Chris@16: /*=============================================================================
Chris@16:     Copyright (c) 2007-2008 Tobias Schwinger
Chris@16:   
Chris@16:     Use modification and distribution are subject to the Boost Software 
Chris@16:     License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16:     http://www.boost.org/LICENSE_1_0.txt).  
Chris@16: ==============================================================================*/
Chris@16: 
Chris@16: #ifndef BOOST_FUNCTIONAL_FORWARD_ADAPTER_HPP_INCLUDED
Chris@16: #   ifndef BOOST_PP_IS_ITERATING
Chris@16: 
Chris@16: #   include <boost/config.hpp>
Chris@16: #   include <boost/detail/workaround.hpp>
Chris@16: 
Chris@16: #   include <boost/preprocessor/iteration/iterate.hpp>
Chris@16: #   include <boost/preprocessor/repetition/enum_params.hpp>
Chris@16: #   include <boost/preprocessor/repetition/enum_binary_params.hpp>
Chris@16: #   include <boost/preprocessor/facilities/intercept.hpp>
Chris@16: #   include <boost/preprocessor/arithmetic/dec.hpp>
Chris@16: 
Chris@16: #   include <boost/utility/result_of.hpp>
Chris@16: 
Chris@16: #   ifndef BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY
Chris@16: #     define BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY 6
Chris@16: #   elif BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY < 3
Chris@16: #     undef  BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY
Chris@16: #     define BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY 3
Chris@16: #   endif
Chris@16: 
Chris@16: 
Chris@16: namespace boost 
Chris@16: {
Chris@16:     template< typename Function, int Arity_Or_MinArity = -1, int MaxArity = -1 >
Chris@16:     class forward_adapter;
Chris@16: 
Chris@16:     //----- ---- --- -- - -  -   -
Chris@16: 
Chris@16:     namespace detail
Chris@16:     {
Chris@16:         template< class MostDerived, typename Function, typename FunctionConst, 
Chris@16:             int Arity, int MinArity >
Chris@16:         struct forward_adapter_impl;
Chris@16: 
Chris@16:         struct forward_adapter_result
Chris@16:         {
Chris@16:             template< typename Sig > struct apply;
Chris@16: 
Chris@16:             // Utility metafunction for qualification adjustment on arguments
Chris@16:             template< typename T > struct q          { typedef T const t; };
Chris@16:             template< typename T > struct q<T const> { typedef T const t; };
Chris@16:             template< typename T > struct q<T &>     { typedef T       t; };
Chris@16: 
Chris@16:             // Utility metafunction to choose target function qualification
Chris@16:             template< typename T > struct c
Chris@16:             { typedef typename T::target_function_t t; };
Chris@16:             template< typename T > struct c<T&      >
Chris@16:             { typedef typename T::target_function_t t; };
Chris@16:             template< typename T > struct c<T const >
Chris@16:             { typedef typename T::target_function_const_t t; };
Chris@16:             template< typename T > struct c<T const&>
Chris@16:             { typedef typename T::target_function_const_t t; };
Chris@16:         };
Chris@16:     }
Chris@16: 
Chris@16: #   define BOOST_TMP_MACRO(f,fn,fc) \
Chris@16:         boost::detail::forward_adapter_impl< \
Chris@16:             forward_adapter<f,Arity_Or_MinArity,MaxArity>, fn, fc, \
Chris@16:             (MaxArity!=-1? MaxArity :Arity_Or_MinArity!=-1? Arity_Or_MinArity \
Chris@16:                 :BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY), \
Chris@16:             (Arity_Or_MinArity!=-1? Arity_Or_MinArity : 0) >
Chris@16: 
Chris@16:     template< typename Function, int Arity_Or_MinArity, int MaxArity >
Chris@16:     class forward_adapter
Chris@16:         : public BOOST_TMP_MACRO(Function,Function,Function const)
Chris@16:         , private Function
Chris@16:     {
