Formatting dates

Formatting date strings

Add old-locale to .cabal.

import Data.Time
import System.Locale (defaultTimeLocale)

dateFormat = "%e %b %Y"
dateFormat :: String
dateTimeFormat = "%e %b %Y %H:%M:%S"
dateTimeFormat :: String

formatDateStr :: String -> String
formatDateStr dateString = formatTime defaultTimeLocale dateTimeFormat t
    where 
        t = read dateString
        t :: UTCTime
    
main = print $ formatDateStr "2012-09-15 00:07:31.874712 UTC"

Formatting day values

Useful when you use a Day field and jQuery date picker.

import Data.Time
import System.Locale (defaultTimeLocale)

dateFormat = "%e %b %Y"
dateFormat :: String
dateTimeFormat = "%e %b %Y %H:%M:%S"
dateTimeFormat :: String

formatDay :: Day -> String
formatDay day = formatTime defaultTimeLocale dateFormat t
    where 
        t = UTCTime day 0
        t :: UTCTime
    
main = do
    now <- getCurrentTime
    let today = utctDay now
    print $ formatDay today