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- ///////////////////////////////////////////////////////////////////////////////
- /// \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
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