boost/mpl/advance.hpp
//-----------------------------------------------------------------------------
// boost mpl/advance.hpp header file
// See http://www.boost.org for updates, documentation, and revision history.
//-----------------------------------------------------------------------------
//
// Copyright (c) 2000-02
// Aleksey Gurtovoy
//
// Permission to use, copy, modify, distribute and sell this software
// and its documentation for any purpose is hereby granted without fee,
// provided that the above copyright notice appears in all copies and
// that both the copyright notice and this permission notice appear in
// supporting documentation. No representations are made about the
// suitability of this software for any purpose. It is provided "as is"
// without express or implied warranty.
#ifndef BOOST_MPL_ADVANCE_HPP_INCLUDED
#define BOOST_MPL_ADVANCE_HPP_INCLUDED
#include "boost/mpl/negate.hpp"
#include "boost/mpl/less.hpp"
#include "boost/mpl/integral_c.hpp"
#include "boost/mpl/if.hpp"
#include "boost/mpl/iterator_tag.hpp"
#include "boost/mpl/aux_/advance_forward.hpp"
#include "boost/mpl/aux_/advance_backward.hpp"
#include "boost/mpl/aux_/iterator_category.hpp"
#include "boost/mpl/aux_/iterator_names.hpp"
#include "boost/mpl/aux_/msvc_never_true.hpp"
#include "boost/mpl/aux_/common_name_wknd.hpp"
#include "boost/mpl/aux_/apply.hpp"
#include "boost/mpl/aux_/void_spec.hpp"
#include "boost/mpl/aux_/config/nttp.hpp"
#include "boost/config.hpp"
namespace boost {
namespace mpl {
BOOST_MPL_AUX_COMMON_NAME_WKND(advance)
#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
namespace aux {
// forward/bidirectional iterators
template< typename Category, typename Iterator, typename N >
struct advance_impl
{
typedef typename less< N,integral_c<long,0> >::type backward_;
typedef typename if_< backward_, negate<N>, N >::type offset_;
typedef typename if_<
backward_
, aux::advance_backward< BOOST_MPL_AUX_VALUE_WKND(offset_)::value >
, aux::advance_forward< BOOST_MPL_AUX_VALUE_WKND(offset_)::value >
>::type algo_;
typedef typename BOOST_MPL_AUX_APPLY1(algo_,Iterator)::type type;
};
// random-access iterators
template< typename Iterator, typename N >
struct advance_impl<ra_iter_tag_,Iterator,N>
{
typedef typename Iterator
::template BOOST_MPL_AUX_ITERATOR_ADVANCE<N>::type type;
};
} // namespace aux
BOOST_MPL_AUX_AGLORITHM_NAMESPACE_BEGIN
template<
typename BOOST_MPL_AUX_VOID_SPEC_PARAM(Iterator)
, typename BOOST_MPL_AUX_VOID_SPEC_PARAM(N)
>
struct advance
{
typedef typename aux::advance_impl<
typename BOOST_MPL_AUX_ITERATOR_CATEGORY(Iterator)
, Iterator
, N
>::type type;
};
BOOST_MPL_AUX_AGLORITHM_NAMESPACE_END
template<
typename Iterator
, BOOST_MPL_AUX_NTTP_DECL(long, N)
>
struct advance_c
{
typedef typename aux::advance_impl<
typename BOOST_MPL_AUX_ITERATOR_CATEGORY(Iterator)
, Iterator
, integral_c<long,N>
>::type type;
};
#else // no partial specialization
namespace aux {
// forward/bidirectional iterators
template< typename Category >
struct advance_impl
{
template< typename Iterator, typename N > struct result_
{
enum { n = N::value }; // MSVC 7.x workaround
typedef typename if_c<
(n < 0)
, aux::advance_backward<(-n)>
, aux::advance_forward<n>
>::type algo_;
typedef typename BOOST_MPL_AUX_APPLY1(algo_,Iterator)::type type;
};
};
// random-access iterators
#if defined(BOOST_MSVC) && BOOST_MSVC < 1300
// msvc_advance
#define BOOST_MPL_AUX_MSVC_DTW_NAME msvc_advance
#define BOOST_MPL_AUX_MSVC_DTW_ORIGINAL_NAME BOOST_MPL_AUX_ITERATOR_ADVANCE
#define BOOST_MPL_AUX_MSVC_DTW_ARITY 1
#include "boost/mpl/aux_/msvc_dtw.hpp"
template<>
struct advance_impl<ra_iter_tag_>
{
template< typename Iterator, typename N > struct result_
{
typedef typename msvc_advance<Iterator>
::template result_<N>::type type;
};
};
#else
template<>
struct advance_impl<ra_iter_tag_>
{
template< typename Iterator, typename N > struct result_
{
typedef typename Iterator
::template BOOST_MPL_AUX_ITERATOR_ADVANCE<N>::type type;
};
};
#endif
} // namespace aux
BOOST_MPL_AUX_AGLORITHM_NAMESPACE_BEGIN
template<
typename BOOST_MPL_AUX_VOID_SPEC_PARAM(Iterator)
, typename BOOST_MPL_AUX_VOID_SPEC_PARAM(N)
>
struct advance
{
typedef typename BOOST_MPL_AUX_ITERATOR_CATEGORY(Iterator) tag_;
typedef typename aux::advance_impl<tag_>
::template result_<
Iterator
, N
>::type type;
};
BOOST_MPL_AUX_AGLORITHM_NAMESPACE_END
template<
typename Iterator
, BOOST_MPL_AUX_NTTP_DECL(long, N)
>
struct advance_c
{
typedef typename BOOST_MPL_AUX_ITERATOR_CATEGORY(Iterator) tag_;
typedef typename aux::advance_impl<tag_>
::template result_<
Iterator
, integral_c<long,N>
>::type type;
};
#endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
BOOST_MPL_AUX_ALGORITHM_VOID_SPEC(2, advance)
} // namespace mpl
} // namespace boost
#endif // BOOST_MPL_ADVANCE_HPP_INCLUDED