DateTime

assert(TimeSpan.zero > TimeSpan.min);
assert(TimeSpan.max  > TimeSpan.zero);
assert(TimeSpan.max  > TimeSpan.min);
assert(TimeSpan.zero >= TimeSpan.zero);
assert(TimeSpan.zero <= TimeSpan.zero);
assert(TimeSpan.max >= TimeSpan.max);
assert(TimeSpan.max <= TimeSpan.max);
assert(TimeSpan.min >= TimeSpan.min);
assert(TimeSpan.min <= TimeSpan.min);

assert (TimeSpan.fromSeconds(50).seconds is 50);
assert (TimeSpan.fromSeconds(5000).seconds is 5000);
assert (TimeSpan.fromMinutes(50).minutes is 50);
assert (TimeSpan.fromMinutes(5000).minutes is 5000);
assert (TimeSpan.fromHours(23).hours is 23);
assert (TimeSpan.fromHours(5000).hours is 5000);
assert (TimeSpan.fromDays(6).days is 6);
assert (TimeSpan.fromDays(5000).days is 5000);

assert (TimeSpan.fromSeconds(50).time.seconds is 50);
assert (TimeSpan.fromSeconds(5000).time.seconds is 5000 % 60);
assert (TimeSpan.fromMinutes(50).time.minutes is 50);
assert (TimeSpan.fromMinutes(5000).time.minutes is 5000 % 60);
assert (TimeSpan.fromHours(23).time.hours is 23);
assert (TimeSpan.fromHours(5000).time.hours is 5000 % 24);

auto ts = TimeSpan.fromHours(20);
assert (TimeSpan.fromHours(10) + TimeSpan.fromHours(10) == ts);
assert (TimeSpan.fromHours(30) - TimeSpan.fromHours(10) == ts);
auto ts2 = TimeSpan.fromHours(10);
ts2 += TimeSpan.fromHours(10);
assert(ts2 == ts);

auto tod = TimeOfDay (25, 2, 3, 4);
tod = tod.span.time;
assert (tod.hours is 1);
assert (tod.minutes is 2);
assert (tod.seconds is 3);
assert (tod.millis is 4);