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- // Boost.TypeErasure library
- //
- // Copyright 2011 Steven Watanabe
- //
- // 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)
- //
- // $Id$
- #ifndef BOOST_TYPE_ERASURE_REBIND_ANY_HPP_INCLUDED
- #define BOOST_TYPE_ERASURE_REBIND_ANY_HPP_INCLUDED
- #include <boost/mpl/if.hpp>
- #include <boost/type_traits/remove_cv.hpp>
- #include <boost/type_traits/remove_reference.hpp>
- #include <boost/type_erasure/is_placeholder.hpp>
- #include <boost/type_erasure/concept_of.hpp>
- namespace boost {
- namespace type_erasure {
- #ifndef BOOST_TYPE_ERASURE_DOXYGEN
- template<class Concept, class T>
- class any;
- #endif
- /**
- * A metafunction that changes the @ref placeholder of
- * an @ref any. If @c T is not a placeholder,
- * returns @c T unchanged. This class is intended
- * to be used in @ref concept_interface to deduce
- * the argument types from the arguments of the concept.
- *
- * @pre Any must be a specialization of @ref any or a base
- * class of such a specialization.
- *
- * \code
- * rebind_any<any<Concept>, _a>::type -> any<Concept, _a>
- * rebind_any<any<Concept>, _b&>::type -> any<Concept, _b&>
- * rebind_any<any<Concept>, _c&&>::type -> any<Concept, _c&&>
- * rebind_any<any<Concept>, int>::type -> int
- * \endcode
- *
- * @see derived, as_param
- */
- template<class Any, class T>
- struct rebind_any
- {
- #ifdef BOOST_TYPE_ERASURE_DOXYGEN
- typedef detail::unspecified type;
- #else
- typedef typename ::boost::mpl::if_<
- ::boost::type_erasure::is_placeholder<
- typename ::boost::remove_cv<
- typename ::boost::remove_reference<T>::type
- >::type
- >,
- ::boost::type_erasure::any<
- typename ::boost::type_erasure::concept_of<Any>::type,
- T
- >,
- T
- >::type type;
- #endif
- };
- #ifndef BOOST_NO_CXX11_TEMPLATE_ALIASES
- template<class Any, class T>
- using rebind_any_t = typename ::boost::type_erasure::rebind_any<Any, T>::type;
- #endif
- }
- }
- #endif
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