@code{cpp}
template<class T>
class Result {
- enum class ResultStatus {
- invalid,
- value,
- exception,
- };
public:
- Result();
- ~Result();
- Result(Result const& that);
- Result& operator=(Result const& that);
- Result(Result&& that);
- Result& operator=(Result&& that);
bool is_valid() const;
- void reset();
void set_exception(std::exception_ptr e);
void set_value(T&& value);
void set_value(T const& value);
T get();
private:
- ResultStatus status_ = ResultStatus::invalid;
- union {
- T value_;
- std::exception_ptr exception_;
- };
+ boost::variant<boost::blank, T, std::exception_ptr> value_;
};
@endcode~