Chris@16:       public:
Chris@16:         forward_adapter(Function const& f = Function()) 
Chris@16:           : Function(f) 
Chris@16:         { }
Chris@16: 
Chris@16:         typedef Function        target_function_t;
Chris@16:         typedef Function const  target_function_const_t;
Chris@16: 
Chris@16:         Function       & target_function()       { return *this; }
Chris@16:         Function const & target_function() const { return *this; }
Chris@16: 
Chris@16:         template< typename Sig > struct result
Chris@16:             : detail::forward_adapter_result::template apply<Sig>
Chris@16:         { };
Chris@16: 
Chris@16:         using BOOST_TMP_MACRO(Function,Function, Function const)::operator();
Chris@16:     };
Chris@16:     template< typename Function, int Arity_Or_MinArity, int MaxArity >
Chris@16:     class forward_adapter< Function const, Arity_Or_MinArity, MaxArity >
Chris@16:         : public BOOST_TMP_MACRO(Function const, Function const, Function const)
Chris@16:         , private Function
Chris@16:     {
Chris@16:       public:
Chris@16:         forward_adapter(Function const& f = Function())
Chris@16:           : Function(f) 
Chris@16:         { }
Chris@16: 
Chris@16:         typedef Function const target_function_t;
Chris@16:         typedef Function const target_function_const_t;
Chris@16: 
Chris@16:         Function const & target_function() const { return *this; }
Chris@16: 
Chris@16:         template< typename Sig > struct result
Chris@16:             : detail::forward_adapter_result::template apply<Sig>
Chris@16:         { };
Chris@16: 
Chris@16:         using BOOST_TMP_MACRO(Function const,Function const, Function const)
Chris@16:             ::operator();
Chris@16:     };
Chris@16:     template< typename Function, int Arity_Or_MinArity, int MaxArity >
Chris@16:     class forward_adapter< Function &, Arity_Or_MinArity, MaxArity >
Chris@16:         : public BOOST_TMP_MACRO(Function&, Function, Function)
Chris@16:     {
Chris@16:         Function& ref_function;
Chris@16:       public:
Chris@16:         forward_adapter(Function& f)
Chris@16:           : ref_function(f) 
Chris@16:         { }
Chris@16: 
Chris@16:         typedef Function target_function_t;
Chris@16:         typedef Function target_function_const_t;
Chris@16: 
Chris@16:         Function & target_function() const { return this->ref_function; }
Chris@16: 
Chris@16:         template< typename Sig > struct result
Chris@16:             : detail::forward_adapter_result::template apply<Sig>
Chris@16:         { };
Chris@16: 
Chris@16:         using BOOST_TMP_MACRO(Function&, Function, Function)::operator();
Chris@16:     }; 
Chris@16: 
Chris@16:     #undef BOOST_TMP_MACRO
Chris@16: 
Chris@16:     namespace detail
Chris@16:     {
Chris@16:         template< class Self >
Chris@16:         struct forward_adapter_result::apply< Self() >
Chris@16:             : boost::result_of< BOOST_DEDUCED_TYPENAME c<Self>::t() >
Chris@16:         { };
Chris@16: 
Chris@16:         template< class MD, class F, class FC >
Chris@16:         struct forward_adapter_impl<MD,F,FC,0,0>
Chris@16:         {
Chris@16:             inline typename boost::result_of< FC() >::type
Chris@16:             operator()() const
Chris@16:             {
Chris@16:                 return static_cast<MD const*>(this)->target_function()();
Chris@16:             }
Chris@16: 
Chris@16:             inline typename boost::result_of< F() >::type
Chris@16:             operator()()
Chris@16:             {
Chris@16:                 return static_cast<MD*>(this)->target_function()();
Chris@16:             }
Chris@16: 
Chris@16:         // closing brace gets generated by preprocessing code, below
Chris@16: 
Chris@16: #       define BOOST_TMP_MACRO(tpl_params,arg_types,params,args)              \
Chris@16:             template< tpl_params >                                             \
