forked from boostorg/mpl
50 lines
1.5 KiB
C++
50 lines
1.5 KiB
C++
//-----------------------------------------------------------------------------
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// boost mpl/aux_/back_impl.hpp header file
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// See http://www.boost.org for updates, documentation, and revision history.
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//-----------------------------------------------------------------------------
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//
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// Copyright (c) 2000-02
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// Aleksey Gurtovoy
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//
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// Distributed under the Boost Software License, Version 1.0. (See
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// accompanying file LICENSE_1_0.txt or copy at
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// http://www.boost.org/LICENSE_1_0.txt)
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#ifndef BOOST_MPL_AUX_BACK_IMPL_HPP_INCLUDED
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#define BOOST_MPL_AUX_BACK_IMPL_HPP_INCLUDED
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#include "boost/mpl/begin_end.hpp"
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#include "boost/mpl/prior.hpp"
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#include "boost/mpl/aux_/deref_wknd.hpp"
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#include "boost/mpl/aux_/traits_lambda_spec.hpp"
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#include "boost/mpl/aux_/config/eti.hpp"
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namespace boost {
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namespace mpl {
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// default implementation, requires at least bi-directional iterators;
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// conrete sequences might override it by specializing either the
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// 'back_traits' or the primary 'back' template
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template< typename Tag >
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struct back_traits
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{
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template< typename Sequence > struct algorithm
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{
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typedef typename end<Sequence>::type iter_;
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#if defined(BOOST_MPL_MSVC_ETI_BUG)
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typedef typename prior<iter_>::type last_;
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#else
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typedef typename iter_::prior last_;
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#endif
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typedef typename BOOST_MPL_AUX_DEREF_WNKD(last_) type;
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};
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};
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BOOST_MPL_ALGORITM_TRAITS_LAMBDA_SPEC(1,back_traits)
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} // namespace mpl
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} // namespace boost
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#endif // BOOST_MPL_AUX_BACK_IMPL_HPP_INCLUDED
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