| // Copyright 2004 The Trustees of Indiana University. | |
| // Use, modification and distribution is subject to 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) | |
| // Authors: Douglas Gregor | |
| // Andrew Lumsdaine | |
| // | |
| // This file contains helps that enable concept-based overloading | |
| // within the Boost Graph Library. | |
| // | |
| #ifndef BOOST_GRAPH_OVERLOADING_HPP | |
| #define BOOST_GRAPH_OVERLOADING_HPP | |
| #include <boost/type_traits/is_base_and_derived.hpp> | |
| #include <boost/utility/enable_if.hpp> | |
| namespace boost { namespace graph { namespace detail { | |
| struct no_parameter {}; | |
| } } } // end namespace boost::graph::detail | |
| #ifndef BOOST_NO_SFINAE | |
| #define BOOST_GRAPH_ENABLE_IF_MODELS(Graph, Tag, Type) \ | |
| typename enable_if_c<(is_base_and_derived< \ | |
| Tag, \ | |
| typename graph_traits<Graph>::traversal_category>::value), \ | |
| Type>::type | |
| #define BOOST_GRAPH_ENABLE_IF_MODELS_PARM(Graph, Tag) \ | |
| , BOOST_GRAPH_ENABLE_IF_MODELS(Graph, Tag, \ | |
| ::boost::graph::detail::no_parameter) \ | |
| = ::boost::graph::detail::no_parameter() | |
| #else | |
| #define BOOST_GRAPH_ENABLE_IF_MODELS(Graph, Tag, Type) Type | |
| #define BOOST_GRAPH_ENABLE_IF_MODELS_PARM(Graph, Tag) | |
| #endif // no SFINAE support | |
| #endif // BOOST_GRAPH_OVERLOADING_HPP |