Chris@16: ////////////////////////////////////////////////////////////////////
Chris@16: //
Chris@16: // Copyright Vicente J. Botet Escriba 2010
Chris@16: //
Chris@101: // Distributed under the Boost Software License, Version 1.0.
Chris@101: // (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //
Chris@16: // See http://www.boost.org/libs/mpl for documentation.
Chris@16: //
Chris@16: ////////////////////////////////////////////////////////////////////
Chris@16: #ifndef BOOST_MPL_SIGN_HPP_INCLUDED
Chris@16: #define BOOST_MPL_SIGN_HPP_INCLUDED
Chris@16: 
Chris@16: #include <boost/mpl/integral_c.hpp>
Chris@16: #include <boost/mpl/aux_/na_spec.hpp>
Chris@16: #include <boost/mpl/aux_/lambda_support.hpp>
Chris@16: #include <boost/mpl/aux_/config/integral.hpp>
Chris@16: #include <boost/mpl/aux_/config/static_constant.hpp>
Chris@16: 
Chris@16: #if    !defined(BOOST_MPL_CFG_NO_NESTED_VALUE_ARITHMETIC_2) \
Chris@16:     && !defined(BOOST_MPL_PREPROCESSING_MODE) \
Chris@101:     && !defined(__CUDACC__) \
Chris@16:     && ( defined(BOOST_MSVC) \
Chris@16:         || BOOST_WORKAROUND(__EDG_VERSION__, <= 238) \
Chris@16:         )
Chris@16: 
Chris@16: #   define BOOST_MPL_CFG_NO_NESTED_VALUE_ARITHMETIC_2
Chris@16: 
Chris@16: #endif
Chris@16: 
Chris@16: namespace boost { namespace mpl {
Chris@16: 
Chris@16: template< typename Tag > struct sign_impl;
Chris@16: 
Chris@16: template< typename T > struct sign_tag
Chris@16: {
Chris@16:     typedef typename T::tag type;
Chris@16: };
Chris@16: 
Chris@16: template<
Chris@16:       typename BOOST_MPL_AUX_NA_PARAM(N)
Chris@16:     >
Chris@16: struct sign
Chris@16:     : sign_impl<
Chris@16:           typename sign_tag<N>::type
Chris@16:         >::template apply<N>::type
Chris@16: {
Chris@16:     BOOST_MPL_AUX_LAMBDA_SUPPORT(1, sign, (N))
Chris@16: };
Chris@16: 
Chris@16: BOOST_MPL_AUX_NA_SPEC(1, sign)
Chris@16: 
Chris@16: template<
Chris@16:       typename T
Chris@16:     , T n1
Chris@16:     >
Chris@16: struct sign_c
Chris@16:     : sign<integral_c<T,n1> >
Chris@16: {
Chris@16: };
Chris@16: 
Chris@16: #if defined(BOOST_MPL_CFG_NO_NESTED_VALUE_ARITHMETIC_2)
Chris@16: namespace aux {
Chris@16: template< typename T, T n > struct sign_wknd
Chris@16: {
Chris@16:     BOOST_STATIC_CONSTANT(T, value = (n == 0 ? 0 : (n < 0 ? -1 : 1)));
Chris@16:     typedef integral_c<T,value> type;
Chris@16: };
Chris@16: }
Chris@16: #endif
Chris@16: 
Chris@16: template<>
Chris@16: struct sign_impl<integral_c_tag>
Chris@16: {
Chris@16: #if defined(BOOST_MPL_CFG_NO_NESTED_VALUE_ARITHMETIC_2)
Chris@16:     template< typename N > struct apply
Chris@16:         : aux::sign_wknd< typename N::value_type, N::value >
Chris@16: #else
Chris@16:     template< typename N > struct apply
Chris@16:         : integral_c< typename N::value_type, (N::value == 0 ? 0 : (N::value < 0 ? -1 : 1)) >
Chris@101: #endif
Chris@16:     {
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: }}
Chris@16: 
Chris@16: #endif // BOOST_MPL_SIGN_HPP_INCLUDED