gistfile1.cpp

#include <iostream>
#include <string>

template <typename T, typename T_Infix>
struct InfixProxy {
	T const & lhs_;
	T_Infix const & oper_;

	InfixProxy(T const & lhs, T_Infix const & oper)
		: lhs_(lhs), oper_(oper)
	{}

	friend T operator>>(const InfixProxy<T, T_Infix>& self, T const & rhs)
	{
		return self.oper_(self.lhs_, rhs);
	}
};

struct Infix {
	template <typename T, typename T_Infix>
	friend InfixProxy<T, T_Infix> operator<<(T const & lhs, T_Infix const & rhs)
	{
		return InfixProxy<T, T_Infix>(lhs, rhs);
	}
};


struct Add : public Infix
{
	template <typename T>
	T operator()(T const & lhs, T const & rhs) const
	{
		return lhs + rhs;
	}
} add;

int main()
{
	int a = 2, b = 3;

	std::cout << (a <<add>> b) << std::endl;

	std::string x = "foo", y = "bar";

	std::cout << (x <<add>> y) << std::endl;


}