default_delete<*fstream>.cc

namespace std {
    template <>
    struct default_delete<fstream> {
        void operator()(fstream *ptr) {
            if (ptr != nullptr && ptr->is_open()) {
                ptr->close();
            }

            delete ptr;
        }
    };
    
    template <>
    struct default_delete<ifstream> {
        void operator()(ifstream *ptr) {
            if (ptr != nullptr && ptr->is_open()) {
                ptr->close();
            }

            delete ptr;
        }
    };
    
    template <>
    struct default_delete<ofstream> {
        void operator()(ofstream *ptr) {
            if (ptr != nullptr && ptr->is_open()) {
                ptr->close();
            }

            delete ptr;
        }
    };
}