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#include <iostream>
#include <array>
 
using namespace std;
 
typedef size_t Data;
 
class MyFunction
{
private:
	static const std::array<std::string, 3> values;
public:
	template<size_t N>
	static void Func(const Data& aData)
	{
		size_t index = (N > aData ? 2 : (N == aData ? 1 : 0) );
		cout << "Function::Func<"<< N << ">:\t" << N << values[index] << aData << endl;
	}
 
	typedef decltype(&Func<0>) type;	
};
 
const std::array<std::string, 3> MyFunction::values {"<", "=", ">"};
 
template<class Function, size_t N>
class FunctionManager
{
private:
	static const typename Function::type func_;
 
	static constexpr typename Function::type Create()
	{
		return &Function::Func<N>;
	}
public:	
	void operator()(const Data &aData) const
	{
		func_(aData);
	}
};
 
template<class Function, size_t N>
const typename Function::type FunctionManager<Function, N>::func_ = FunctionManager<Function, N>::Create();
 
int main()
{
	static const size_t N = 6;
	auto man = FunctionManager<MyFunction, N>();
	man(N/2);
	return 0;
}

prog.cpp: In static member function ‘static constexpr typename Function::type FunctionManager<Function, N>::Create()’:
prog.cpp:33:28: error: expected primary-expression before ‘;’ token
   return &Function::Func<N>;
                            ^
prog.cpp: In instantiation of ‘static constexpr typename Function::type FunctionManager<Function, N>::Create() [with Function = MyFunction; unsigned int N = 6u; typename Function::type = void (*)(const unsigned int&)]’:
prog.cpp:43:106:   required from ‘void (* const FunctionManager<MyFunction, 6u>::func_)(const Data&)’
prog.cpp:38:14:   required from ‘void FunctionManager<Function, N>::operator()(const Data&) const [with Function = MyFunction; unsigned int N = 6u; Data = unsigned int]’
prog.cpp:49:9:   required from here
prog.cpp:33:25: error: address of overloaded function with no contextual type information
   return &Function::Func<N>;
                         ^
prog.cpp:34:2: error: body of constexpr function ‘static constexpr typename Function::type FunctionManager<Function, N>::Create() [with Function = MyFunction; unsigned int N = 6u; typename Function::type = void (*)(const unsigned int&)]’ not a return-statement
  }
  ^
prog.cpp: In static member function ‘static constexpr typename Function::type FunctionManager<Function, N>::Create() [with Function = MyFunction; unsigned int N = 6u; typename Function::type = void (*)(const unsigned int&)]’:
prog.cpp:34:2: warning: control reaches end of non-void function [-Wreturn-type]
  }
  ^

Standard output is empty