| /////////////////////////////////////////////////////////////////////////////// |
| /// \file is_noncopyable.hpp |
| /// Utility for detecting when types are non-copyable |
| // |
| // Copyright 2008 Eric Niebler. 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) |
| |
| #ifndef BOOST_PROTO_DETAIL_IS_NONCOPYABLE_HPP_EAN_19_07_2012 |
| #define BOOST_PROTO_DETAIL_IS_NONCOPYABLE_HPP_EAN_19_07_2012 |
| |
| #include <boost/noncopyable.hpp> |
| #include <boost/mpl/or.hpp> |
| #include <boost/mpl/bool.hpp> |
| #include <boost/type_traits/is_base_of.hpp> |
| #include <boost/type_traits/is_abstract.hpp> |
| #include <boost/type_traits/is_function.hpp> |
| #include <boost/proto/proto_fwd.hpp> |
| |
| namespace boost { namespace proto { namespace detail |
| { |
| // All classes derived from std::ios_base have these public nested types, |
| // and are non-copyable. This is an imperfect test, but it's the best we |
| // we can do. |
| template<typename T> |
| yes_type check_is_iostream( |
| typename T::failure * |
| , typename T::Init * |
| , typename T::fmtflags * |
| , typename T::iostate * |
| , typename T::openmode * |
| , typename T::seekdir * |
| ); |
| |
| template<typename T> |
| no_type check_is_iostream(...); |
| |
| template<typename T> |
| struct is_iostream |
| { |
| static bool const value = sizeof(yes_type) == sizeof(check_is_iostream<T>(0,0,0,0,0,0)); |
| typedef mpl::bool_<value> type; |
| }; |
| |
| /// INTERNAL ONLY |
| // This should be a customization point. And it serves the same purpose |
| // as the is_noncopyable trait in Boost.Foreach. |
| template<typename T> |
| struct is_noncopyable |
| : mpl::or_< |
| is_function<T> |
| , is_abstract<T> |
| , is_iostream<T> |
| , is_base_of<noncopyable, T> |
| > |
| {}; |
| |
| template<typename T, std::size_t N> |
| struct is_noncopyable<T[N]> |
| : mpl::true_ |
| {}; |
| |
| }}} |
| |
| #endif |