Chris@16: 
Chris@16: #ifndef BOOST_MPL_UNIQUE_HPP_INCLUDED
Chris@16: #define BOOST_MPL_UNIQUE_HPP_INCLUDED
Chris@16: 
Chris@16: // Copyright Aleksey Gurtovoy 2000-2004
Chris@16: // Copyright John R. Bandela 2000-2002
Chris@16: //
Chris@16: // Distributed under the Boost Software License, Version 1.0. 
Chris@16: // (See accompanying file LICENSE_1_0.txt or copy at 
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //
Chris@16: // See http://www.boost.org/libs/mpl for documentation.
Chris@16: 
Chris@101: // $Id$
Chris@101: // $Date$
Chris@101: // $Revision$
Chris@16: 
Chris@16: #include <boost/mpl/fold.hpp>
Chris@16: #include <boost/mpl/reverse_fold.hpp>
Chris@16: #include <boost/mpl/eval_if.hpp>
Chris@16: #include <boost/mpl/and.hpp>
Chris@16: #include <boost/mpl/identity.hpp>
Chris@16: #include <boost/mpl/pair.hpp>
Chris@16: #include <boost/mpl/apply.hpp>
Chris@16: #include <boost/mpl/aux_/inserter_algorithm.hpp>
Chris@16: #include <boost/mpl/aux_/na.hpp>
Chris@16: #include <boost/mpl/aux_/na_spec.hpp>
Chris@16: #include <boost/mpl/aux_/lambda_spec.hpp>
Chris@16: 
Chris@16: namespace boost { namespace mpl {
Chris@16: 
Chris@16: namespace aux {
Chris@16: 
Chris@16: template< typename Predicate, typename Operation >
Chris@16: struct unique_op
Chris@16: {
Chris@16:     template< typename Pair, typename T > struct apply
Chris@16:     {
Chris@16:         typedef typename Pair::first seq_;
Chris@16:         typedef typename Pair::second prior_;
Chris@16:         typedef typename eval_if<
Chris@16:               and_< is_not_na<prior_>, apply2<Predicate,prior_,T> >
Chris@16:             , identity<seq_>
Chris@16:             , apply2<Operation,seq_,T>
Chris@16:             >::type new_seq_;
Chris@16: 
Chris@16:         typedef pair<new_seq_,T> type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: template<
Chris@16:       typename Sequence
Chris@16:     , typename Predicate
Chris@16:     , typename Inserter
Chris@16:     >
Chris@16: struct unique_impl
Chris@16:     : first< typename fold<
Chris@16:           Sequence
Chris@16:         , pair< typename Inserter::state,na >
Chris@16:         , protect< aux::unique_op<Predicate,typename Inserter::operation> >
Chris@16:         >::type >
Chris@16: {
Chris@16: };
Chris@16: 
Chris@16: template<
Chris@16:       typename Sequence
Chris@16:     , typename Predicate
Chris@16:     , typename Inserter
Chris@16:     >
Chris@16: struct reverse_unique_impl
Chris@16:     : first< typename reverse_fold<
Chris@16:           Sequence
Chris@16:         , pair< typename Inserter::state,na >
Chris@16:         , protect< aux::unique_op<Predicate,typename Inserter::operation> >
Chris@16:         >::type >
Chris@16: {
Chris@16: };
Chris@16: 
Chris@16: } // namespace aux
Chris@16: 
Chris@16: BOOST_MPL_AUX_INSERTER_ALGORITHM_DEF(3, unique)
Chris@16: 
Chris@16: }}
Chris@16: 
Chris@16: #endif // BOOST_MPL_UNIQUE_HPP_INCLUDED