-- Stability : provisional
-- Portability : portable
--
--- The standard Time library.
---
+-- The standard Time library, providing standard functionality for clock
+-- times, including timezone information (i.e, the functionality of
+-- \"@time.h@\", adapted to the Haskell environment). It follows RFC
+-- 1129 in its use of Coordinated Universal Time (UTC).
-----------------------------------------------------------------------------
{-
Haskell 98 Time of Day Library
------------------------------
-The Time library provides standard functionality for clock times,
-including timezone information (i.e, the functionality of "time.h",
-adapted to the Haskell environment), It follows RFC 1129 in its use of
-Coordinated Universal Time (UTC).
-
2000/06/17 <michael.weber@post.rwth-aachen.de>:
RESTRICTIONS:
* min./max. time diff currently is restricted to
module System.Time
(
- Month(..)
- , Day(..)
+ -- * Clock times
- , ClockTime(..) -- non-standard, lib. report gives this as abstract
+ ClockTime(..) -- non-standard, lib. report gives this as abstract
-- instance Eq, Ord
-- instance Show (non-standard)
, getClockTime
+ -- * Time differences
+
, TimeDiff(..)
, noTimeDiff -- non-standard (but useful when constructing TimeDiff vals.)
, diffClockTimes
, timeDiffToString -- non-standard
, formatTimeDiff -- non-standard
+ -- * Calendar times
+
, CalendarTime(..)
+ , Month(..)
+ , Day(..)
, toCalendarTime
, toUTCTime
, toClockTime
#ifdef __NHC__
#include <time.h>
-# ifdef __sun
+# if defined(__sun) || defined(__CYGWIN32__)
# define HAVE_TZNAME 1
# else
# define HAVE_TM_ZONE 1
-- One way to partition and give name to chunks of a year and a week:
+-- | A month of the year.
+
data Month
= January | February | March | April
| May | June | July | August
| September | October | November | December
deriving (Eq, Ord, Enum, Bounded, Ix, Read, Show)
+-- | A day of the week.
+
data Day
= Sunday | Monday | Tuesday | Wednesday
| Thursday | Friday | Saturday
deriving (Eq, Ord, Enum, Bounded, Ix, Read, Show)
--- @ClockTime@ is an abstract type, used for the internal clock time.
+-- | A representation of the internal clock time.
-- Clock times may be compared, converted to strings, or converted to an
--- external calendar time @CalendarTime@.
-
-data ClockTime = TOD Integer -- Seconds since 00:00:00 on 1 Jan 1970
- Integer -- Picoseconds with the specified second
+-- external calendar time 'CalendarTime' for I\/O or other manipulations.
+
+data ClockTime = TOD Integer Integer
+ -- ^ Construct a clock time. The arguments are a number
+ -- of seconds since 00:00:00 (UTC) on 1 January 1970,
+ -- and an additional number of picoseconds.
+ --
+ -- In Haskell 98, the 'ClockTime' type is abstract.
deriving (Eq, Ord)
-- When a ClockTime is shown, it is converted to a CalendarTime in the current
(unsafePerformIO (toCalendarTime t)))
{-
-@CalendarTime@ is a user-readable and manipulable
-representation of the internal $ClockTime$ type. The
-numeric fields have the following ranges.
+The numeric fields have the following ranges.
\begin{verbatim}
Value Range Comments
----- ----- --------
year -maxInt .. maxInt [Pre-Gregorian dates are inaccurate]
-mon 0 .. 11 [Jan = 0, Dec = 11]
day 1 .. 31
hour 0 .. 23
min 0 .. 59
sec 0 .. 61 [Allows for two leap seconds]
picosec 0 .. (10^12)-1 [This could be over-precise?]
-wday 0 .. 6 [Sunday = 0, Saturday = 6]
yday 0 .. 365 [364 in non-Leap years]
tz -43200 .. 43200 [Variation from UTC in seconds]
\end{verbatim}
-
-The {\em tzname} field is the name of the time zone. The {\em isdst}
-field indicates whether Daylight Savings Time would be in effect.
