Supplession of unneeded imports

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

diff --git a/Network/HTTP/Lucu/Utils.hs b/Network/HTTP/Lucu/Utils.hs
index 58da6f50c2612ac1e64e4d8366e17dfa21712f50..d6e46f180e1d2c61990979cd96506b48dcacb6c5 100644 (file)
--- a/Network/HTTP/Lucu/Utils.hs
+++ b/Network/HTTP/Lucu/Utils.hs
@@ -1,51 +1,92 @@
+-- |Utility functions used internally in the Lucu httpd. These
+-- functions may be useful too for something else.
 module Network.HTTP.Lucu.Utils
-    ( splitBy      -- (a -> Bool) -> [a] -> [[a]]
-    , joinWith     -- [a] -> [[a]] -> [a]
-    , trim         -- (a -> Bool) -> [a] -> [a]
-    , noCaseEq     -- String -> String -> Bool
-    , isWhiteSpace -- Char -> Bool
-    , quoteStr     -- String -> String
+    ( splitBy
+    , joinWith
+    , trim
+    , noCaseEq
+    , noCaseEq'
+    , isWhiteSpace
+    , quoteStr
+    , parseWWWFormURLEncoded
     )
     where
 
-import Control.Monad.Trans
 import Data.Char
 import Data.List
-import Foreign
-import Foreign.C
-
+import Network.URI
 
+-- |> splitBy (== ':') "ab:c:def"
+--  > ==> ["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
 
-
+-- |> joinWith ':' ["ab", "c", "def"]
+--  > ==> "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)@. 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\""
+--
+--  > 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 '"' = "\\\""
-      quote c   = [c]
\ No newline at end of file
+      quote c   = [c]
+
+
+-- |> parseWWWFormURLEncoded "aaa=bbb&ccc=ddd"
+--  > ==> [("aaa", "bbb"), ("ccc", "ddd")]
+parseWWWFormURLEncoded :: String -> [(String, String)]
+parseWWWFormURLEncoded src
+    | src == "" = []
+    | otherwise = do pairStr <- splitBy (\ c -> c == ';' || c == '&') src
+                     let (key, value) = break (== '=') pairStr
+                     return ( unEscapeString key
+                            , unEscapeString $ case value of
+                                                 ('=':val) -> val
+                                                 ""        -> ""
+                            )