Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

boost/is_placeholder.hpp

#ifndef BOOST_IS_PLACEHOLDER_HPP_INCLUDED
#define BOOST_IS_PLACEHOLDER_HPP_INCLUDED

// MS compatible compilers support #pragma once

#if defined( _MSC_VER ) && ( _MSC_VER >= 1020 )
# pragma once
#endif


//  is_placeholder.hpp - TR1 is_placeholder metafunction
//
//  Copyright (c) 2006 Peter Dimov
//
//  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


namespace boost
{

template< class T > struct is_placeholder
{
    enum _vt { value = 0 };
};

} // namespace boost

#endif // #ifndef BOOST_IS_PLACEHOLDER_HPP_INCLUDED