Data.Time.Clock

time-1.8.0.2: A time library

Safe Haskell | Safe
Language | Haskell2010

Data.Time.Clock

Contents

- Universal Time
- Absolute intervals
- UTC

Description

Types and functions for UTC and UT1

Synopsis

- newtype UniversalTime = ModJulianDate {
  - getModJulianDate :: Rational
  }
- data DiffTime
- secondsToDiffTime :: Integer -> DiffTime
- picosecondsToDiffTime :: Integer -> DiffTime
- diffTimeToPicoseconds :: DiffTime -> Integer
- data UTCTime = UTCTime {
  - utctDay :: Day
  - utctDayTime :: DiffTime
  }
- data NominalDiffTime
- nominalDay :: NominalDiffTime
- addUTCTime :: NominalDiffTime -> UTCTime -> UTCTime
- diffUTCTime :: UTCTime -> UTCTime -> NominalDiffTime
- getCurrentTime :: IO UTCTime
- getTime_resolution :: DiffTime

# Universal Time

Time as measured by the Earth.

newtype UniversalTime Source #

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.

Constructors

ModJulianDate |
Fields getModJulianDate :: Rational

Instances

Eq UniversalTime # |
Methods (==) :: UniversalTime -> UniversalTime -> Bool # (/=) :: UniversalTime -> UniversalTime -> Bool #
Data UniversalTime # |
Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> UniversalTime -> c UniversalTime Source # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c UniversalTime Source # toConstr :: UniversalTime -> Constr Source # dataTypeOf :: UniversalTime -> DataType Source # dataCast1 :: Typeable (* -> *) t => (forall d. Data d => c (t d)) -> Maybe (c UniversalTime) Source # dataCast2 :: Typeable (* -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c UniversalTime) Source # gmapT :: (forall b. Data b => b -> b) -> UniversalTime -> UniversalTime Source # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> UniversalTime -> r Source # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> UniversalTime -> r Source # gmapQ :: (forall d. Data d => d -> u) -> UniversalTime -> [u] Source # gmapQi :: Int -> (forall d. Data d => d -> u) -> UniversalTime -> u Source # gmapM :: Monad m => (forall d. Data d => d -> m d) -> UniversalTime -> m UniversalTime Source # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> UniversalTime -> m UniversalTime Source # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> UniversalTime -> m UniversalTime Source #
Ord UniversalTime # |
Methods compare :: UniversalTime -> UniversalTime -> Ordering # (<) :: UniversalTime -> UniversalTime -> Bool # (<=) :: UniversalTime -> UniversalTime -> Bool # (>) :: UniversalTime -> UniversalTime -> Bool # (>=) :: UniversalTime -> UniversalTime -> Bool # max :: UniversalTime -> UniversalTime -> UniversalTime # min :: UniversalTime -> UniversalTime -> UniversalTime #
NFData UniversalTime # |
Methods rnf :: UniversalTime -> () Source #
ParseTime UniversalTime # |
Methods buildTime :: TimeLocale -> [(Char, String)] -> Maybe UniversalTime Source #
FormatTime UniversalTime # |
Methods formatCharacter :: Char -> Maybe (TimeLocale -> Maybe NumericPadOption -> Maybe Int -> UniversalTime -> String) Source #

# Absolute intervals

data DiffTime Source #

This is a length of time, as measured by a clock. Conversion functions will treat it as seconds. It has a precision of 10^-12 s.

