herf-time

Haskell's time library is nice but I wanted to be able to do some of the operations in the Kerf programming language.

By creating a set of type classes: HerfedTime , ToUTCHerfTime, FromUTCHerfTime I think there is a nice mechanism to do just that.

any instance of these 3 classes should satisfy the law:

• Path Independant on all addtion
• addX a X == unherf (addX (herf a) X )
  • where: addX := {addYear , addMonth, addWeek ...}

Usage

Add Intervals

>>> date 2016 01 01 `add` hour 3 `add` week 16 `add` month 3 :: UTCTime
UTCHerfTime 2016-07-22 03:00:00 UTC

Subtract Intervals

>>> date 2016 01 01 `add` hour (-3) `add` week (-16) `add` month (-3) :: UTCTime
UTCHerfTime 2015-06-10 21:00:00 UTC

Represent Time in Multiple Ways

>>> dateTime 2016 01 01 01 23 01 `add` hour 3 `add` week 16 `add` month 3 :: UTCTime
UTCHerfTime 2016-07-22 04:23:01 UTC
>>> dateTimePico 2016 01 01 01 23 01 01 `add` hour 3 `add` week 16 `add` month 3 :: UTCTime
UTCHerfTime 2016-07-22 04:23:01.000000000001 UTC

Get Times in any HerfedTime format (UTC for example)

>>> date 2016 01 01 `add` hour 3 `add` week 16 `add` month 3   :: UTCTime
2016-07-22 03:00:00 UTC

Use HerfTime.ZonedTime to convert easily between times

(reherf $ ( dateTime 2016 01 01 01 01 01 :: HerfZonedTime "CST")) :: HerfZonedTime "PST" 2015-12-31T23:01:01:PST

Some fancier examples (Using HerfTime.ZonedTime)

λ> zt <- getZonedTime
λ> herfShow zt
"2016-01-21T11:29:05:CST"
λ> reherfz zt :: HerfZonedTime "PST"
2016-01-21T09:29:05:PST
λ> reherfz zt :: HerfZonedTime "+0600"
2016-01-21T23:29:05:+0600
λ> reherfz zt :: HerfZonedTime "CST"
2016-01-21T11:29:05:CST
λ> (reherfz zt) `add` month 2 :: HerfZonedTime "CST"
2016-03-21T11:29:05:CST

-- What time will it be exactly 3 months from now in California?
λ> (reherfz zt) `add` month 2 :: HerfZonedTime "PST"
2016-03-21T09:29:05:PST

cabal configure --enable-tests && cabal build && cabal test