use a foldr

Should be faster here.

PresenceLog.hs

@@ -26,7 +26,7 @@ module PresenceLog (
 import Data.Time.Clock.POSIX
 import Data.Time
 import System.Locale
-import qualified Data.Map as Map
+import qualified Data.Map as M
 import Control.Monad.State (liftIO)
 import Control.Applicative
 
@@ -111,18 +111,18 @@ filterPresent = filter (\l -> InfoPresent == status l) . compactLog
 {- Compacts a set of logs, returning a subset that contains the current
  - status. -}
 compactLog :: [LogLine] -> [LogLine]
-compactLog = Map.elems . foldl mapLog Map.empty
+compactLog = M.elems . foldr mapLog M.empty
 
-type LogMap = Map.Map String LogLine
+type LogMap = M.Map String LogLine
 
 {- Inserts a log into a map of logs, if the log has better (ie, newer)
  - information than the other logs in the map -}
-mapLog :: LogMap -> LogLine -> LogMap
-mapLog m l = 
+mapLog :: LogLine -> LogMap -> LogMap
+mapLog l m = 
 	if better
-		then Map.insert i l m
+		then M.insert i l m
 		else m
 	where
-		better = maybe True newer $ Map.lookup i m
+		better = maybe True newer $ M.lookup i m
 		newer l' = date l' <= date l
 		i = info l