant::backup_assigner<wknd_self_t, RhsT>
+                visitor(lhs_, rhs_which_, rhs_content);
+            lhs_.internal_apply_visitor(visitor);
+        }
+
+    public: // internal visitor interfaces
+
+        template <typename RhsT>
+            BOOST_VARIANT_AUX_RETURN_VOID_TYPE
+        internal_visit(const RhsT& rhs_content, int)
+        {
+            typedef typename has_nothrow_copy<RhsT>::type
+                nothrow_copy;
+            typedef typename mpl::or_< // reduces compile-time
+                  nothrow_copy
+                , detail::variant::has_nothrow_move_constructor<RhsT>
+                >::type nothrow_move_constructor;
+
+            assign_impl(
+                  rhs_content
+                , nothrow_copy()
+                , nothrow_move_constructor()
+                , has_fallback_type_()
+                );
+
+            BOOST_VARIANT_AUX_RETURN_VOID;
+        }
+
+    };
+
+    friend class assigner;
+
+    void variant_assign(const variant& rhs)
+    {
+        // If the contained types are EXACTLY the same...
+        if (which_ == rhs.which_)
+        {
+            // ...then assign rhs's storage to lhs's content:
+            detail::variant::assign_storage visitor(rhs.storage_.address());
+            this->internal_apply_visitor(visitor);
+        }
+        else
+        {
+            // Otherwise, perform general (copy-based) variant assignment:
+            assigner visitor(*this, rhs.which());
+            rhs.internal_apply_visitor(visitor); 
+        }
+    }
+
+private: // helpers, for modifiers (below)
+
+    template <typename T>
+    void assign(const T& rhs)
+    {
+        // If direct T-to-T assignment is not possible...
+        detail::variant::direct_assigner<const T> direct_assign(rhs);
+        if (this->apply_visitor(direct_assign) == false)
+        {
+            // ...then convert rhs to variant and assign:
+            //
+            // While potentially inefficient, the following construction of a
+            // variant allows T as any type convertible to one of the bounded
+            // types without excessive code redundancy.
+            //
+            variant temp(rhs);
+            variant_assign( detail::variant::move(temp) );
+        }
+    }
+
+public: // modifiers
+
+    template <typename T>
+    variant& operator=(const T& rhs)
+    {
+        assign(rhs);
+        return *this;
+    }
+
+    // [MSVC6 requires copy assign appear after templated operator=]
+    variant& operator=(const variant& rhs)
+    {
+        variant_assign(rhs);
+        return *this;
+    }
+
+    void swap(variant& rhs)
+    {
+        // If the contained types are the same...
+        if (which() == rhs.which())
+        {
+            // ...then swap the values directly:
+            detail::variant::swap_with<variant> visitor(rhs);
+            this->apply_visitor(visitor);
+        }
+        else
+        {
+            // ...otherwise, perform general variant swap:
+            variant tmp( detail::variant::move(rhs) );
+            rhs = detail::variant::move(*this);
+            *this = detail::variant::move(tmp);
+        }
+    }
+
+public: // queries
+
+    //
+    // NOTE: member which() defined above.
+    //
+
+    bool empty() const
+    {
+        return false;
+    }
+
+    const std::type_info& type() const
+    {
+        detail::variant::reflect visitor;
+        return this->apply_visitor(visitor);
+    }
+
+public: // prevent comparison with foreign types
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, <= 1300)
+
+#   define BOOST_VARIANT_AUX_FAIL_COMPARISON_RETURN_TYPE \
+    void
+
+#else // MSVC7
+
+    //
+    // MSVC7 gives error about return types for above being different than
+    // the true comparison operator overloads:
+    //
+
+#   define BOOST_VARIANT_AUX_FAIL_COMPARISON_RETURN_TYPE \
+    bool
+
+#endif // MSVC7 workaround
+
+    template <typename U>
+        BOOST_VARIANT_AUX_FAIL_COMPARISON_RETURN_TYPE
+    operator==(const U&) const
+    {
+        BOOST_STATIC_ASSERT( false && sizeof(U) );
+    }
+
+    template <typename U>
+        BOOST_VARIANT_AUX_FAIL_COMPARISON_RETURN_TYPE
+    operator<(const U&) const
+    {
+        BOOST_STATIC_ASSERT( false && sizeof(U) );
+    }
+
+public: // comparison operators
+
+    // [MSVC6 requires these operators appear after template operators]
+
+    bool operator==(const variant& rhs) const
+    {
+        if (this->which() != rhs.which())
+            return false;
+
+        detail::variant::comparer<
+              variant, detail::variant::equal_comp
+            > visitor(*this);
+        return rhs.apply_visitor(visitor);
+    }
+
+    bool operator<(const variant& rhs) const
+    {
+        //
+        // Dirk Schreib suggested this collating order.
