projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 7c673cae FG |
1 | // Boost.TypeErasure library |
| 2 | // | |
| 3 | // Copyright 2011 Steven Watanabe | |
| 4 | // | |
| 5 | // Distributed under the Boost Software License Version 1.0. (See | |
| 6 | // accompanying file LICENSE_1_0.txt or copy at | |
| 7 | // http://www.boost.org/LICENSE_1_0.txt) | |
| 8 | // | |
| 9 | // $Id$ | |
| 10 | ||
| 11 | #ifndef BOOST_TYPE_ERASURE_PLACEHOLDER_OF_HPP_INCLUDED | |
| 12 | #define BOOST_TYPE_ERASURE_PLACEHOLDER_OF_HPP_INCLUDED | |
| 13 | ||
| 14 | namespace boost { | |
| 15 | namespace type_erasure { | |
| 16 | ||
| 17 | template<class Concept, class T> | |
| 18 | class any; | |
| 19 | ||
| 20 | template<class Concept, class T> | |
| 21 | class param; | |
| 22 | ||
| 23 | /** | |
| 24 | * A metafunction returning the (const/reference qualified) placeholder | |
| 25 | * corresponding to an @ref any. It will also work for all bases | |
| 26 | * of @ref any, so it can be applied to the @c Base | |
| 27 | * parameter of @ref concept_interface. | |
| 28 | */ | |
| 29 | template<class T> | |
| 30 | struct placeholder_of | |
| 31 | { | |
| 32 | #ifdef BOOST_TYPE_ERASURE_DOXYGEN | |
| 33 | typedef detail::unspecified type; | |
| 34 | #else | |
| 35 | typedef typename ::boost::type_erasure::placeholder_of< | |
| 36 | typename T::_boost_type_erasure_derived_type | |
| 37 | >::type type; | |
| 38 | #endif | |
| 39 | }; | |
| 40 | ||
| 41 | /** INTERNAL ONLY */ | |
| 42 | template<class Concept, class T> | |
| 43 | struct placeholder_of< ::boost::type_erasure::any<Concept, T> > | |
| 44 | { | |
| 45 | typedef T type; | |
| 46 | }; | |
| 47 | ||
| 48 | /** INTERNAL ONLY */ | |
| 49 | template<class Concept, class T> | |
| 50 | struct placeholder_of< ::boost::type_erasure::param<Concept, T> > | |
| 51 | { | |
| 52 | typedef T type; | |
| 53 | }; | |
| 54 | ||
| 55 | } | |
| 56 | } | |
| 57 | ||
| 58 | #endif |