boost/type_erasure/concept_interface.hpp
// 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_CONCEPT_INTERFACE_HPP_INCLUDED #define BOOST_TYPE_ERASURE_CONCEPT_INTERFACE_HPP_INCLUDED namespace boost { namespace type_erasure { /** * The @ref concept_interface class can be specialized to * add behavior to an @ref any. An @ref any inherits from * all the relevant specializations of @ref concept_interface. * * @ref concept_interface can be specialized for either * primitive or composite concepts. If a concept @c C1 * contains another concept @c C2, then the library guarantees * that the specialization of @ref concept_interface for * @c C2 is a base class of the specialization for @c C1. * This means that @c C1 can safely override members of @c C2. * * @ref concept_interface may only be specialized for user-defined * concepts. The library owns the specializations of its own * built in concepts. * * \tparam Concept The concept that we're specializing * @ref concept_interface for. One of its * placeholders should be @c ID. * \tparam Base The base of this class. Specializations of @ref * concept_interface must inherit publicly from this type. * \tparam ID The placeholder representing this type. * \tparam Enable A dummy parameter that can be used for SFINAE. * * The metafunctions @ref derived, @ref rebind_any, and @ref as_param * (which can be applied to @c Base) are useful for determining the * argument and return types of functions defined in @ref concept_interface. * * For dispatching the function use \call. */ template<class Concept, class Base, class ID, class Enable = void> struct concept_interface : Base {}; } } #endif