map/aux_/iterator.hpp

0001
0002 #ifndef BOOST_MPL_MAP_AUX_ITERATOR_HPP_INCLUDED
0003 #define BOOST_MPL_MAP_AUX_ITERATOR_HPP_INCLUDED
0004
0005 // Copyright Aleksey Gurtovoy 2003-2004
0006 // Copyright David Abrahams 2003-2004
0007 //
0008 // Distributed under the Boost Software License, Version 1.0.
0009 // (See accompanying file LICENSE_1_0.txt or copy at
0010 // http://www.boost.org/LICENSE_1_0.txt)
0011 //
0012 // See http://www.boost.org/libs/mpl for documentation.
0013
0014 // $Id$
0015 // $Date$
0016 // $Revision$
0017
0018 #include <boost/mpl/map/aux_/map0.hpp>
0019 #include <boost/mpl/map/aux_/at_impl.hpp>
0020 #include <boost/mpl/map/aux_/tag.hpp>
0021 #include <boost/mpl/iterator_tags.hpp>
0022 #include <boost/mpl/if.hpp>
0023 #include <boost/mpl/next.hpp>
0024 #include <boost/mpl/deref.hpp>
0025 #include <boost/mpl/long.hpp>
0026 #include <boost/mpl/void.hpp>
0027 #include <boost/mpl/aux_/nttp_decl.hpp>
0028 #include <boost/mpl/aux_/config/ctps.hpp>
0029
0030 namespace boost { namespace mpl {
0031
0032 #if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
0033
0034 template<
0035       typename Map
0036     , long order
0037     , long max_order
0038     >
0039 struct next_order
0040     : if_<
0041           is_void_< typename item_by_order<Map,order>::type >
0042         , next_order<Map,(order+1),max_order>
0043         , long_<order>
0044         >::type
0045 {
0046 };
0047
0048 template<
0049       typename Map
0050     , long max_order
0051     >
0052 struct next_order<Map,max_order,max_order>
0053     : long_<max_order>
0054 {
0055 };
0056
0057
0058 template< typename Map, long order, long max_order >
0059 struct m_iter
0060 {
0061     typedef forward_iterator_tag category;
0062     typedef typename item_by_order<Map,order>::type type;
0063 };
0064
0065 template< typename Map, long max_order >
0066 struct m_iter<Map,max_order,max_order>
0067 {
0068     typedef forward_iterator_tag category;
0069 };
0070
0071
0072 template< typename Map, long order, long max_order >
0073 struct next< m_iter<Map,order,max_order> >
0074 {
0075     typedef m_iter<
0076           Map
0077         , next_order<Map,order+1,max_order>::value
0078         , max_order
0079         > type;
0080 };
0081
0082 template< typename Map, long max_order >
0083 struct next< m_iter<Map,max_order,max_order> >
0084 {
0085 };
0086
0087 #else
0088
0089 template<
0090       typename Map
0091     , BOOST_MPL_AUX_NTTP_DECL(long, order)
0092     , BOOST_MPL_AUX_NTTP_DECL(long, max_order)
0093     >
0094 struct next_order;
0095
0096 template<
0097       typename Map
0098     , BOOST_MPL_AUX_NTTP_DECL(long, order)
0099     , BOOST_MPL_AUX_NTTP_DECL(long, max_order)
0100     >
0101 struct next_order_impl
0102     : if_<
0103           is_void_< typename item_by_order<Map,order>::type >
0104         , next_order<Map,(order+1),max_order>
0105         , long_<order>
0106         >::type
0107     {
0108     };
0109
0110 template<
0111       typename Map
0112     , BOOST_MPL_AUX_NTTP_DECL(long, order)
0113     , BOOST_MPL_AUX_NTTP_DECL(long, max_order)
0114     >
0115 struct next_order
0116     : if_c<
0117           (order != max_order)
0118         , next_order_impl<Map,order,max_order>
0119         , long_<order>
0120         >::type
0121 {
0122 };
0123
0124
0125 template<
0126       typename Map
0127     , BOOST_MPL_AUX_NTTP_DECL(long, order)
0128     , BOOST_MPL_AUX_NTTP_DECL(long, max_order)
0129     >
0130 struct m_iter;
0131
0132 struct m_iter_empty_base {};
0133
0134 template<
0135       typename Map
0136     , BOOST_MPL_AUX_NTTP_DECL(long, order)
0137     , BOOST_MPL_AUX_NTTP_DECL(long, max_order)
0138     >
0139 struct m_iter_base
0140 {
0141     typedef typename item_by_order<Map,order>::type type;
0142
0143     typedef m_iter<
0144           Map
0145         , next_order<Map,order+1,max_order>::value
0146         , max_order
0147         > next;
0148 };
0149
0150 template<
0151       typename Map
0152     , BOOST_MPL_AUX_NTTP_DECL(long, order)
0153     , BOOST_MPL_AUX_NTTP_DECL(long, max_order)
0154     >
0155 struct m_iter
0156   : if_c<
0157           (order == max_order)
0158         , m_iter_empty_base
0159         , m_iter_base<Map,order,max_order>
0160         >::type
0161 {
0162     typedef forward_iterator_tag category;
0163 };
0164
0165 #endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
0166
0167 }}
0168
0169 #endif // BOOST_MPL_MAP_AUX_ITERATOR_HPP_INCLUDED