-}
+-- | 'CalendarTime' is a user-readable and manipulable
+-- representation of the internal 'ClockTime' type.
+
data CalendarTime
= CalendarTime {
- ctYear :: Int,
- ctMonth :: Month,
- ctDay :: Int,
- ctHour :: Int,
- ctMin :: Int,
- ctSec :: Int,
- ctPicosec :: Integer,
- ctWDay :: Day,
- ctYDay :: Int,
- ctTZName :: String,
- ctTZ :: Int,
- ctIsDST :: Bool
+ ctYear :: Int -- ^ Year (pre-Gregorian dates are inaccurate)
+ , ctMonth :: Month -- ^ Month of the year
+ , ctDay :: Int -- ^ Day of the month (1 to 31)
+ , ctHour :: Int -- ^ Hour of the day (0 to 23)
+ , ctMin :: Int -- ^ Minutes (0 to 59)
+ , ctSec :: Int -- ^ Seconds (0 to 61, allowing for up to
+ -- two leap seconds)
+ , ctPicosec :: Integer -- ^ Picoseconds
+ , ctWDay :: Day -- ^ Day of the week
+ , ctYDay :: Int -- ^ Day of the year
+ -- (0 to 364, or 365 in leap years)
+ , ctTZName :: String -- ^ Name of the time zone
+ , ctTZ :: Int -- ^ Variation from UTC in seconds
+ , ctIsDST :: Bool -- ^ 'True' if Daylight Savings Time would
+ -- be in effect, and 'False' otherwise
}
deriving (Eq,Ord,Read,Show)
--- The @TimeDiff@ type records the difference between two clock times in
--- a user-readable way.
+-- | records the difference between two clock times in a user-readable way.
data TimeDiff
= TimeDiff {
}
deriving (Eq,Ord,Read,Show)
+-- | null time difference.
+
noTimeDiff :: TimeDiff
noTimeDiff = TimeDiff 0 0 0 0 0 0 0
-- -----------------------------------------------------------------------------
--- getClockTime returns the current time in its internal representation.
+-- | returns the current time in its internal representation.
getClockTime :: IO ClockTime
#ifdef __HUGS__
#endif
-- -----------------------------------------------------------------------------
--- addToClockTime d t adds a time difference d and a
--- clock time t to yield a new clock time. The difference d
--- may be either positive or negative. diffClockTimes t1 t2 returns
--- the difference between two clock times t1 and t2 as a TimeDiff.
+-- | @'addToClockTime' d t@ adds a time difference @d@ and a
+-- clock time @t@ to yield a new clock time. The difference @d@
+-- may be either positive or negative.
addToClockTime :: TimeDiff -> ClockTime -> ClockTime
addToClockTime (TimeDiff year mon day hour min sec psec)
in
toClockTime cal{ctMonth=month', ctYear=year'}
+-- | @'diffClockTimes' t1 t2@ returns the difference between two clock
+-- times @t1@ and @t2@ as a 'TimeDiff'.
+
diffClockTimes :: ClockTime -> ClockTime -> TimeDiff
-- diffClockTimes is meant to be the dual to `addToClockTime'.
-- If you want to have the TimeDiff properly splitted, use
}
+-- | converts a time difference to normal form.
+
normalizeTimeDiff :: TimeDiff -> TimeDiff
-- FIXME: handle psecs properly
-- FIXME: ?should be called by formatTimeDiff automagically?
