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#include <iostream>
using namespace std;
 
template<class This, class Ret, class... Args>
void CallMe(This* aThis, Ret(This::*aMethod)(Args...), Args... aArgs)
{
	// Should not use std::forward without universal reference.
	(aThis->*aMethod)(std::forward<Args>(aArgs)...);
}
 
 
template<class This, class Ret, class... Args, class... ActualArgs>
void CallMe2(This* aThis, Ret(This::*aMethod)(Args...), ActualArgs&&... aArgs)
{
	(aThis->*aMethod)(std::forward<ActualArgs>(aArgs)...);
}
 
class Foo
{
public:
	Foo() {}
	Foo(const Foo&) { cout << "copy" << endl; }
	Foo(Foo&&) { cout << "move" << endl; }
};
 
class Bar
{
public:
	void Call(Foo& aFoo) { cout << "Invoke" << endl; }
};
int main() {
	Bar b;
	Foo f;
	//Will lead to a deduction ambiguity.
	CallMe(&b, &Bar::Call, f);
	//This version can fix the problem.
	//CallMe2(&b, &Bar::Call, f);
	return 0;
}

prog.cpp: In function 'int main()':
prog.cpp:35:26: error: no matching function for call to 'CallMe(Bar*, void (Bar::*)(Foo&), Foo&)'
  CallMe(&b, &Bar::Call, f);
                          ^
prog.cpp:5:6: note: candidate: template<class This, class Ret, class ... Args> void CallMe(This*, Ret (This::*)(Args ...), Args ...)
 void CallMe(This* aThis, Ret(This::*aMethod)(Args...), Args... aArgs)
      ^
prog.cpp:5:6: note:   template argument deduction/substitution failed:
prog.cpp:35:26: note:   inconsistent parameter pack deduction with 'Foo&' and 'Foo'
  CallMe(&b, &Bar::Call, f);
                          ^

Standard output is empty