ref_count.hpp

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#ifndef UTILS_REF_COUNT_H_0FC2C86B_8E95_45EF_AADE_F0A5C4ECBC31
#define UTILS_REF_COUNT_H_0FC2C86B_8E95_45EF_AADE_F0A5C4ECBC31
 
#include <optional>
 
template<typename T> struct ref_count_init_once {
        std::optional<T> operator()(T (*init)(void), int &i) {
                if (i++ == 0) {
                        return std::optional<T>(init());
                }
                return std::nullopt;
        }
};
 
struct ref_count_terminate_last {
        void operator()(void (*terminate)(void), int &i) {
                if (--i == 0) {
                        terminate();
                }
        }
};
 
#endif // defined UTILS_REF_COUNT_H_0FC2C86B_8E95_45EF_AADE_F0A5C4ECBC31