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#include <iostream>
using namespace std;
 
class WVObject
{
protected:
    typedef bool (*EvalFun)(unsigned long);
 
    bool evalA (unsigned long id) const { return true; }
    bool evalB (unsigned long id) const { return false; }
 
    bool test (EvalFun fnctToEval) const
    {
        //hier der Zugriff auf die übergebene Methode
        bool res = (*fnctToEval) (4);
        return res;
    }
 
public:
    virtual void parse() = 0;
};
 
//WVKnoten.hpp
class WVKnoten : public WVObject
{
	public:
	void parse () { cout << test(&WVObject::evalA); }
};
 
int main() {
	WVKnoten obj;
	obj.parse();
	return 0;
}

prog.cpp: In member function ‘virtual void WVKnoten::parse()’:
prog.cpp:9:10: error: ‘bool WVObject::evalA(long unsigned int) const’ is protected
     bool evalA (unsigned long id) const { return true; }
          ^
prog.cpp:27:42: error: within this context
  void parse () { cout << test(&WVObject::evalA); }
                                          ^
prog.cpp:27:47: error: no matching function for call to ‘WVKnoten::test(bool (WVObject::*)(long unsigned int)const)’
  void parse () { cout << test(&WVObject::evalA); }
                                               ^
prog.cpp:27:47: note: candidate is:
prog.cpp:12:10: note: bool WVObject::test(WVObject::EvalFun) const
     bool test (EvalFun fnctToEval) const
          ^
prog.cpp:12:10: note:   no known conversion for argument 1 from ‘bool (WVObject::*)(long unsigned int)const’ to ‘WVObject::EvalFun {aka bool (*)(long unsigned int)}’

Standard output is empty