47 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			47 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| // Copyright 2004 The Trustees of Indiana University.
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| 
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| // Use, modification and distribution is subject to the Boost Software
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| // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
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| // http://www.boost.org/LICENSE_1_0.txt)
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| 
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| //  Authors: Douglas Gregor
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| //           Andrew Lumsdaine
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| 
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| //
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| // This file contains helps that enable concept-based overloading
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| // within the Boost Graph Library.
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| //
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| #ifndef BOOST_GRAPH_OVERLOADING_HPP
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| #define BOOST_GRAPH_OVERLOADING_HPP
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| 
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| #include <boost/type_traits/is_base_and_derived.hpp>
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| #include <boost/utility/enable_if.hpp>
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| 
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| namespace boost {  namespace graph { namespace detail {
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| 
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| struct no_parameter {};
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| 
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| } } } // end namespace boost::graph::detail
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| 
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| #ifndef BOOST_NO_SFINAE
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| 
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| #define BOOST_GRAPH_ENABLE_IF_MODELS(Graph, Tag, Type)               \
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|   typename enable_if_c<(is_base_and_derived<                         \
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|                           Tag,                                       \
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|                           typename graph_traits<Graph>::traversal_category>::value), \
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|                        Type>::type
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| 
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| #define BOOST_GRAPH_ENABLE_IF_MODELS_PARM(Graph, Tag)                   \
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|   , BOOST_GRAPH_ENABLE_IF_MODELS(Graph, Tag,                            \
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|                                  ::boost::graph::detail::no_parameter)  \
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|     = ::boost::graph::detail::no_parameter()
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| 
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| #else
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| 
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| #define BOOST_GRAPH_ENABLE_IF_MODELS(Graph, Tag, Type) Type
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| #define BOOST_GRAPH_ENABLE_IF_MODELS_PARM(Graph, Tag)
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| 
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| #endif // no SFINAE support
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| 
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| #endif // BOOST_GRAPH_OVERLOADING_HPP
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