Data.Time.ZoneInfo

Provides access to the Olson zone-info database, using an adapted version of the Olson zone-info library.

Documentation

type Olson = ForeignPtr COlson

type ZoneInfo = (Olson, Ptr CZoneInfo)

A ZoneInfo object's lifetime is bound to its Olson parent. The pair includes the Olson parent to ensure that it is not garbage collected while the ZoneInfo object is still in use.

newOlson :: Maybe String -> IO Olson

Create a new Olson context object. A path to the zone-info database may be specified. Otherwise, the TZDIR environment variable, or a reasonable default, will be used. An IOError will be thrown on failure.

getZoneInfo :: Olson -> String -> IO ZoneInfo

Obtain a ZoneInfo object based on the specified Olson identifier or time-zone. If the zone-info database cannot be found, or the time-zone not recognised, then an IOError will be thrown. Calls to this function must be serialised across multiple threads.

utcZoneInfo :: Olson -> ZoneInfo

ZoneInfo for the UTC time-zone.

getZoneName :: ZoneInfo -> Bool -> IO String

Returns the zone-name for either the standard or daylight saving zone, depending on the isdst argument.

getZoneMinutes :: ZoneInfo -> Bool -> IO Int

Returns the UTC offset for either the standard or daylight saving zone, depending on the isdst argument.

posixToZonedTime :: ZoneInfo -> POSIXTime -> IO ZonedTime

Convert from POSIXTime to zoned LocalTime.

utcToZonedTime' :: ZoneInfo -> UTCTime -> IO ZonedTime

Convert from UTCTime to zoned LocalTime.

localToPOSIXZoned :: ZoneInfo -> LocalTime -> IO (POSIXTime, ZonedTime)

Convert LocalTime to a daylight saving adjusted pair.

localToUTCZoned :: ZoneInfo -> LocalTime -> IO (UTCTime, ZonedTime)

Convert LocalTime to a daylight saving adjusted pair.

convertTimeZone :: ZoneInfo -> LocalTime -> ZoneInfo -> IO ZonedTime

Convert the LocalTime argument from the source to destination TimeZone.