ceph/src/boost/boost/type_traits/conjunction.hpp

   1 /*
   2 Copyright 2020 Glen Joseph Fernandes
   3 (glenjofe@gmail.com)
   4
   5 Distributed under the Boost Software License,
   6 Version 1.0. (See accompanying file LICENSE_1_0.txt
   7 or copy at http://www.boost.org/LICENSE_1_0.txt)
   8 */
   9
  10 #ifndef BOOST_TT_CONJUNCTION_HPP_INCLUDED
  11 #define BOOST_TT_CONJUNCTION_HPP_INCLUDED
  12
  13 #include <boost/type_traits/conditional.hpp>
  14 #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
  15 #include <boost/type_traits/integral_constant.hpp>
  16 #endif
  17
  18 namespace boost {
  19
  20 #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
  21 template<class...>
  22 struct conjunction
  23     : true_type { };
  24
  25 template<class T>
  26 struct conjunction<T>
  27     : T { };
  28
  29 template<class T, class... U>
  30 struct conjunction<T, U...>
  31     : conditional<bool(T::value), conjunction<U...>, T>::type { };
  32 #else
  33 template<class T, class U>
  34 struct conjunction
  35     : conditional<bool(T::value), U, T>::type { };
  36 #endif
  37
  38 } /* boost */
  39
  40 #endif