verify() (answer: Bool) pure {
 value = dever.time.parseDatetime("2024-02-29T12:34:56.12+08:00")
 formatted = dever.time.formatDatetime(value)
 date = dever.time.formatDate(dever.time.parseDate("2024-02-29"))
 clock = dever.time.formatTime(dever.time.parseTime("12:34:56.000"))
 epoch = dever.time.parseDatetime("1970-01-01T00:00:00Z")
 span = dever.time.duration(1)
 later = dever.time.add(epoch, span)
 earlier = dever.time.subtract(epoch, span)
 answer = formatted == "2024-02-29T04:34:56.120Z" and date == "2024-02-29" and clock == "12:34:56" and dever.time.difference(later, epoch) == span and dever.time.formatDatetime(earlier) == "1969-12-31T23:59:59.999Z"
}

clocks() (answer: Bool) {
 current = dever.time.now()
 round_trip = dever.time.parseDatetime(dever.time.formatDatetime(current))
 unix = dever.time.unixMillis()
 first = dever.time.monotonicNanos()
 second = dever.time.monotonicNanos()
 answer = current == round_trip and unix > 0 and second >= first
}

invalid() (value: Date) { value = dever.time.parseDate("2023-02-29") }