1 /*============================================================================= 2 Copyright (c) 2001-2011 Joel de Guzman 3 Copyright (c) 2006 Dan Marsden 4 5 Distributed under the Boost Software License, Version 1.0. (See accompanying 6 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) 7 ==============================================================================*/ 8 #if !defined(BOOST_FUSION_DEREF_IMPL_20060222_1952) 9 #define BOOST_FUSION_DEREF_IMPL_20060222_1952 10 11 #include <boost/static_assert.hpp> 12 #include <boost/type_traits/is_const.hpp> 13 #include <boost/mpl/if.hpp> 14 15 #include <string> 16 17 namespace example 18 { 19 struct example_struct_iterator_tag; 20 21 template<typename Struct, int Pos> 22 struct example_struct_iterator; 23 } 24 25 namespace boost { namespace fusion { 26 27 namespace extension 28 { 29 template<typename Tag> 30 struct deref_impl; 31 32 template<> 33 struct deref_impl<example::example_struct_iterator_tag> 34 { 35 template<typename Iterator> 36 struct apply; 37 38 template<typename Struct> 39 struct apply<example::example_struct_iterator<Struct, 0> > 40 { 41 typedef typename mpl::if_< 42 is_const<Struct>, std::string const&, std::string&>::type type; 43 44 static type callboost::fusion::extension::deref_impl::apply45 call(example::example_struct_iterator<Struct, 0> const& it) 46 { 47 return it.struct_.name; 48 } 49 }; 50 51 template<typename Struct> 52 struct apply<example::example_struct_iterator<Struct, 1> > 53 { 54 typedef typename mpl::if_< 55 is_const<Struct>, int const&, int&>::type type; 56 57 static type callboost::fusion::extension::deref_impl::apply58 call(example::example_struct_iterator<Struct, 1> const& it) 59 { 60 return it.struct_.age; 61 } 62 }; 63 }; 64 } 65 }} 66 67 #endif 68