ceph/src/boost/boost/fusion/functional/invocation/invoke_function_object.hpp

   1 /*=============================================================================
   2     Copyright (c) 2005-2006 Joao Abecasis
   3     Copyright (c) 2006-2007 Tobias Schwinger
   4
   5     Use modification and distribution are subject to the Boost Software
   6     License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
   7     http://www.boost.org/LICENSE_1_0.txt).
   8 ==============================================================================*/
   9
  10 #if !defined(BOOST_FUSION_FUNCTIONAL_INVOCATION_INVOKE_FUNCTION_OBJECT_HPP_INCLUDED)
  11 #if !defined(BOOST_PP_IS_ITERATING)
  12
  13 #include <boost/preprocessor/cat.hpp>
  14 #include <boost/preprocessor/iteration/iterate.hpp>
  15 #include <boost/preprocessor/arithmetic/dec.hpp>
  16 #include <boost/preprocessor/repetition/repeat_from_to.hpp>
  17 #include <boost/preprocessor/repetition/enum.hpp>
  18 #include <boost/preprocessor/repetition/enum_params.hpp>
  19
  20 #include <boost/utility/result_of.hpp>
  21 #include <boost/core/enable_if.hpp>
  22
  23 #include <boost/type_traits/remove_reference.hpp>
  24 #include <boost/type_traits/remove_const.hpp>
  25
  26 #include <boost/fusion/support/category_of.hpp>
  27 #include <boost/fusion/sequence/intrinsic/size.hpp>
  28 #include <boost/fusion/sequence/intrinsic/at.hpp>
  29 #include <boost/fusion/sequence/intrinsic/begin.hpp>
  30 #include <boost/fusion/iterator/next.hpp>
  31 #include <boost/fusion/iterator/deref.hpp>
  32 #include <boost/fusion/functional/invocation/limits.hpp>
  33
  34 namespace boost { namespace fusion
  35 {
  36     namespace detail
  37     {
  38         template<
  39             class Function, class Sequence,
  40             int N = result_of::size<Sequence>::value,
  41             bool RandomAccess = traits::is_random_access<Sequence>::value,
  42             typename Enable = void
  43             >
  44         struct invoke_function_object_impl;
  45
  46         template <class Sequence, int N>
  47         struct invoke_function_object_param_types;
  48
  49         #define  BOOST_PP_FILENAME_1 \
  50             <boost/fusion/functional/invocation/invoke_function_object.hpp>
  51         #define  BOOST_PP_ITERATION_LIMITS \
  52             (0, BOOST_FUSION_INVOKE_FUNCTION_OBJECT_MAX_ARITY)
  53         #include BOOST_PP_ITERATE()
  54     }
  55
  56     namespace result_of
  57     {
  58         template <class Function, class Sequence, class Enable = void>
  59         struct invoke_function_object;
  60
  61         template <class Function, class Sequence>
  62         struct invoke_function_object<Function, Sequence,
  63             typename enable_if_has_type<
  64                 typename detail::invoke_function_object_impl<
  65                     typename boost::remove_reference<Function>::type, Sequence
  66                 >::result_type
  67             >::type>
  68         {
  69             typedef typename detail::invoke_function_object_impl<
  70                 typename boost::remove_reference<Function>::type, Sequence
  71                 >::result_type type;
  72         };
  73     }
  74
  75     template <class Function, class Sequence>
  76     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  77     inline typename result_of::invoke_function_object<Function,Sequence>::type
  78     invoke_function_object(Function f, Sequence & s)
  79     {
  80         return detail::invoke_function_object_impl<
  81                 typename boost::remove_reference<Function>::type,Sequence
  82             >::call(f,s);
  83     }
  84
  85     template <class Function, class Sequence>
  86     BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  87     inline typename result_of::invoke_function_object<Function,Sequence const>::type
  88     invoke_function_object(Function f, Sequence const & s)
  89     {
  90         return detail::invoke_function_object_impl<
  91                 typename boost::remove_reference<Function>::type,Sequence const
  92             >::call(f,s);
  93     }
  94
  95 }}
  96
  97 #define BOOST_FUSION_FUNCTIONAL_INVOCATION_INVOKE_FUNCTION_OBJECT_HPP_INCLUDED
