include/functionInfo.h

   1 /***************************************************************************
   2  *   This file is part of KWorship.                                        *
   3  *   Copyright 2008 James Hogan <james@albanarts.com>                      *
   4  *                                                                         *
   5  *   KWorship is free software: you can redistribute it and/or modify      *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation, either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   KWorship is distributed in the hope that it will be useful,           *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with KWorship.  If not, write to the Free Software Foundation,  *
  17  *   Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.   *
  18  ***************************************************************************/
  19
  20 #ifndef _functionInfo_h_
  21 #define _functionInfo_h_
  22
  23 #include "repeatMacros.h"
  24
  25 namespace meta
  26 {
  27   template <typename F>
  28   struct Tuple;
  29 #define META_TUPLE(ARGS) ::meta::Tuple<void (*)ARGS>
  30
  31   template <typename F, int P>
  32   struct ParameterInfo;
  33
  34   // Number of arguments of a function
  35   template <typename F>
  36   struct FunctionInfo;
  37
  38
  39   // Macros to make this easier
  40
  41   // Parameter list, e.g. "typename Param0; typename Param1;"
  42 #define FUNCTION_INFO_PARAM_INSTANTIATION(A,B,N)  Param##N param##N;
  43 #define FUNCTION_INFO_PARAM_INSTANTIATIONS(N) REPEATB(FUNCTION_INFO_PARAM_INSTANTIATION,0,0,N)
  44   // Parameter list, e.g. "typename Param0, typename Param1"
  45 #define FUNCTION_INFO_TEMPLATE_PARAMETER(A,B,N)  typename Param##N
  46 #define FUNCTION_INFO_TEMPLATE_PARAMETERS(N) REPEATB_LIST(FUNCTION_INFO_TEMPLATE_PARAMETER,0,0,N)
  47   // Parameter list, e.g. ", typename Param0, typename Param1"
  48 #define FUNCTION_INFO_TEMPLATE_PARAMETER_TAIL(A,B,N)  , typename Param##N
  49 #define FUNCTION_INFO_TEMPLATE_PARAMETERS_TAIL(N) REPEATB(FUNCTION_INFO_TEMPLATE_PARAMETER_TAIL,0,0,N)
  50   // Argument list, e.g. "(Param0 param0, Param1 param1)"
  51 #define FUNCTION_INFO_PARAMETER(A,B,N)   Param##N param##N
  52 #define FUNCTION_INFO_PARAMETERS(N) \
  53   ( REPEATB_LIST(FUNCTION_INFO_PARAMETER,0,0,N) )
  54   // Tail argument list, e.g. ", Param0, Param1"
  55 #define FUNCTION_INFO_PARAMETER_TAIL(A,B,N) , Param##N
  56 #define FUNCTION_INFO_PARAMETERS_TAIL(N) \
  57   REPEATB(FUNCTION_INFO_PARAMETER_TAIL,0,0,N)
  58   // Argument list, e.g. "(param0, param1)"
  59 #define FUNCTION_INFO_ARGUMENT(A,B,N)   param##N
  60 #define FUNCTION_INFO_ARGUMENTS(N) \
  61   ( REPEATB_LIST(FUNCTION_INFO_ARGUMENT,0,0,N) )
  62   // Unpack Argument list, e.g. "(P.param0, P.param1)"
  63 #define FUNCTION_INFO_UNPACK_ARGUMENT(P,B,N)   (P).param##N
  64 #define FUNCTION_INFO_UNPACK_ARGUMENTS(P,N) \
  65   ( REPEATB_LIST(FUNCTION_INFO_UNPACK_ARGUMENT,P,0,N) )
  66
  67   // Parameter template instantiation
  68 #define PARAMETER_INFO(T,N) \
  69   template <FUNCTION_INFO_TEMPLATE_PARAMETERS(T) > \
  70   struct ParameterInfo<void (*)FUNCTION_INFO_PARAMETERS(T),N> \
  71   { \
  72     typedef Param##N Type; \
  73   };
  74
  75   // Function length template instantiation
  76 #define FUNCTION_INFO(N) \
  77   template <FUNCTION_INFO_TEMPLATE_PARAMETERS(N) > \
  78   struct Tuple<void (*)FUNCTION_INFO_PARAMETERS(N)> \
  79   { \
  80     enum \
  81     { \
  82       length = N \
  83     }; \
  84     struct Pack \
  85     { \
  86       /* A member for each item */ \
  87       FUNCTION_INFO_PARAM_INSTANTIATIONS(N) \
  88       /* Construct a new CTYPE using the pack as arguments */ \
  89       template <typename CTYPE> \
  90       CTYPE* construct() const \
  91       { \
  92         return new CTYPE FUNCTION_INFO_ARGUMENTS(N); \
  93       } \
  94     }; \
  95     static struct Pack pack FUNCTION_INFO_PARAMETERS(N) \
  96     { \
  97       Pack myPack = { REPEATB_LIST(FUNCTION_INFO_ARGUMENT,0,0,N) }; \
  98       return myPack; \
  99     } \
 100     template <int id> \
 101     struct Param : public ParameterInfo<void (*)FUNCTION_INFO_PARAMETERS(N), id> \
 102     { \
 103     }; \
 104     template <typename Ret> \
 105     struct Return \
 106     { \
 107       typedef Ret (Signiture)FUNCTION_INFO_PARAMETERS(N); \
 108       typedef Ret (*Pointer)FUNCTION_INFO_PARAMETERS(N); \
 109       typedef FunctionInfo<Pointer> Info; \
 110     }; \
 111     template <typename NewArg> \
 112     struct Unshift \
 113     { \
 114       typedef void (*Pointer)(NewArg FUNCTION_INFO_PARAMETERS_TAIL(N)); \
 115       typedef Tuple<Pointer> Info; \
 116     }; \
 117   }; \
 118   template <typename Ret FUNCTION_INFO_TEMPLATE_PARAMETERS_TAIL(N) > \
 119   struct FunctionInfo<Ret (*)FUNCTION_INFO_PARAMETERS(N)> \
 120   { \
 121     typedef Ret Return; \
 122     typedef Ret (*Pointer)FUNCTION_INFO_PARAMETERS(N); \
 123     typedef Tuple<void (*)FUNCTION_INFO_PARAMETERS(N)> Params; \
 124     template <typename FUNCTOR> \
 125     static Ret unpack(typename Params::Pack package) \
 126     { \
 127       return FUNCTOR::call FUNCTION_INFO_UNPACK_ARGUMENTS(package,N); \
 128     } \
 129     template <typename NewArg> \
 130     struct Unshift \
 131     { \
 132       typedef Ret (*Pointer)(NewArg FUNCTION_INFO_PARAMETERS_TAIL(N)); \
 133       typedef FunctionInfo<Pointer> Info; \
 134     }; \
 135   }; \
 136   REPEATA(PARAMETER_INFO, N, N)
 137
 138
 139   REPEAT(FUNCTION_INFO, 8)
 140
 141 #undef FUNCTION_INFO_PARAMETER
 142 #undef FUNCTION_INFO_PARAMETERS
 143 #undef FUNCTION_INFO_ARGUMENT
 144 #undef FUNCTION_INFO_POINTER_TYPE
 145 #undef PARAMETER_INFO
 146 #undef FUNCTION_INFO
 147 }
 148
 149 #endif // _functionInfo_h_
 150