instance Show UniversalTime

lib/Data/Time/Clock/Scale.hs

@@ -23,6 +23,9 @@ import Data.Data
 
 -- | The Modified Julian Date is the day with the fraction of the day, measured from UT midnight.
 -- It's used to represent UT1, which is time as measured by the earth's rotation, adjusted for various wobbles.
+--
+-- For the 'Show' instance of 'UniversalTime',
+-- import "Data.Time" or "Data.Time.LocalTime".
 newtype UniversalTime = ModJulianDate {getModJulianDate :: Rational} deriving (Eq,Ord
 #if LANGUAGE_DeriveDataTypeable
 #if LANGUAGE_Rank2Types

lib/Data/Time/LocalTime/LocalTime.hs

@@ -70,6 +70,10 @@ ut1ToLocalTime long (ModJulianDate date) = LocalTime (ModifiedJulianDay localMJD
 localTimeToUT1 :: Rational -> LocalTime -> UniversalTime
 localTimeToUT1 long (LocalTime (ModifiedJulianDay localMJD) tod) = ModJulianDate ((fromIntegral localMJD) + (timeOfDayToDayFraction tod) - (long / 360))
 
+-- orphan instance
+instance Show UniversalTime where
+    show t = show (ut1ToLocalTime 0 t)
+
 -- | A local time together with a TimeZone.
 --
 -- For the 'Read' instance of 'ZonedTime',