boost/iostreams/operations_fwd.hpp

0001 // (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
0002 // (C) Copyright 2003-2007 Jonathan Turkanis
0003 // Distributed under the Boost Software License, Version 1.0. (See accompanying
0004 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
0005
0006 // See http://www.boost.org/libs/iostreams for documentation.
0007
0008 #ifndef BOOST_IOSTREAMS_OPERATIONS_FWD_HPP_INCLUDED
0009 #define BOOST_IOSTREAMS_OPERATIONS_FWD_HPP_INCLUDED
0010
0011 #if defined(_MSC_VER)
0012 # pragma once
0013 #endif
0014
0015 #include <boost/mpl/not.hpp>
0016 #include <boost/type_traits/is_base_and_derived.hpp>
0017
0018 namespace boost { namespace iostreams {
0019
0020 template<typename T>
0021 struct operations;
0022
0023 namespace detail {
0024
0025 struct custom_tag { };
0026
0027 template<typename T>
0028 struct is_custom
0029     : mpl::not_<
0030           is_base_and_derived< custom_tag, operations<T> >
0031       >
0032     { };
0033
0034 } // End namespace detail.
0035
0036 template<typename T>
0037 struct operations : detail::custom_tag { };
0038
0039 } } // End namespaces iostreams, boost.
0040
0041 #endif // #ifndef BOOST_IOSTREAMS_OPERATIONS_FWD_HPP_INCLUDED //--------------//