  98 #else // defined(BOOST_PP_IS_ITERATING)
  99 ///////////////////////////////////////////////////////////////////////////////
 100 //
 101 //  Preprocessor vertical repetition code
 102 //
 103 ///////////////////////////////////////////////////////////////////////////////
 104 #define N BOOST_PP_ITERATION()
 105
 106 #define M(z,j,data)                                                             \
 107         typename result_of::at_c<Sequence,j>::type
 108
 109         template <class Function, class Sequence>
 110         struct invoke_function_object_impl<Function,Sequence,N,true,
 111             typename enable_if_has_type<
 112                 typename boost::result_of<Function (BOOST_PP_ENUM(N,M,~)) >::type
 113             >::type>
 114         {
 115         public:
 116
 117             typedef typename boost::result_of<
 118                 Function (BOOST_PP_ENUM(N,M,~)) >::type result_type;
 119 #undef M
 120
 121 #if N > 0
 122
 123             template <class F>
 124             BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
 125             static inline result_type
 126             call(F & f, Sequence & s)
 127             {
 128 #define M(z,j,data) fusion::at_c<j>(s)
 129                 return f( BOOST_PP_ENUM(N,M,~) );
 130 #undef M
 131             }
 132
 133 #else
 134
 135             template <class F>
 136             BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
 137             static inline result_type
 138             call(F & f, Sequence & /*s*/)
 139             {
 140                 return f();
 141             }
 142
 143 #endif
 144
 145         };
 146
 147 #define M(z,j,data)                                                             \
 148             typename invoke_function_object_param_types<Sequence,N>::T ## j
 149
 150         template <class Function, class Sequence>
 151         struct invoke_function_object_impl<Function,Sequence,N,false,
 152             typename enable_if_has_type<
 153                 typename boost::result_of<Function (BOOST_PP_ENUM(N,M,~)) >::type
 154             >::type>
 155 #undef M
 156         {
 157         private:
 158             typedef invoke_function_object_param_types<Sequence,N> seq;
 159         public:
 160             typedef typename boost::result_of<
 161                 Function (BOOST_PP_ENUM_PARAMS(N,typename seq::T))
 162                 >::type result_type;
 163
 164 #if N > 0
 165
 166             template <class F>
 167             BOOST_CXX14_CONSTEXPR BOOST_FUSION_GPU_ENABLED
 168             static inline result_type
 169             call(F & f, Sequence & s)
 170             {
 171                 typename seq::I0 i0 = fusion::begin(s);
 172 #define M(z,j,data)                                                             \
 173             typename seq::I##j i##j =                                          \
 174                 fusion::next(BOOST_PP_CAT(i,BOOST_PP_DEC(j)));
 175                 BOOST_PP_REPEAT_FROM_TO(1,N,M,~)
 176 #undef M
 177                 return f( BOOST_PP_ENUM_PARAMS(N,*i) );
 178             }
 179
 180 #else
 181
 182             template <class F>
 183             BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
 184             static inline result_type
 185             call(F & f, Sequence & /*s*/)
 186             {
 187                 return f();
 188             }
 189
 190 #endif
 191
 192         };
 193
 194         template <class Sequence>
 195         struct invoke_function_object_param_types<Sequence,N>
 196         {
 197 #if N > 0
 198             typedef typename result_of::begin<Sequence>::type I0;
 199             typedef typename result_of::deref<I0>::type T0;
 200
 201 #define M(z,i,data)                                                             \
 202             typedef typename result_of::next<                                  \
 203                 BOOST_PP_CAT(I,BOOST_PP_DEC(i))>::type I##i;                   \
 204             typedef typename result_of::deref<I##i>::type T##i;
 205
 206             BOOST_PP_REPEAT_FROM_TO(1,N,M,~)
 207 #undef M
 208 #endif
 209         };
 210
 211 #undef N
 212 #endif // defined(BOOST_PP_IS_ITERATING)
 213 #endif
 214