| //////////////////////////////////////////////////////////////////// |
| // |
| // Copyright Vicente J. Botet Escriba 2010 |
| // |
| // 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. |
| // |
| //////////////////////////////////////////////////////////////////// |
| #ifndef BOOST_MPL_SIGN_HPP_INCLUDED |
| #define BOOST_MPL_SIGN_HPP_INCLUDED |
| |
| #include <boost/mpl/integral_c.hpp> |
| #include <boost/mpl/aux_/na_spec.hpp> |
| #include <boost/mpl/aux_/lambda_support.hpp> |
| #include <boost/mpl/aux_/config/integral.hpp> |
| #include <boost/mpl/aux_/config/static_constant.hpp> |
| |
| #if !defined(BOOST_MPL_CFG_NO_NESTED_VALUE_ARITHMETIC_2) \ |
| && !defined(BOOST_MPL_PREPROCESSING_MODE) \ |
| && !defined(__CUDACC__) \ |
| && ( defined(BOOST_MSVC) \ |
| || BOOST_WORKAROUND(__EDG_VERSION__, <= 238) \ |
| ) |
| |
| # define BOOST_MPL_CFG_NO_NESTED_VALUE_ARITHMETIC_2 |
| |
| #endif |
| |
| namespace boost { namespace mpl { |
| |
| template< typename Tag > struct sign_impl; |
| |
| template< typename T > struct sign_tag |
| { |
| typedef typename T::tag type; |
| }; |
| |
| template< |
| typename BOOST_MPL_AUX_NA_PARAM(N) |
| > |
| struct sign |
| : sign_impl< |
| typename sign_tag<N>::type |
| >::template apply<N>::type |
| { |
| BOOST_MPL_AUX_LAMBDA_SUPPORT(1, sign, (N)) |
| }; |
| |
| BOOST_MPL_AUX_NA_SPEC(1, sign) |
| |
| template< |
| typename T |
| , T n1 |
| > |
| struct sign_c |
| : sign<integral_c<T,n1> > |
| { |
| }; |
| |
| #if defined(BOOST_MPL_CFG_NO_NESTED_VALUE_ARITHMETIC_2) |
| namespace aux { |
| template< typename T, T n > struct sign_wknd |
| { |
| BOOST_STATIC_CONSTANT(T, value = (n == 0 ? 0 : (n < 0 ? -1 : 1))); |
| typedef integral_c<T,value> type; |
| }; |
| } |
| #endif |
| |
| template<> |
| struct sign_impl<integral_c_tag> |
| { |
| #if defined(BOOST_MPL_CFG_NO_NESTED_VALUE_ARITHMETIC_2) |
| template< typename N > struct apply |
| : aux::sign_wknd< typename N::value_type, N::value > |
| #else |
| template< typename N > struct apply |
| : integral_c< typename N::value_type, (N::value == 0 ? 0 : (N::value < 0 ? -1 : 1)) > |
| #endif |
| { |
| }; |
| }; |
| |
| }} |
| |
| #endif // BOOST_MPL_SIGN_HPP_INCLUDED |