c++98 enums

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>


typedef std::vector<std::string> EString;
template<class T>
struct Enum {
	template<typename EType>
	static std::string toString(EType etype) {
		if ((etype < 0) || (etype > T::eString().size())) {
			return "INVALID_ENUM";
		}
		return T::eString()[static_cast<int>(etype)];
	}

	static typename T::eType toEnum(std::string str) {
		int res = - 1;
		EString strings = T::eString();
		EString::iterator it = std::find(strings.begin(), strings.end(), str);
		if (it != strings.end())
			res = std::distance(strings.begin(), it);
		return static_cast<typename T::eType>(res);
	}
	
};

struct EStringInitializer {
	EStringInitializer(const std::string& first){
		strings.push_back(first);
	}
	
	EStringInitializer& operator () (const std::string& value) {
		strings.push_back(value);
		return *this;
	}
	
	operator EString() {
		return strings;
	}
		EString strings;	
};


struct MyEnum {
	enum eType {ZERO, ONE, TWO};
	static EString eString () {
		return EStringInitializer("ZERO")("ONE")("TWO");
	}

};


int main() {
	MyEnum::eType zero = MyEnum::ZERO;
	std::cout << zero <<  " -> " << Enum<MyEnum>::toString(zero) << std::endl;

	std::string one_str = "ONE";
	MyEnum::eType one = Enum<MyEnum>::toEnum("ONE");
	std::cout << one_str << " -> "  << one <<  " -> " << Enum<MyEnum>::toString(one) << std::endl;

	MyEnum::eType invalid1 = static_cast<MyEnum::eType>(-1);
	std::cout << invalid1  <<  " -> " << Enum<MyEnum>::toString(invalid1) << std::endl;

	MyEnum::eType invalid2 = static_cast<MyEnum::eType>(555);
	std::cout << invalid2  <<  " -> " << Enum<MyEnum>::toString(invalid2) << std::endl;

	std::string invalid_str = "Some invalid value";
	MyEnum::eType invalid3 = Enum<MyEnum>::toEnum(invalid_str);
	std::cout << invalid_str <<   " -> " << invalid3  <<  " -> " << Enum<MyEnum>::toString(invalid3) << std::endl;


	return 0;
}

➜  /tmp  g++ ./enum.cpp -std=c++98 -pedantic && ./a.out  
0 -> ZERO
ONE -> 1 -> ONE
-1 -> INVALID_ENUM
555 -> INVALID_ENUM
Some invalid value -> -1 -> INVALID_ENUM