text: 
  #ifndef BOOST_MPL_AUX_MSVC_IS_CLASS_HPP_INCLUDED
  #define BOOST_MPL_AUX_MSVC_IS_CLASS_HPP_INCLUDED
  
  // Copyright Aleksey Gurtovoy 2002-2004
  //
  // 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)
  //
  // See http://www.boost.org/libs/mpl for documentation.
  
  // $Source$
  // $Date: 2004-09-28 09:56:59 -0400 (Tue, 28 Sep 2004) $
  // $Revision: 25453 $
  
  #include <boost/mpl/if.hpp>
  #include <boost/mpl/bool.hpp>
  #include <boost/mpl/aux_/type_wrapper.hpp>
  #include <boost/mpl/aux_/yes_no.hpp>
  
  #include <boost/type_traits/is_reference.hpp>
  
  namespace boost { namespace mpl { namespace aux {
  
  template< typename T > struct is_class_helper
  {
      typedef int (T::* type)();
  };
  
  // MSVC 6.x-specific lightweight 'is_class' implementation; 
  // Distinguishing feature: does not instantiate the type being tested.
  template< typename T >
  struct msvc_is_class_impl
  {
      template< typename U>
      static yes_tag  test(type_wrapper<U>*, /*typename*/ is_class_helper<U>::type = 0);
      static no_tag   test(void const volatile*, ...);
  
      enum { value = sizeof(test((type_wrapper<T>*)0)) == sizeof(yes_tag) };
      typedef bool_<value> type;
  };
  
  // agurt, 17/sep/04: have to check for 'is_reference' upfront to avoid ICEs in
  // complex metaprograms
  template< typename T >
  struct msvc_is_class
      : if_<
            is_reference<T>
          , false_
          , msvc_is_class_impl<T>
          >::type
  {
  };
  
  }}}
  
  #endif // BOOST_MPL_AUX_MSVC_IS_CLASS_HPP_INCLUDED
  