int64_t operator-(int64_t& lhs, int64_t& rhs)
int64_t operator-(int64_t& lhs, float& rhs) //not likely but still valid in some universe
int64_t operator-(int64_t& lhs, int& rhs)
int64_t operator-(int64_t& lhs, NSInteger& rhs) //probably not going to happen, as NSInteger is too much like NSNumeric, even if one is typecast and one is an object