29 Time library [time]

29.5 Class template duration [time.duration]

29.5.5 Special values [time.duration.special]

static constexpr duration zero() noexcept;
Returns: duration(duration_­values<rep>​::​zero()).
static constexpr duration min() noexcept;
Returns: duration(duration_­values<rep>​::​min()).
static constexpr duration max() noexcept;
Returns: duration(duration_­values<rep>​::​max()).