is_void.hpp 890 B

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  1. // (C) Copyright Steve Cleary, Beman Dawes, Howard Hinnant & John Maddock 2000.
  2. // Use, modification and distribution are subject to the Boost Software License,
  3. // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  4. // http://www.boost.org/LICENSE_1_0.txt).
  5. //
  6. // See http://www.boost.org/libs/type_traits for most recent version including documentation.
  7. #ifndef BOOST_TT_IS_VOID_HPP_INCLUDED
  8. #define BOOST_TT_IS_VOID_HPP_INCLUDED
  9. #include <boost/type_traits/integral_constant.hpp>
  10. namespace boost {
  11. template <class T>
  12. struct is_void : public false_type {};
  13. template<> struct is_void<void> : public true_type {};
  14. template<> struct is_void<const void> : public true_type{};
  15. template<> struct is_void<const volatile void> : public true_type{};
  16. template<> struct is_void<volatile void> : public true_type{};
  17. } // namespace boost
  18. #endif // BOOST_TT_IS_VOID_HPP_INCLUDED