+        //
+
+        if (this->which() != rhs.which())
+            return this->which() < rhs.which();
+
+        detail::variant::comparer<
+              variant, detail::variant::less_comp
+            > visitor(*this);
+        return rhs.apply_visitor(visitor);
+    }
+
+// helpers, for visitation support (below) -- private when possible
+#if !defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS)
+
+    template < BOOST_VARIANT_ENUM_PARAMS(typename U) >
+    friend class variant;
+
+private:
+
+#else// defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS)
+
+public:
+
+#endif// !defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS)
+
+    template <typename Visitor, typename VoidPtrCV>
+    static
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(
+              typename Visitor::result_type
+            )
+    internal_apply_visitor_impl(
+          int internal_which
+        , int logical_which
+        , Visitor& visitor
+        , VoidPtrCV storage
+        )
+    {
+        typedef mpl::int_<0> first_which;
+        typedef typename mpl::begin<internal_types>::type first_it;
+        typedef typename mpl::end<internal_types>::type last_it;
+
+        typedef detail::variant::visitation_impl_step<
+              first_it, last_it
+            > first_step;
+
+        return detail::variant::visitation_impl(
+              internal_which, logical_which
+            , visitor, storage, mpl::false_()
+            , never_uses_backup_flag()
+            , static_cast<first_which*>(0), static_cast<first_step*>(0)
+            );
+    }
+
+    template <typename Visitor>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(
+              typename Visitor::result_type
+            )
+    internal_apply_visitor(Visitor& visitor)
+    {
+        return internal_apply_visitor_impl(
+              which_, which(), visitor, storage_.address()
+            );
+    }
+
+    template <typename Visitor>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(
+              typename Visitor::result_type
+            )
+    internal_apply_visitor(Visitor& visitor) const
+    {
+        return internal_apply_visitor_impl(
+              which_, which(), visitor, storage_.address()
+            );
+    }
+
+public: // visitation support
+
+    template <typename Visitor>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(
+              typename Visitor::result_type
+            )
+    apply_visitor(Visitor& visitor)
+    {
+        detail::variant::invoke_visitor<Visitor> invoker(visitor);
+        return this->internal_apply_visitor(invoker);
+    }
+
+    template <typename Visitor>
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(
+              typename Visitor::result_type
+            )
+    apply_visitor(Visitor& visitor) const
+    {
+        detail::variant::invoke_visitor<Visitor> invoker(visitor);
+        return this->internal_apply_visitor(invoker);
+    }
+
+}; // class variant
+
+///////////////////////////////////////////////////////////////////////////////
+// metafunction make_variant_over
+//
+// See docs and boost/variant/variant_fwd.hpp for more information.
+//
+template <typename Types>
+struct make_variant_over
+{
+private: // precondition assertions
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, <= 1300)
+    BOOST_STATIC_ASSERT(( ::boost::mpl::is_sequence<Types>::value ));
+#endif
+
+public: // metafunction result
+
+    typedef variant<
+          detail::variant::over_sequence< Types >
+        > type;
+
+};
+
+///////////////////////////////////////////////////////////////////////////////
+// function template swap
+//
+// Swaps two variants of the same type (i.e., identical specification).
+//
+template < BOOST_VARIANT_ENUM_PARAMS(typename T) >
+inline void swap(
+      variant< BOOST_VARIANT_ENUM_PARAMS(T) >& lhs
+    , variant< BOOST_VARIANT_ENUM_PARAMS(T) >& rhs
+    )
+{
+    lhs.swap(rhs);
+}
+
+} // namespace boost
+
+// implementation additions
+#include "boost/variant/detail/variant_io.hpp"
+
+#endif // BOOST_VARIANT_VARIANT_HPP