#ifndef BOOST_MPL_AUX_SINGLE_ELEMENT_ITER_HPP_INCLUDED | |
#define BOOST_MPL_AUX_SINGLE_ELEMENT_ITER_HPP_INCLUDED | |
// Copyright Aleksey Gurtovoy 2000-2004 | |
// | |
// 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) | |
// | |
// See http://www.boost.org/libs/mpl for documentation. | |
// $Id: single_element_iter.hpp 49267 2008-10-11 06:19:02Z agurtovoy $ | |
// $Date: 2008-10-11 02:19:02 -0400 (Sat, 11 Oct 2008) $ | |
// $Revision: 49267 $ | |
#include <boost/mpl/iterator_tags.hpp> | |
#include <boost/mpl/advance_fwd.hpp> | |
#include <boost/mpl/distance_fwd.hpp> | |
#include <boost/mpl/next_prior.hpp> | |
#include <boost/mpl/deref.hpp> | |
#include <boost/mpl/int.hpp> | |
#include <boost/mpl/aux_/nttp_decl.hpp> | |
#include <boost/mpl/aux_/value_wknd.hpp> | |
#include <boost/mpl/aux_/config/ctps.hpp> | |
namespace boost { namespace mpl { | |
#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION) | |
namespace aux { | |
template< typename T, BOOST_MPL_AUX_NTTP_DECL(int, is_last_) > | |
struct sel_iter; | |
template< typename T > | |
struct sel_iter<T,0> | |
{ | |
typedef random_access_iterator_tag category; | |
typedef sel_iter<T,1> next; | |
typedef T type; | |
}; | |
template< typename T > | |
struct sel_iter<T,1> | |
{ | |
typedef random_access_iterator_tag category; | |
typedef sel_iter<T,0> prior; | |
}; | |
} // namespace aux | |
template< typename T, BOOST_MPL_AUX_NTTP_DECL(int, is_last_), typename Distance > | |
struct advance< aux::sel_iter<T,is_last_>,Distance> | |
{ | |
typedef aux::sel_iter< | |
T | |
, ( is_last_ + BOOST_MPL_AUX_NESTED_VALUE_WKND(int, Distance) ) | |
> type; | |
}; | |
template< | |
typename T | |
, BOOST_MPL_AUX_NTTP_DECL(int, l1) | |
, BOOST_MPL_AUX_NTTP_DECL(int, l2) | |
> | |
struct distance< aux::sel_iter<T,l1>, aux::sel_iter<T,l2> > | |
: int_<( l2 - l1 )> | |
{ | |
}; | |
#else | |
namespace aux { | |
struct sel_iter_tag; | |
template< typename T, BOOST_MPL_AUX_NTTP_DECL(int, is_last_) > | |
struct sel_iter | |
{ | |
enum { pos_ = is_last_ }; | |
typedef aux::sel_iter_tag tag; | |
typedef random_access_iterator_tag category; | |
typedef sel_iter<T,(is_last_ + 1)> next; | |
typedef sel_iter<T,(is_last_ - 1)> prior; | |
typedef T type; | |
}; | |
} // namespace aux | |
template<> struct advance_impl<aux::sel_iter_tag> | |
{ | |
template< typename Iterator, typename N > struct apply | |
{ | |
enum { pos_ = Iterator::pos_, n_ = N::value }; | |
typedef aux::sel_iter< | |
typename Iterator::type | |
, (pos_ + n_) | |
> type; | |
}; | |
}; | |
template<> struct distance_impl<aux::sel_iter_tag> | |
{ | |
template< typename Iter1, typename Iter2 > struct apply | |
{ | |
enum { pos1_ = Iter1::pos_, pos2_ = Iter2::pos_ }; | |
typedef int_<( pos2_ - pos1_ )> type; | |
BOOST_STATIC_CONSTANT(int, value = ( pos2_ - pos1_ )); | |
}; | |
}; | |
#endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION | |
}} | |
#endif // BOOST_MPL_AUX_SINGLE_ELEMENT_ITER_HPP_INCLUDED |