Chris@16:             inline typename boost::result_of< FC(arg_types) >::type            \
Chris@16:             operator()(params) const                                           \
Chris@16:             {                                                                  \
Chris@16:                 return static_cast<MD const*>(this)->target_function()(args);  \
Chris@16:             }                                                                  \
Chris@16:             template< tpl_params >                                             \
Chris@16:             inline typename boost::result_of< F(arg_types)>::type              \
Chris@16:             operator()(params)                                                 \
Chris@16:             {                                                                  \
Chris@16:                 return static_cast<MD*>(this)->target_function()(args);        \
Chris@16:             }
Chris@16: 
Chris@16: #       // This is the total number of iterations we need
Chris@16: #       define count ((1 << BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY+1)-2)
Chris@16: 
Chris@16: #       // Chain file iteration to virtually one loop
Chris@16: #       if BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY <= 7
Chris@16: #         define limit1 count
Chris@16: #         define limit2 0
Chris@16: #         define limit3 0
Chris@16: #       else
Chris@16: #         if BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY <= 15
Chris@16: #           define limit1 (count >> 8)
Chris@16: #           define limit2 255
Chris@16: #           define limit3 0
Chris@16: #         else
Chris@16: #           define limit1 (count >> 16)
Chris@16: #           define limit2 255
Chris@16: #           define limit3 255
Chris@16: #         endif
Chris@16: #       endif
Chris@16: 
Chris@16: #       define N 0
Chris@16: 
Chris@16: #       define  BOOST_PP_FILENAME_1 <boost/functional/forward_adapter.hpp>
Chris@16: #       define  BOOST_PP_ITERATION_LIMITS (0,limit1)
Chris@16: #       include BOOST_PP_ITERATE()
Chris@16: 
Chris@16: #       undef N
Chris@16: #       undef limit3
Chris@16: #       undef limit2
Chris@16: #       undef limit1
Chris@16: #       undef count
Chris@16: #       undef BOOST_TMP_MACRO
Chris@16: 
Chris@16:         };
Chris@16: 
Chris@16:     } // namespace detail
Chris@16: 
Chris@16:     template<class F, int A0, int A1>
Chris@16:     struct result_of<boost::forward_adapter<F,A0,A1> const ()>
Chris@16:         : boost::detail::forward_adapter_result::template apply<
Chris@16:             boost::forward_adapter<F,A0,A1> const () >
Chris@16:     { };
Chris@16:     template<class F, int A0, int A1>
Chris@16:     struct result_of<boost::forward_adapter<F,A0,A1>()>
Chris@16:         : boost::detail::forward_adapter_result::template apply<
Chris@16:             boost::forward_adapter<F,A0,A1>() >
Chris@16:     { };
Chris@16:     template<class F, int A0, int A1>
Chris@16:     struct result_of<boost::forward_adapter<F,A0,A1> const& ()>
Chris@16:         : boost::detail::forward_adapter_result::template apply<
Chris@16:             boost::forward_adapter<F,A0,A1> const () >
Chris@16:     { };
Chris@16:     template<class F, int A0, int A1>
Chris@16:     struct result_of<boost::forward_adapter<F,A0,A1>& ()>
Chris@16:         : boost::detail::forward_adapter_result::template apply<
Chris@16:             boost::forward_adapter<F,A0,A1>() >
Chris@16:     { };
Chris@16: }
Chris@16: 
Chris@16: #       define BOOST_FUNCTIONAL_FORWARD_ADAPTER_HPP_INCLUDED
Chris@16: 
Chris@16: #   elif BOOST_PP_ITERATION_DEPTH() == 1 && limit2
Chris@16: #     define  BOOST_PP_FILENAME_2 <boost/functional/forward_adapter.hpp>
Chris@16: #     define  BOOST_PP_ITERATION_LIMITS (0,limit2)
Chris@16: #     include BOOST_PP_ITERATE()
Chris@16: #   elif BOOST_PP_ITERATION_DEPTH() == 2 && limit3
