1 // (C) Copyright John Maddock & Thorsten Ottosen 2005. 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 8 9 #ifndef BOOST_TT_DECAY_HPP_INCLUDED 10 #define BOOST_TT_DECAY_HPP_INCLUDED 11 12 #include <boost/type_traits/is_array.hpp> 13 #include <boost/type_traits/is_function.hpp> 14 #include <boost/type_traits/remove_bounds.hpp> 15 #include <boost/type_traits/add_pointer.hpp> 16 #include <boost/type_traits/remove_reference.hpp> 17 #include <boost/type_traits/remove_cv.hpp> 18 19 namespace boost 20 { 21 22 namespace detail 23 { 24 25 template <class T, bool Array, bool Function> struct decay_imp { typedef typename remove_cv<T>::type type; }; 26 template <class T> struct decay_imp<T, true, false> { typedef typename remove_bounds<T>::type* type; }; 27 template <class T> struct decay_imp<T, false, true> { typedef T* type; }; 28 29 } 30 31 template< class T > 32 struct decay 33 { 34 private: 35 typedef typename remove_reference<T>::type Ty; 36 public: 37 typedef typename boost::detail::decay_imp<Ty, boost::is_array<Ty>::value, boost::is_function<Ty>::value>::type type; 38 }; 39 40 #if !defined(BOOST_NO_CXX11_TEMPLATE_ALIASES) 41 42 template <class T> using decay_t = typename decay<T>::type; 43 44 #endif 45 46 } // namespace boost 47 48 49 #endif // BOOST_TT_DECAY_HPP_INCLUDED 50