Instances

Enum DiffTime # |
Methods succ :: DiffTime -> DiffTime Source # pred :: DiffTime -> DiffTime Source # toEnum :: Int -> DiffTime Source # fromEnum :: DiffTime -> Int Source # enumFrom :: DiffTime -> [DiffTime] Source # enumFromThen :: DiffTime -> DiffTime -> [DiffTime] Source # enumFromTo :: DiffTime -> DiffTime -> [DiffTime] Source # enumFromThenTo :: DiffTime -> DiffTime -> DiffTime -> [DiffTime] Source #
Eq DiffTime # |
Methods (==) :: DiffTime -> DiffTime -> Bool # (/=) :: DiffTime -> DiffTime -> Bool #
Fractional DiffTime # |
Methods (/) :: DiffTime -> DiffTime -> DiffTime Source # recip :: DiffTime -> DiffTime Source # fromRational :: Rational -> DiffTime Source #
Data DiffTime # |
Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> DiffTime -> c DiffTime Source # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c DiffTime Source # toConstr :: DiffTime -> Constr Source # dataTypeOf :: DiffTime -> DataType Source # dataCast1 :: Typeable (* -> *) t => (forall d. Data d => c (t d)) -> Maybe (c DiffTime) Source # dataCast2 :: Typeable (* -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c DiffTime) Source # gmapT :: (forall b. Data b => b -> b) -> DiffTime -> DiffTime Source # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> DiffTime -> r Source # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> DiffTime -> r Source # gmapQ :: (forall d. Data d => d -> u) -> DiffTime -> [u] Source # gmapQi :: Int -> (forall d. Data d => d -> u) -> DiffTime -> u Source # gmapM :: Monad m => (forall d. Data d => d -> m d) -> DiffTime -> m DiffTime Source # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> DiffTime -> m DiffTime Source # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> DiffTime -> m DiffTime Source #
Num DiffTime # |
Methods (+) :: DiffTime -> DiffTime -> DiffTime Source # (-) :: DiffTime -> DiffTime -> DiffTime Source # (*) :: DiffTime -> DiffTime -> DiffTime Source # negate :: DiffTime -> DiffTime Source # abs :: DiffTime -> DiffTime Source # signum :: DiffTime -> DiffTime Source # fromInteger :: Integer -> DiffTime Source #
Ord DiffTime # |
Methods compare :: DiffTime -> DiffTime -> Ordering # (<) :: DiffTime -> DiffTime -> Bool # (<=) :: DiffTime -> DiffTime -> Bool # (>) :: DiffTime -> DiffTime -> Bool # (>=) :: DiffTime -> DiffTime -> Bool # max :: DiffTime -> DiffTime -> DiffTime # min :: DiffTime -> DiffTime -> DiffTime #
Real DiffTime # |
Methods toRational :: DiffTime -> Rational Source #
RealFrac DiffTime # |
Methods properFraction :: Integral b => DiffTime -> (b, DiffTime) Source # truncate :: Integral b => DiffTime -> b Source # round :: Integral b => DiffTime -> b Source # ceiling :: Integral b => DiffTime -> b Source # floor :: Integral b => DiffTime -> b Source #
Show DiffTime # |
Methods showsPrec :: Int -> DiffTime -> ShowS Source # show :: DiffTime -> String Source # showList :: [DiffTime] -> ShowS Source #
NFData DiffTime # |
Methods rnf :: DiffTime -> () Source #

secondsToDiffTime :: Integer -> DiffTime Source #

Create a `DiffTime` which represents an integral number of seconds.

picosecondsToDiffTime :: Integer -> DiffTime Source #

Create a `DiffTime` from a number of picoseconds.

diffTimeToPicoseconds :: DiffTime -> Integer Source #

Get the number of picoseconds in a `DiffTime`.

# UTC

UTC is time as measured by a clock, corrected to keep pace with the earth by adding or removing occasional seconds, known as "leap seconds". These corrections are not predictable and are announced with six month's notice. No table of these corrections is provided, as any program compiled with it would become out of date in six months.

If you don't care about leap seconds, use `UTCTime` and `NominalDiffTime` for your clock calculations, and you'll be fine.

data UTCTime Source #

This is the simplest representation of UTC. It consists of the day number, and a time offset from midnight. Note that if a day has a leap second added to it, it will have 86401 seconds.

Constructors

UTCTime |
Fields utctDay :: Day the day utctDayTime :: DiffTime the time from midnight, 0 <= t < 86401s (because of leap-seconds)

Instances

Eq UTCTime # |
Methods (==) :: UTCTime -> UTCTime -> Bool # (/=) :: UTCTime -> UTCTime -> Bool #
Data UTCTime # |
Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> UTCTime -> c UTCTime Source # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c UTCTime Source # toConstr :: UTCTime -> Constr Source # dataTypeOf :: UTCTime -> DataType Source # dataCast1 :: Typeable (* -> *) t => (forall d. Data d => c (t d)) -> Maybe (c UTCTime) Source # dataCast2 :: Typeable (* -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c UTCTime) Source # gmapT :: (forall b. Data b => b -> b) -> UTCTime -> UTCTime Source # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> UTCTime -> r Source # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> UTCTime -> r Source # gmapQ :: (forall d. Data d => d -> u) -> UTCTime -> [u] Source # gmapQi :: Int -> (forall d. Data d => d -> u) -> UTCTime -> u Source # gmapM :: Monad m => (forall d. Data d => d -> m d) -> UTCTime -> m UTCTime Source # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> UTCTime -> m UTCTime Source # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> UTCTime -> m UTCTime Source #
Ord UTCTime # |
Methods compare :: UTCTime -> UTCTime -> Ordering # (<) :: UTCTime -> UTCTime -> Bool # (<=) :: UTCTime -> UTCTime -> Bool # (>) :: UTCTime -> UTCTime -> Bool # (>=) :: UTCTime -> UTCTime -> Bool # max :: UTCTime -> UTCTime -> UTCTime # min :: UTCTime -> UTCTime -> UTCTime #
NFData UTCTime # |
Methods rnf :: UTCTime -> () Source #
ParseTime UTCTime # |
Methods buildTime :: TimeLocale -> [(Char, String)] -> Maybe UTCTime Source #
FormatTime UTCTime # |
Methods formatCharacter :: Char -> Maybe (TimeLocale -> Maybe NumericPadOption -> Maybe Int -> UTCTime -> String) Source #

data NominalDiffTime Source #

This is a length of time, as measured by UTC. Conversion functions will treat it as seconds. It has a precision of 10^-12 s. It ignores leap-seconds, so it's not necessarily a fixed amount of clock time. For instance, 23:00 UTC + 2 hours of NominalDiffTime = 01:00 UTC (+ 1 day), regardless of whether a leap-second intervened.

