wiselib.stable/util/delegates/detail/delegate_template.hpp

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/*
   (c) Sergey Ryazanov (http://home.onego.ru/~ryazanov)

   Template file. May be included many times with different predefined macros.
*/
#if SRUTIL_DELEGATE_PARAM_COUNT > 0
#define SRUTIL_DELEGATE_SEPARATOR ,
#else
#define SRUTIL_DELEGATE_SEPARATOR
#endif

// see BOOST_JOIN for explanation
#define SRUTIL_DELEGATE_JOIN_MACRO( X, Y) SRUTIL_DELEGATE_DO_JOIN( X, Y )
#define SRUTIL_DELEGATE_DO_JOIN( X, Y ) SRUTIL_DELEGATE_DO_JOIN2(X,Y)
#define SRUTIL_DELEGATE_DO_JOIN2( X, Y ) X##Y

// namespace srutil
// {
#ifdef SRUTIL_DELEGATE_PREFERRED_SYNTAX
#define SRUTIL_DELEGATE_CLASS_NAME delegate
#define SRUTIL_DELEGATE_INVOKER_CLASS_NAME delegate_invoker
#else
#define SRUTIL_DELEGATE_CLASS_NAME SRUTIL_DELEGATE_JOIN_MACRO(delegate,SRUTIL_DELEGATE_PARAM_COUNT)
#define SRUTIL_DELEGATE_INVOKER_CLASS_NAME SRUTIL_DELEGATE_JOIN_MACRO(delegate_invoker,SRUTIL_DELEGATE_PARAM_COUNT)
   template <typename R SRUTIL_DELEGATE_SEPARATOR SRUTIL_DELEGATE_TEMPLATE_PARAMS>
   class SRUTIL_DELEGATE_INVOKER_CLASS_NAME;
#endif

   template <typename R SRUTIL_DELEGATE_SEPARATOR SRUTIL_DELEGATE_TEMPLATE_PARAMS>
#ifdef SRUTIL_DELEGATE_PREFERRED_SYNTAX
   class SRUTIL_DELEGATE_CLASS_NAME<R (SRUTIL_DELEGATE_TEMPLATE_ARGS)>
#else
   class SRUTIL_DELEGATE_CLASS_NAME
#endif
   {
   public:
      typedef R return_type;
#ifdef SRUTIL_DELEGATE_PREFERRED_SYNTAX
      typedef return_type (SRUTIL_DELEGATE_CALLTYPE *signature_type)(SRUTIL_DELEGATE_TEMPLATE_ARGS);
      typedef SRUTIL_DELEGATE_INVOKER_CLASS_NAME<signature_type> invoker_type;
#else
      typedef return_type (SRUTIL_DELEGATE_CALLTYPE *signature_type)(SRUTIL_DELEGATE_TEMPLATE_ARGS);
      typedef SRUTIL_DELEGATE_INVOKER_CLASS_NAME<R SRUTIL_DELEGATE_SEPARATOR SRUTIL_DELEGATE_TEMPLATE_ARGS> invoker_type;
#endif

      SRUTIL_DELEGATE_CLASS_NAME()
         : object_ptr(0)
         , stub_ptr(0)
      {}

      template <return_type (*TMethod)(SRUTIL_DELEGATE_TEMPLATE_ARGS)>
      static SRUTIL_DELEGATE_CLASS_NAME from_function()
      {
         return from_stub(0, &function_stub<TMethod>);
      }

      template <class T, return_type (T::*TMethod)(SRUTIL_DELEGATE_TEMPLATE_ARGS)>
      static SRUTIL_DELEGATE_CLASS_NAME from_method(T* object_ptr)
      {
         return from_stub(object_ptr, &method_stub<T, TMethod>);
      }

