Exodus to GHC 6.8.1

[Rakka.git] / Rakka / Utils.hs

diff --git a/Rakka/Utils.hs b/Rakka/Utils.hs
index cb77474553c42fee4f6cdcaf340a32a8db4e38a9..f58a0b8a30340070dfc0c9b715371fedfb75cdb8 100644 (file)
--- a/Rakka/Utils.hs
+++ b/Rakka/Utils.hs
@@ -1,13 +1,22 @@
 module Rakka.Utils
-    ( parseYesOrNo
+    ( yesOrNo
+    , parseYesOrNo
     , maybeA
-    , defaultTo
     , deleteIfEmpty
+    , formatW3CDateTime
+    , chomp
     )
     where
 
 import           Control.Arrow
 import           Control.Arrow.ArrowList
+import           Data.Time
+import           Text.Printf
+
+
+yesOrNo :: Bool -> String
+yesOrNo True  = "yes"
+yesOrNo False = "no"
 
 
 parseYesOrNo :: ArrowChoice a => a String Bool
@@ -26,15 +35,55 @@ maybeA a = listA a
                         (x:_) -> returnA -< Just x
 
 
-defaultTo :: ArrowChoice a => b -> a (Maybe b) b
-defaultTo def
-    = proc m -> case m of
-                  Nothing -> returnA -< def
-                  Just x  -> returnA -< x
-
-
 deleteIfEmpty :: (ArrowList a, ArrowChoice a) => a String String
 deleteIfEmpty
     = proc str -> do case str of
                        "" -> none    -< ()
-                       _  -> returnA -< str
\ No newline at end of file
+                       _  -> returnA -< str
+
+
+formatW3CDateTime :: ZonedTime -> String
+formatW3CDateTime zonedTime
+    = formatLocalTime (zonedTimeToLocalTime zonedTime)
+      ++
+      formatTimeZone (zonedTimeZone zonedTime)
+    where
+      formatLocalTime :: LocalTime -> String
+      formatLocalTime localTime
+          = let (year, month, day) = toGregorian (localDay localTime)
+                timeOfDay          = localTimeOfDay localTime
+                (secInt, secFrac)  = properFraction (todSec timeOfDay)
+            in
+              (printf "%04d-%02d-%02dT%02d:%02d:%02d"
+                      year
+                      month
+                      day
+                      (todHour timeOfDay)
+                      (todMin timeOfDay)
+                      (secInt :: Int))
+              ++
+              (if secFrac == 0
+               then ""
+               else tail (show secFrac))
+      
+      formatTimeZone :: TimeZone -> String
+      formatTimeZone tz
+          = case timeZoneMinutes tz of
+              offset | offset <  0 -> '-':(showTZ $ negate offset)
+                     | offset == 0 -> "Z"
+                     | otherwise   -> '+':(showTZ offset)
+      
+      showTZ :: Int -> String   
+      showTZ offset
+          = let hour   = offset `div` 60
+                minute = offset - hour * 60
+            in 
+              show2 hour ++ ":" ++ show2 minute
+            
+      show2 :: Int -> String
+      show2 n | n < 10    = '0':(show n)
+              | otherwise = show n
+
+
+chomp :: String -> String
+chomp = reverse . snd . break (/= '\n') . reverse