Instances

Enum NominalDiffTime # |
Methods succ :: NominalDiffTime -> NominalDiffTime Source # pred :: NominalDiffTime -> NominalDiffTime Source # toEnum :: Int -> NominalDiffTime Source # fromEnum :: NominalDiffTime -> Int Source # enumFrom :: NominalDiffTime -> [NominalDiffTime] Source # enumFromThen :: NominalDiffTime -> NominalDiffTime -> [NominalDiffTime] Source # enumFromTo :: NominalDiffTime -> NominalDiffTime -> [NominalDiffTime] Source # enumFromThenTo :: NominalDiffTime -> NominalDiffTime -> NominalDiffTime -> [NominalDiffTime] Source #
Eq NominalDiffTime # |
Methods (==) :: NominalDiffTime -> NominalDiffTime -> Bool # (/=) :: NominalDiffTime -> NominalDiffTime -> Bool #
Fractional NominalDiffTime # |
Methods (/) :: NominalDiffTime -> NominalDiffTime -> NominalDiffTime Source # recip :: NominalDiffTime -> NominalDiffTime Source # fromRational :: Rational -> NominalDiffTime Source #
Data NominalDiffTime # |
Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> NominalDiffTime -> c NominalDiffTime Source # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c NominalDiffTime Source # toConstr :: NominalDiffTime -> Constr Source # dataTypeOf :: NominalDiffTime -> DataType Source # dataCast1 :: Typeable (* -> *) t => (forall d. Data d => c (t d)) -> Maybe (c NominalDiffTime) Source # dataCast2 :: Typeable (* -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c NominalDiffTime) Source # gmapT :: (forall b. Data b => b -> b) -> NominalDiffTime -> NominalDiffTime Source # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> NominalDiffTime -> r Source # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> NominalDiffTime -> r Source # gmapQ :: (forall d. Data d => d -> u) -> NominalDiffTime -> [u] Source # gmapQi :: Int -> (forall d. Data d => d -> u) -> NominalDiffTime -> u Source # gmapM :: Monad m => (forall d. Data d => d -> m d) -> NominalDiffTime -> m NominalDiffTime Source # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> NominalDiffTime -> m NominalDiffTime Source # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> NominalDiffTime -> m NominalDiffTime Source #
Num NominalDiffTime # |
Methods (+) :: NominalDiffTime -> NominalDiffTime -> NominalDiffTime Source # (-) :: NominalDiffTime -> NominalDiffTime -> NominalDiffTime Source # (*) :: NominalDiffTime -> NominalDiffTime -> NominalDiffTime Source # negate :: NominalDiffTime -> NominalDiffTime Source # abs :: NominalDiffTime -> NominalDiffTime Source # signum :: NominalDiffTime -> NominalDiffTime Source # fromInteger :: Integer -> NominalDiffTime Source #
Ord NominalDiffTime # |
Methods compare :: NominalDiffTime -> NominalDiffTime -> Ordering # (<) :: NominalDiffTime -> NominalDiffTime -> Bool # (<=) :: NominalDiffTime -> NominalDiffTime -> Bool # (>) :: NominalDiffTime -> NominalDiffTime -> Bool # (>=) :: NominalDiffTime -> NominalDiffTime -> Bool # max :: NominalDiffTime -> NominalDiffTime -> NominalDiffTime # min :: NominalDiffTime -> NominalDiffTime -> NominalDiffTime #
Real NominalDiffTime # |
Methods toRational :: NominalDiffTime -> Rational Source #
RealFrac NominalDiffTime # |
Methods properFraction :: Integral b => NominalDiffTime -> (b, NominalDiffTime) Source # truncate :: Integral b => NominalDiffTime -> b Source # round :: Integral b => NominalDiffTime -> b Source # ceiling :: Integral b => NominalDiffTime -> b Source # floor :: Integral b => NominalDiffTime -> b Source #
Show NominalDiffTime # |
Methods showsPrec :: Int -> NominalDiffTime -> ShowS Source # show :: NominalDiffTime -> String Source # showList :: [NominalDiffTime] -> ShowS Source #
NFData NominalDiffTime # |
Methods rnf :: NominalDiffTime -> () Source #

nominalDay :: NominalDiffTime Source #

One day in `NominalDiffTime`.

addUTCTime :: NominalDiffTime -> UTCTime -> UTCTime Source #

addUTCTime a b = a + b

diffUTCTime :: UTCTime -> UTCTime -> NominalDiffTime Source #

diffUTCTime a b = a - b

getCurrentTime :: IO UTCTime Source #

Get the current `UTCTime` from the system clock.

getTime_resolution :: DiffTime Source #

The resolution of `getSystemTime`, `getCurrentTime`, `getPOSIXTime`