boost/mpl/transform.hpp

0001
0002 #ifndef BOOST_MPL_TRANSFORM_HPP_INCLUDED
0003 #define BOOST_MPL_TRANSFORM_HPP_INCLUDED
0004
0005 // Copyright Aleksey Gurtovoy 2000-2004
0006 // Copyright David Abrahams 2003-2004
0007 //
0008 // Distributed under the Boost Software License, Version 1.0.
0009 // (See accompanying file LICENSE_1_0.txt or copy at
0010 // http://www.boost.org/LICENSE_1_0.txt)
0011 //
0012 // See http://www.boost.org/libs/mpl for documentation.
0013
0014 // $Id$
0015 // $Date$
0016 // $Revision$
0017
0018 #include <boost/mpl/fold.hpp>
0019 #include <boost/mpl/reverse_fold.hpp>
0020 #include <boost/mpl/pair_view.hpp>
0021 #include <boost/mpl/is_sequence.hpp>
0022 #include <boost/mpl/eval_if.hpp>
0023 #include <boost/mpl/lambda.hpp>
0024 #include <boost/mpl/bind.hpp>
0025 #include <boost/mpl/or.hpp>
0026 #include <boost/mpl/not.hpp>
0027 #include <boost/mpl/aux_/na.hpp>
0028 #include <boost/mpl/aux_/inserter_algorithm.hpp>
0029
0030 namespace boost { namespace mpl {
0031
0032 namespace aux {
0033
0034 template<
0035       typename Seq
0036     , typename Op
0037     , typename In
0038     >
0039 struct transform1_impl
0040     : fold<
0041           Seq
0042         , typename In::state
0043         , bind2< typename lambda< typename In::operation >::type
0044             , _1
0045             , bind1< typename lambda<Op>::type, _2>
0046             >
0047         >
0048 {
0049 };
0050
0051 template<
0052       typename Seq
0053     , typename Op
0054     , typename In
0055     >
0056 struct reverse_transform1_impl
0057     : reverse_fold<
0058           Seq
0059         , typename In::state
0060         , bind2< typename lambda< typename In::operation >::type
0061             , _1
0062             , bind1< typename lambda<Op>::type, _2>
0063             >
0064         >
0065 {
0066 };
0067
0068 template<
0069       typename Seq1
0070     , typename Seq2
0071     , typename Op
0072     , typename In
0073     >
0074 struct transform2_impl
0075     : fold<
0076           pair_view<Seq1,Seq2>
0077         , typename In::state
0078         , bind2< typename lambda< typename In::operation >::type
0079             , _1
0080             , bind2<
0081                   typename lambda<Op>::type
0082                 , bind1<first<>,_2>
0083                 , bind1<second<>,_2>
0084                 >
0085             >
0086         >
0087 {
0088 };
0089
0090 template<
0091       typename Seq1
0092     , typename Seq2
0093     , typename Op
0094     , typename In
0095     >
0096 struct reverse_transform2_impl
0097     : reverse_fold<
0098           pair_view<Seq1,Seq2>
0099         , typename In::state
0100         , bind2< typename lambda< typename In::operation >::type
0101             , _1
0102             , bind2< typename lambda< Op >::type
0103                 , bind1<first<>,_2>
0104                 , bind1<second<>,_2>
0105                 >
0106             >
0107         >
0108 {
0109 };
0110
0111 } // namespace aux
0112
0113 BOOST_MPL_AUX_INSERTER_ALGORITHM_DEF(3, transform1)
0114 BOOST_MPL_AUX_INSERTER_ALGORITHM_DEF(4, transform2)
0115
0116 #define AUX778076_TRANSFORM_DEF(name)                                   \
0117 template<                                                               \
0118       typename BOOST_MPL_AUX_NA_PARAM(Seq1)                             \
0119     , typename BOOST_MPL_AUX_NA_PARAM(Seq2OrOperation)                  \
0120     , typename BOOST_MPL_AUX_NA_PARAM(OperationOrInserter)              \
0121     , typename BOOST_MPL_AUX_NA_PARAM(Inserter)                         \
0122     >                                                                   \
0123 struct name                                                             \
0124 {                                                                       \
0125     typedef typename eval_if<                                           \
0126           or_<                                                          \
0127               is_na<OperationOrInserter>                                \
0128             , is_lambda_expression< Seq2OrOperation >                   \
0129             , not_< is_sequence<Seq2OrOperation> >                      \
0130             >                                                           \
0131         , name##1<Seq1,Seq2OrOperation,OperationOrInserter>             \
0132         , name##2<Seq1,Seq2OrOperation,OperationOrInserter,Inserter>    \
0133         >::type type;                                                   \
0134 };                                                                      \
0135 BOOST_MPL_AUX_NA_SPEC(4, name)                                          \
0136 /**/
0137
0138 AUX778076_TRANSFORM_DEF(transform)
0139 AUX778076_TRANSFORM_DEF(reverse_transform)
0140
0141 #undef AUX778076_TRANSFORM_DEF
0142
0143 }}
0144
0145 #endif // BOOST_MPL_TRANSFORM_HPP_INCLUDED