Optimized as possible as I can.

[Lucu.git] / Network / HTTP / Lucu / Utils.hs

diff --git a/Network/HTTP/Lucu/Utils.hs b/Network/HTTP/Lucu/Utils.hs
index 1619f364e9de60a0738491f3bcc280593410905b..b22780b5f121aab681722b8ac17333f41ba3a66e 100644 (file)
--- a/Network/HTTP/Lucu/Utils.hs
+++ b/Network/HTTP/Lucu/Utils.hs
@@ -5,6 +5,7 @@ module Network.HTTP.Lucu.Utils
     , joinWith
     , trim
     , noCaseEq
+    , noCaseEq'
     , isWhiteSpace
     , quoteStr
     , parseWWWFormURLEncoded
@@ -22,7 +23,8 @@ import Network.URI
 --  > ==> ["ab", "c", "def"]
 splitBy :: (a -> Bool) -> [a] -> [[a]]
 splitBy isSeparator src
-    = case break isSeparator src
+    = isSeparator `seq`
+      case break isSeparator src
       of (last , []      ) -> last  : []
          (first, sep:rest) -> first : splitBy isSeparator rest
 
@@ -30,25 +32,40 @@ splitBy isSeparator src
 --  > ==> "ab:c:def"
 joinWith :: [a] -> [[a]] -> [a]
 joinWith separator xs
-    = foldr (++) [] $ intersperse separator xs
+    = separator `seq` xs `seq`
+      foldr (++) [] $! intersperse separator xs
 
 -- |> trim (== '_') "__ab_c__def___"
 --  > ==> "ab_c__def"
 trim :: (a -> Bool) -> [a] -> [a]
-trim p = trimTail . trimHead
+trim p = p `seq` trimTail . trimHead
     where
       trimHead = dropWhile p
       trimTail = reverse . trimHead . reverse
 
 -- |@'noCaseEq' a b@ is equivalent to @(map toLower a) == (map toLower
--- b)@
+-- b)@. See 'noCaseEq''.
 noCaseEq :: String -> String -> Bool
 noCaseEq a b
     = (map toLower a) == (map toLower b)
+{-# INLINE noCaseEq #-}
+
+-- |@'noCaseEq'' a b@ is a variant of 'noCaseEq' which first checks
+-- the length of two strings to avoid possibly unnecessary comparison.
+noCaseEq' :: String -> String -> Bool
+noCaseEq' a b
+    | length a /= length b = False
+    | otherwise            = noCaseEq a b
+{-# INLINE noCaseEq' #-}
 
 -- |@'isWhiteSpace' c@ is True iff c is one of SP, HT, CR and LF.
 isWhiteSpace :: Char -> Bool
-isWhiteSpace = flip elem " \t\r\n"
+isWhiteSpace ' '  = True
+isWhiteSpace '\t' = True
+isWhiteSpace '\r' = True
+isWhiteSpace '\n' = True
+isWhiteSpace _    = False
+{-# INLINE isWhiteSpace #-}
 
 -- |> quoteStr "abc"
 --  > ==> "\"abc\""
@@ -56,7 +73,8 @@ isWhiteSpace = flip elem " \t\r\n"
 --  > quoteStr "ab\"c"
 --  > ==> "\"ab\\\"c\""
 quoteStr :: String -> String
-quoteStr str = foldr (++) "" (["\""] ++ map quote str ++ ["\""])
+quoteStr str = str `seq`
+               foldr (++) "" (["\""] ++ map quote str ++ ["\""])
     where
       quote :: Char -> String
       quote '"' = "\\\""