Hiva::Rate类型定义

namespace Hiva {
/* Class to help run loops at a desired frequency */
class BaseRate {
public:
    BaseRate(const double frequency);
    explicit BaseRate(const BaseDuration &durationVal);
    virtual ~BaseRate() = default;
    virtual bool Sleep() = 0;
    virtual void Reset() = 0;
    BaseDuration CycleTime() const;
    BaseDuration ExpectedCycleTime() const;
protected:
    BaseDuration expectedCycleTime_;
    BaseDuration actualCycleTime_;
};
}

namespace Hiva {
/* Class to help run loops at a desired frequency */
class HivaRate : public BaseRate {
public:
    HivaRate(const double frequency);
    explicit HivaRate(const BaseDuration &durationVal);
    ~HivaRate() override = default;
    bool Sleep() override;
    void Reset() override;
private:
    HivaTime start_;
};
} 

namespace Hiva {
/* Class to help run loops at a desired frequency */
class WallRate : public BaseRate {
public:
    WallRate(const double frequency);
    explicit WallRate(const BaseDuration &durationVal);
    ~WallRate() override = default;
    bool Sleep() override;
    void Reset() override;
private:
    WallTime start_;
};
}