      template <class T, return_type (T::*TMethod)(SRUTIL_DELEGATE_TEMPLATE_ARGS) const>
      static SRUTIL_DELEGATE_CLASS_NAME from_const_method(T const* object_ptr)
      {
         return from_stub(const_cast<T*>(object_ptr), &const_method_stub<T, TMethod>);
      }

      return_type operator()(SRUTIL_DELEGATE_PARAMS) const
      {
         return (*stub_ptr)(object_ptr SRUTIL_DELEGATE_SEPARATOR SRUTIL_DELEGATE_ARGS);
      }

      operator bool () const
      {
         return stub_ptr != 0;
      }

      bool operator!() const
      {
         return !(operator bool());
      }

      void* obj_ptr() { return object_ptr; };

   private:
      
      typedef return_type (SRUTIL_DELEGATE_CALLTYPE *stub_type)(void* object_ptr SRUTIL_DELEGATE_SEPARATOR SRUTIL_DELEGATE_PARAMS);

      void* object_ptr;
      stub_type stub_ptr;

      static SRUTIL_DELEGATE_CLASS_NAME from_stub(void* object_ptr, stub_type stub_ptr)
      {
         SRUTIL_DELEGATE_CLASS_NAME d;
         d.object_ptr = object_ptr;
         d.stub_ptr = stub_ptr;
         return d;
      }

      template <return_type (*TMethod)(SRUTIL_DELEGATE_TEMPLATE_ARGS)>
      static return_type SRUTIL_DELEGATE_CALLTYPE function_stub(void* SRUTIL_DELEGATE_SEPARATOR SRUTIL_DELEGATE_PARAMS)
      {
         return (TMethod)(SRUTIL_DELEGATE_ARGS);
      }

      template <class T, return_type (T::*TMethod)(SRUTIL_DELEGATE_TEMPLATE_ARGS)>
      static return_type SRUTIL_DELEGATE_CALLTYPE method_stub(void* object_ptr SRUTIL_DELEGATE_SEPARATOR SRUTIL_DELEGATE_PARAMS)
      {
         T* p = static_cast<T*>(object_ptr);
         return (p->*TMethod)(SRUTIL_DELEGATE_ARGS);
      }

      template <class T, return_type (T::*TMethod)(SRUTIL_DELEGATE_TEMPLATE_ARGS) const>
      static return_type SRUTIL_DELEGATE_CALLTYPE const_method_stub(void* object_ptr SRUTIL_DELEGATE_SEPARATOR SRUTIL_DELEGATE_PARAMS)
      {
         T const* p = static_cast<T*>(object_ptr);
         return (p->*TMethod)(SRUTIL_DELEGATE_ARGS);
      }
   };

   template <typename R SRUTIL_DELEGATE_SEPARATOR SRUTIL_DELEGATE_TEMPLATE_PARAMS>
#ifdef SRUTIL_DELEGATE_PREFERRED_SYNTAX
   class SRUTIL_DELEGATE_INVOKER_CLASS_NAME<R (SRUTIL_DELEGATE_TEMPLATE_ARGS)>
#else
   class SRUTIL_DELEGATE_INVOKER_CLASS_NAME
#endif
   {
      SRUTIL_DELEGATE_INVOKER_DATA

   public:
      SRUTIL_DELEGATE_INVOKER_CLASS_NAME(SRUTIL_DELEGATE_PARAMS)
#if SRUTIL_DELEGATE_PARAM_COUNT > 0
         :
#endif
         SRUTIL_DELEGATE_INVOKER_INITIALIZATION_LIST
      {
      }

      template <class TDelegate>
      R operator()(TDelegate d) const
      {
         return d(SRUTIL_DELEGATE_ARGS);
      }
   };
// }

#undef SRUTIL_DELEGATE_CLASS_NAME
#undef SRUTIL_DELEGATE_SEPARATOR
#undef SRUTIL_DELEGATE_JOIN_MACRO
#undef SRUTIL_DELEGATE_DO_JOIN
#undef SRUTIL_DELEGATE_DO_JOIN2