53 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
		
		
			
		
	
	
			53 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
|   | /*============================================================================= | ||
|  |     Copyright (c) 2001-2011 Joel de Guzman | ||
|  | 
 | ||
|  |     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) | ||
|  | ==============================================================================*/ | ||
|  | #if !defined(BOOST_FUSION_AT_IMPL_09262006_1920) | ||
|  | #define BOOST_FUSION_AT_IMPL_09262006_1920 | ||
|  | 
 | ||
|  | #include <boost/fusion/support/config.hpp> | ||
|  | #include <boost/tuple/tuple.hpp> | ||
|  | #include <boost/mpl/if.hpp> | ||
|  | 
 | ||
|  | namespace boost { namespace fusion  | ||
|  | { | ||
|  |     struct boost_tuple_tag; | ||
|  | 
 | ||
|  |     namespace extension | ||
|  |     { | ||
|  |         template<typename T> | ||
|  |         struct at_impl; | ||
|  | 
 | ||
|  |         template <> | ||
|  |         struct at_impl<boost_tuple_tag> | ||
|  |         { | ||
|  |             template <typename Sequence, typename N> | ||
|  |             struct apply  | ||
|  |             { | ||
|  |                 typedef typename | ||
|  |                     tuples::element<N::value, Sequence>::type  | ||
|  |                 element; | ||
|  |      | ||
|  |                 typedef typename  | ||
|  |                     mpl::if_< | ||
|  |                         is_const<Sequence> | ||
|  |                       , typename tuples::access_traits<element>::const_type | ||
|  |                       , typename tuples::access_traits<element>::non_const_type | ||
|  |                     >::type  | ||
|  |                 type; | ||
|  |      | ||
|  |                 BOOST_FUSION_GPU_ENABLED | ||
|  |                 static type | ||
|  |                 call(Sequence& seq) | ||
|  |                 { | ||
|  |                     return tuples::get<N::value>(seq); | ||
|  |                 } | ||
|  |             }; | ||
|  |         }; | ||
|  |     } | ||
|  | }} | ||
|  | 
 | ||
|  | #endif |