/*=============================================================================
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Copyright (c) 2007 Tobias Schwinger
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Distributed under the Boost Software License, Version 1.0. (See accompanying
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file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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==============================================================================*/
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#if !defined(BOOST_FUSION_REPETITIVE_VIEW_NEXT_IMPL_HPP_INCLUDED)
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#define BOOST_FUSION_REPETITIVE_VIEW_NEXT_IMPL_HPP_INCLUDED
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#include <boost/fusion/support/config.hpp>
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#include <boost/fusion/iterator/next.hpp>
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#include <boost/fusion/iterator/equal_to.hpp>
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namespace boost { namespace fusion
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{
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struct repetitive_view_iterator_tag;
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template <typename Sequence, typename Pos>
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struct repetitive_view_iterator;
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namespace extension
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{
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template <typename Tag>
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struct next_impl;
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template <>
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struct next_impl<repetitive_view_iterator_tag>
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{
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template<typename Iterator,
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bool Last = result_of::equal_to<typename Iterator::end_type,
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typename result_of::next<
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typename Iterator::pos_type
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>::type>::value >
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struct apply_nonempty // <Iterator,false>
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{
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// advanvce to next position
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typedef repetitive_view_iterator<
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typename Iterator::sequence_type,
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typename result_of::next<typename Iterator::pos_type>::type
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>
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type;
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BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
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static type call(Iterator const& i)
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{
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return type(i.seq, next(i.pos));
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}
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};
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template <typename Iterator>
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struct apply_nonempty<Iterator,true>
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{
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// reset to beginning
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typedef repetitive_view_iterator<
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typename Iterator::sequence_type,
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typename Iterator::first_type
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>
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type;
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BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
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static type call(Iterator const& i)
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{
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return type(i.seq);
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}
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};
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template <typename Iterator,
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bool Empty = result_of::equal_to<typename Iterator::end_type,
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typename Iterator::pos_type>::value >
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struct apply // <Iterator,false>
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: apply_nonempty<Iterator>
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{ };
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template <typename Iterator>
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struct apply<Iterator,true>
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{
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// eps^n = eps
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typedef Iterator type;
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BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
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static type call(Iterator const& i)
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{
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return type(i);
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}
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};
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};
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}
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}}
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#endif
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