mpl/math/is_even.hpp

0001
0002 #ifndef BOOST_MPL_MATH_IS_EVEN_HPP_INCLUDED
0003 #define BOOST_MPL_MATH_IS_EVEN_HPP_INCLUDED
0004
0005 // Copyright Aleksey Gurtovoy 2000-2004
0006 //
0007 // Distributed under the Boost Software License, Version 1.0.
0008 // (See accompanying file LICENSE_1_0.txt or copy at
0009 // http://www.boost.org/LICENSE_1_0.txt)
0010 //
0011 // See http://www.boost.org/libs/mpl for documentation.
0012
0013 // $Id$
0014 // $Date$
0015 // $Revision$
0016
0017 #include <boost/mpl/bool.hpp>
0018 #include <boost/mpl/aux_/na_spec.hpp>
0019 #include <boost/mpl/aux_/lambda_support.hpp>
0020 #include <boost/mpl/aux_/config/msvc.hpp>
0021 #include <boost/mpl/aux_/config/workaround.hpp>
0022
0023 namespace boost { namespace mpl {
0024
0025 #if BOOST_WORKAROUND(BOOST_MSVC, <= 1300)
0026 namespace aux
0027 {
0028   template <class N>
0029   struct is_even_base
0030   {
0031       enum { value = (N::value % 2) == 0 };
0032       typedef bool_<value> type;
0033   };
0034 }
0035 #endif
0036
0037 template<
0038       typename BOOST_MPL_AUX_NA_PARAM(N)
0039     >
0040 struct is_even
0041 #if BOOST_WORKAROUND(BOOST_MSVC, <= 1300)
0042   : aux::is_even_base<N>::type
0043 #else
0044   : bool_<((N::value % 2) == 0)>
0045 #endif
0046 {
0047     BOOST_MPL_AUX_LAMBDA_SUPPORT(1,is_even,(N))
0048 };
0049
0050 BOOST_MPL_AUX_NA_SPEC(1, is_even)
0051
0052 }}
0053
0054 #endif // BOOST_MPL_MATH_IS_EVEN_HPP_INCLUDED