初始化private static const map in C++

#include <map>
using namespace std;

struct A{
static map<int,int> create_map()
{
map<int,int> m;
m[1] = 2;
m[3] = 4;
m[5] = 6;
return m;
}
static const map<int,int> myMap;

};

const map<int,int> A:: myMap =  A::create_map();

int main() {
}

出自：http://stackoverflow.com/questions/2636303/how-to-initialize-a-private-static-const-map-in-c