27 Time library [time]

27.5 Class template duration [time.duration]

27.5.3 Arithmetic [time.duration.arithmetic]

constexpr common_type_t<duration> operator+() const;
Returns: common_­type_­t<duration>(*this).
constexpr common_type_t<duration> operator-() const;
Returns: common_­type_­t<duration>(-rep_­).
constexpr duration& operator++();
Effects: As if by ++rep_­.
Returns: *this.
constexpr duration operator++(int);
Returns: duration(rep_­++).
constexpr duration& operator--();
Effects: As if by --rep_­.
Returns: *this.
constexpr duration operator--(int);
Returns: duration(rep_­--).
constexpr duration& operator+=(const duration& d);
Effects: As if by: rep_­ += d.count();
Returns: *this.
constexpr duration& operator-=(const duration& d);
Effects: As if by: rep_­ -= d.count();
Returns: *this.
constexpr duration& operator*=(const rep& rhs);
Effects: As if by: rep_­ *= rhs;
Returns: *this.
constexpr duration& operator/=(const rep& rhs);
Effects: As if by: rep_­ /= rhs;
Returns: *this.
constexpr duration& operator%=(const rep& rhs);
Effects: As if by: rep_­ %= rhs;
Returns: *this.
constexpr duration& operator%=(const duration& rhs);
Effects: As if by: rep_­ %= rhs.count();
Returns: *this.