Chris@16: #     define  BOOST_PP_FILENAME_3 <boost/functional/forward_adapter.hpp>
Chris@16: #     define  BOOST_PP_ITERATION_LIMITS (0,limit3)
Chris@16: #     include BOOST_PP_ITERATE()
Chris@16: 
Chris@16: #   else
Chris@16: 
Chris@16: #     // I is the loop counter
Chris@16: #     if limit2 && limit3
Chris@16: #       define I (BOOST_PP_ITERATION_1 << 16 | BOOST_PP_ITERATION_2 << 8 | \
Chris@16:             BOOST_PP_ITERATION_3)
Chris@16: #     elif limit2
Chris@16: #       define I (BOOST_PP_ITERATION_1 << 8 | BOOST_PP_ITERATION_2)
Chris@16: #     else
Chris@16: #       define I BOOST_PP_ITERATION_1
Chris@16: #     endif
Chris@16: 
Chris@16: #     if I < count
Chris@16: 
Chris@16: #       // Done for this arity? Increment N
Chris@16: #       if (I+2 >> N+1) 
Chris@16: #         if N == 0
Chris@16: #           undef N
Chris@16: #           define N 1
Chris@16: #         elif N == 1
Chris@16: #           undef N
Chris@16: #           define N 2
Chris@16: #         elif N == 2
Chris@16: #           undef N
Chris@16: #           define N 3
Chris@16: #         elif N == 3
Chris@16: #           undef N
Chris@16: #           define N 4
Chris@16: #         elif N == 4
Chris@16: #           undef N
Chris@16: #           define N 5
Chris@16: #         elif N == 5
Chris@16: #           undef N
Chris@16: #           define N 6
Chris@16: #         elif N == 6
Chris@16: #           undef N
Chris@16: #           define N 7
Chris@16: #         elif N == 7
Chris@16: #           undef N
Chris@16: #           define N 8
Chris@16: #         elif N == 8
Chris@16: #           undef N
Chris@16: #           define N 9
Chris@16: #         elif N == 9
Chris@16: #           undef N
Chris@16: #           define N 10
Chris@16: #         elif N == 10
Chris@16: #           undef N
Chris@16: #           define N 11
Chris@16: #         elif N == 11
Chris@16: #           undef N
Chris@16: #           define N 12
Chris@16: #         elif N == 12
Chris@16: #           undef N
Chris@16: #           define N 13
Chris@16: #         elif N == 13
Chris@16: #           undef N
Chris@16: #           define N 14
Chris@16: #         elif N == 14
Chris@16: #           undef N
Chris@16: #           define N 15
Chris@16: #         elif N == 15
Chris@16: #           undef N
Chris@16: #           define N 16
Chris@16: #         endif
Chris@16: 
Chris@16:         };
Chris@16: 
Chris@16:         template< class Self, BOOST_PP_ENUM_PARAMS(N,typename T) >
Chris@16:         struct forward_adapter_result::apply< Self(BOOST_PP_ENUM_PARAMS(N,T)) >
Chris@16:             : boost::result_of< 
Chris@16:                 BOOST_DEDUCED_TYPENAME c<Self>::t(BOOST_PP_ENUM_BINARY_PARAMS(N, 
Chris@16:                       typename q<T,>::t& BOOST_PP_INTERCEPT)) >
Chris@16:         { };
Chris@16: 
Chris@16:         template< class MD, class F, class FC >
Chris@16:         struct forward_adapter_impl<MD,F,FC,BOOST_PP_DEC(N),N>
Chris@16:         {
Chris@16:             template< BOOST_PP_ENUM_PARAMS(N,typename T) >
Chris@16:             inline typename boost::result_of< F(
Chris@16:                 BOOST_PP_ENUM_BINARY_PARAMS(N,T,& BOOST_PP_INTERCEPT)) >::type
Chris@16:             operator()(BOOST_PP_ENUM_BINARY_PARAMS(N,T,& BOOST_PP_INTERCEPT));
Chris@16:         };
Chris@16: 
Chris@16:         template< class MD, class F, class FC, int MinArity >
Chris@16:         struct forward_adapter_impl<MD,F,FC,N,MinArity>
Chris@16:             : forward_adapter_impl<MD,F,FC,BOOST_PP_DEC(N),MinArity>
Chris@16:         {
Chris@16:             using forward_adapter_impl<MD,F,FC,BOOST_PP_DEC(N),MinArity>::operator();
Chris@16: 
Chris@16: #       endif
Chris@16: 
Chris@16: #       // Zero based count for each arity would be I-(1<<N)+2, but we don't
Chris@16: #       // need it, unless we need a nicer order.
Chris@16: 
Chris@16: #       // Macros for the parameter's type modifiers.