#else /* ! HAVE_TM_ZONE */
# if HAVE_TZNAME || defined(_WIN32)
-# if cygwin32_TARGET_OS
+# if cygwin32_HOST_OS
# define tzname _tzname
# endif
-# ifndef mingw32_TARGET_OS
+# ifndef mingw32_HOST_OS
foreign import ccall unsafe "time.h &tzname" tzname :: Ptr (Ptr CChar)
# else
foreign import ccall unsafe "__hscore_timezone" timezone :: Ptr CLong
gmtoff x = do
dst <- (#peek struct tm,tm_isdst) x
tz <- if dst then peek altzone else peek timezone
- return (-fromIntegral tz)
+ let realToInteger = round . realToFrac :: Real a => a -> Integer
+ return (-fromIntegral (realToInteger tz))
# else /* ! HAVE_DECL_ALTZONE */
-#if !defined(mingw32_TARGET_OS)
+#if !defined(mingw32_HOST_OS)
foreign import ccall "time.h &timezone" timezone :: Ptr CLong
#endif
#endif /* ! __HUGS__ */
-- -----------------------------------------------------------------------------
--- toCalendarTime t converts t to a local time, modified by
--- the current timezone and daylight savings time settings. toUTCTime
--- t converts t into UTC time. toClockTime l converts l into the
--- corresponding internal ClockTime. The wday, yday, tzname, and isdst fields
--- are ignored.
-
+-- | converts an internal clock time to a local time, modified by the
+-- timezone and daylight savings time settings in force at the time
+-- of conversion. Because of this dependence on the local environment,
+-- 'toCalendarTime' is in the 'IO' monad.
toCalendarTime :: ClockTime -> IO CalendarTime
#ifdef __HUGS__
toCalendarTime = clockToCalendarTime_static localtime False
#endif
+-- | converts an internal clock time into a 'CalendarTime' in standard
+-- UTC format.
+
toUTCTime :: ClockTime -> CalendarTime
#ifdef __HUGS__
toUTCTime = unsafePerformIO . toCalTime True
(if is_utc then False else isdst /= 0))
#endif /* ! __HUGS__ */
+-- | converts a 'CalendarTime' into the corresponding internal
+-- 'ClockTime', ignoring the contents of the 'ctWDay', 'ctYDay',
+-- 'ctTZName' and 'ctIsDST' fields.
+
toClockTime :: CalendarTime -> ClockTime
#ifdef __HUGS__
toClockTime (CalendarTime yr mon mday hour min sec psec
-- -----------------------------------------------------------------------------
-- Converting time values to strings.
+-- | formats calendar times using local conventions.
+
calendarTimeToString :: CalendarTime -> String
calendarTimeToString = formatCalendarTime defaultTimeLocale "%c"
+-- | formats calendar times using local conventions and a formatting string.
+-- The formatting string is that understood by the ISO C @strftime()@
+-- function.
+
formatCalendarTime :: TimeLocale -> String -> CalendarTime -> String
formatCalendarTime l fmt (CalendarTime year mon day hour min sec _
wday yday tzname _ _) =
where x' = x `rem` 100
show3 x = show (x `quot` 100) ++ show2 (x `rem` 100)
- where x' = x `rem` 1000
to12 :: Int -> Int
to12 h = let h' = h `mod` 12 in if h' == 0 then 12 else h'
-- Useful extensions for formatting TimeDiffs.
+-- | formats time differences using local conventions.
+
timeDiffToString :: TimeDiff -> String
timeDiffToString = formatTimeDiff defaultTimeLocale "%c"
+-- | formats time differences using local conventions and a formatting string.
+-- The formatting string is that understood by the ISO C @strftime()@
+-- function.
+
formatTimeDiff :: TimeLocale -> String -> TimeDiff -> String
formatTimeDiff l fmt td@(TimeDiff year month day hour min sec _)
= doFmt fmt
#if HAVE_FTIME
type CTimeB = ()
-#ifndef mingw32_TARGET_OS
+#ifndef mingw32_HOST_OS
foreign import ccall unsafe "time.h ftime" ftime :: Ptr CTimeB -> IO CInt
#else
foreign import ccall unsafe "time.h ftime" ftime :: Ptr CTimeB -> IO ()