Any one line solution to copy a golang map

Why don’t you make a struct receiver containing this map (do not export the map) and a lookup or getter (read-only) method on it? Something like this:

type MyMap struct {
	myHugeMap map[string]string
}

func (m *MyMap) get(i string) (string, error) {
	e, ok := m[i]
	if !ok {
		return "", fmt.Errorf("element %s not found", i)
	}
	return e, nil
}

Of course, this should be in a separate package and you should pass around pointer to this struct.