MySources/boost_graph/boost/graph/overloading.hpp

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// 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