p7/Timestamp.hs
2018-07-02 10:41:33 +12:00

25 lines
648 B
Haskell

module Timestamp where
data Timestamp = Ts Integer Integer Integer deriving Show
isPreviewSeason :: Timestamp -> Bool
isPreviewSeason (Ts x _ _) = x >= 20
inFuture :: Timestamp -> Timestamp -> Bool
inFuture (Ts d1 m1 y1) (Ts d2 m2 y2)
| y1 /= y2 = y1 > y2
| m1 /= m2 = m1 > m2
| d1 /= d2 = d1 > d2
| otherwise = False
monthsSince :: Timestamp -> Timestamp -> Integer
monthsSince (Ts d1 m1 y1) (Ts d2 m2 y2)
| t1 `inFuture` t2 = (12 * (y1 - y2)) + (m1 - m2)
| otherwise = 0
where
t1 = Ts d1 m1 y1
t2 = Ts d2 m2 y2
toTS :: (Integer, Integer, Integer) -> Timestamp
toTS (y,m,d) = Ts d m y