72 lines
2.2 KiB
C++
72 lines
2.2 KiB
C++
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#ifndef BOOST_MPL_AUX_PUSH_FRONT_IMPL_HPP_INCLUDED
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#define BOOST_MPL_AUX_PUSH_FRONT_IMPL_HPP_INCLUDED
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// Copyright Aleksey Gurtovoy 2000-2008
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//
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// Distributed under the Boost Software License, Version 1.0.
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// (See 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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//
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// See http://www.boost.org/libs/mpl for documentation.
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// $Id: push_front_impl.hpp 55679 2009-08-20 07:50:16Z agurtovoy $
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// $Date: 2009-08-20 03:50:16 -0400 (Thu, 20 Aug 2009) $
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// $Revision: 55679 $
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#include <boost/mpl/push_front_fwd.hpp>
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#include <boost/mpl/assert.hpp>
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#include <boost/mpl/aux_/has_type.hpp>
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#include <boost/mpl/aux_/traits_lambda_spec.hpp>
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#include <boost/mpl/aux_/config/forwarding.hpp>
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#include <boost/mpl/aux_/config/static_constant.hpp>
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#include <boost/type_traits/is_same.hpp>
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namespace boost { namespace mpl {
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struct has_push_front_arg {};
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// agurt 05/feb/04: no default implementation; the stub definition is needed
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// to enable the default 'has_push_front' implementation below
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template< typename Tag >
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struct push_front_impl
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{
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template< typename Sequence, typename T > struct apply
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{
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// should be instantiated only in the context of 'has_push_front_impl';
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// if you've got an assert here, you are requesting a 'push_front'
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// specialization that doesn't exist.
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BOOST_MPL_ASSERT_MSG(
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( boost::is_same< T, has_push_front_arg >::value )
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, REQUESTED_PUSH_FRONT_SPECIALIZATION_FOR_SEQUENCE_DOES_NOT_EXIST
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, ( Sequence )
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);
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};
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};
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template< typename Tag >
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struct has_push_front_impl
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{
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template< typename Seq > struct apply
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#if !defined(BOOST_MPL_CFG_NO_NESTED_FORWARDING)
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: aux::has_type< push_front< Seq, has_push_front_arg > >
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{
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#else
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{
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typedef aux::has_type< push_front< Seq, has_push_front_arg > > type;
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BOOST_STATIC_CONSTANT(bool, value =
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(aux::has_type< push_front< Seq, has_push_front_arg > >::value)
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);
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#endif
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};
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};
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BOOST_MPL_ALGORITM_TRAITS_LAMBDA_SPEC(2, push_front_impl)
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BOOST_MPL_ALGORITM_TRAITS_LAMBDA_SPEC(1, has_push_front_impl)
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}}
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#endif // BOOST_MPL_AUX_PUSH_FRONT_IMPL_HPP_INCLUDED
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