Chris@16: #       if I & 0x000001
Chris@16: #         define PT0 T0 &
Chris@16: #       else
Chris@16: #         define PT0 T0 const &
Chris@16: #       endif
Chris@16: #       if I & 0x000002
Chris@16: #         define PT1 T1 &
Chris@16: #       else
Chris@16: #         define PT1 T1 const &
Chris@16: #       endif
Chris@16: #       if I & 0x000004
Chris@16: #         define PT2 T2 &
Chris@16: #       else
Chris@16: #         define PT2 T2 const &
Chris@16: #       endif
Chris@16: #       if I & 0x000008
Chris@16: #         define PT3 T3 &
Chris@16: #       else
Chris@16: #         define PT3 T3 const &
Chris@16: #       endif
Chris@16: #       if I & 0x000010
Chris@16: #         define PT4 T4 &
Chris@16: #       else
Chris@16: #         define PT4 T4 const &
Chris@16: #       endif
Chris@16: #       if I & 0x000020
Chris@16: #         define PT5 T5 &
Chris@16: #       else
Chris@16: #         define PT5 T5 const &
Chris@16: #       endif
Chris@16: #       if I & 0x000040
Chris@16: #         define PT6 T6 &
Chris@16: #       else
Chris@16: #         define PT6 T6 const &
Chris@16: #       endif
Chris@16: #       if I & 0x000080
Chris@16: #         define PT7 T7 &
Chris@16: #       else
Chris@16: #         define PT7 T7 const &
Chris@16: #       endif
Chris@16: #       if I & 0x000100
Chris@16: #         define PT8 T8 &
Chris@16: #       else
Chris@16: #         define PT8 T8 const &
Chris@16: #       endif
Chris@16: #       if I & 0x000200
Chris@16: #         define PT9 T9 &
Chris@16: #       else
Chris@16: #         define PT9 T9 const &
Chris@16: #       endif
Chris@16: #       if I & 0x000400
Chris@16: #         define PT10 T10 &
Chris@16: #       else
Chris@16: #         define PT10 T10 const &
Chris@16: #       endif
Chris@16: #       if I & 0x000800
Chris@16: #         define PT11 T11 &
Chris@16: #       else
Chris@16: #         define PT11 T11 const &
Chris@16: #       endif
Chris@16: #       if I & 0x001000
Chris@16: #         define PT12 T12 &
Chris@16: #       else
Chris@16: #         define PT12 T12 const &
Chris@16: #       endif
Chris@16: #       if I & 0x002000
Chris@16: #         define PT13 T13 &
Chris@16: #       else
Chris@16: #         define PT13 T13 const &
Chris@16: #       endif
Chris@16: #       if I & 0x004000
Chris@16: #         define PT14 T14 &
Chris@16: #       else
Chris@16: #         define PT14 T14 const &
Chris@16: #       endif
Chris@16: #       if I & 0x008000
Chris@16: #         define PT15 T15 &
Chris@16: #       else
Chris@16: #         define PT15 T15 const &
Chris@16: #       endif
Chris@16: 
Chris@16: #       if BOOST_WORKAROUND(BOOST_MSVC,BOOST_TESTED_AT(1400)) 
Chris@16:             template< BOOST_PP_ENUM_PARAMS(N,typename T) >
Chris@16:             inline typename boost::result_of<  FC(BOOST_PP_ENUM_PARAMS(N,PT)) 
Chris@16:                 >::type
Chris@16:             operator()(BOOST_PP_ENUM_BINARY_PARAMS(N,PT,a)) const
Chris@16:             {
Chris@16:                 return static_cast<MD const* const>(this)
Chris@16:                     ->target_function()(BOOST_PP_ENUM_PARAMS(N,a));
Chris@16:             }
Chris@16:             template< BOOST_PP_ENUM_PARAMS(N,typename T) >
Chris@16:             inline typename boost::result_of<  F(BOOST_PP_ENUM_PARAMS(N,PT))
Chris@16:                 >::type
Chris@16:             operator()(BOOST_PP_ENUM_BINARY_PARAMS(N,PT,a))
Chris@16:             {
Chris@16:                 return static_cast<MD* const>(this)
Chris@16:                     ->target_function()(BOOST_PP_ENUM_PARAMS(N,a));
Chris@16:             }
Chris@16: #       else
Chris@16:         BOOST_TMP_MACRO(BOOST_PP_ENUM_PARAMS(N,typename T),
Chris@16:             BOOST_PP_ENUM_PARAMS(N,PT), BOOST_PP_ENUM_BINARY_PARAMS(N,PT,a),
Chris@16:             BOOST_PP_ENUM_PARAMS(N,a) )
Chris@16:         // ...generates uglier code but is faster - it caches ENUM_*
Chris@16: #       endif
Chris@16: 
Chris@16: #       undef PT0
Chris@16: #       undef PT1
Chris@16: #       undef PT2
Chris@16: #       undef PT3
Chris@16: #       undef PT4
Chris@16: #       undef PT5
Chris@16: #       undef PT6
Chris@16: #       undef PT7
Chris@16: #       undef PT8
Chris@16: #       undef PT9
Chris@16: #       undef PT10
Chris@16: #       undef PT11
Chris@16: #       undef PT12
Chris@16: #       undef PT13
Chris@16: #       undef PT14
Chris@16: #       undef PT15
Chris@16: 
Chris@16: #     endif // I < count
Chris@16: 
Chris@16: #     undef I
Chris@16: #   endif // defined(BOOST_PP_IS_ITERATING)
Chris@16: 
Chris@16: #endif // include guard
Chris@16: