addDays :: Integer -> Day -> Day
diffDays :: Day -> Day -> Integer
fromGregorian :: Integer -> Int -> Int -> Day
convert from proleptic Gregorian calendar. First argument is year, second month number (1-12), third day (1-31). Invalid values will be clipped to the correct range, month first, then day.
getCurrentTime :: IO UTCTime
The Data.Time
module from time
package provides support for retrieving & manipulating date & time values: