#include <vector>
#include <algorithm>
#include <functional>
#include <string>
#include <iostream>
using namespace std;
using std::placeholders::_1;

int main() {
	std::string v1 = "foo";
	std::string v2 = "foo";
	
	bool r = 
	    std::bind(
	        static_cast<bool(*)(const std::string&, const std::string&)>(&std::operator==<char, std::string::traits_type, std::string::allocator_type>),
	        std::placeholders::_1,
	        std::cref(v1))(v2);
	return 0;
}