X-Git-Url: http://git.cielonegro.org/gitweb.cgi?a=blobdiff_plain;f=Network%2FHTTP%2FLucu%2FETag.hs;h=d607ad12db4d2fa22ec529a2f0456f9c7e4644f7;hb=1196f43ecedbb123515065f0440844864af906fb;hp=0341f5ac382b245638575477b0474ec0b1fafe40;hpb=1000bdc46cfe7b3ae550ff24ccea9f440f11b42a;p=Lucu.git diff --git a/Network/HTTP/Lucu/ETag.hs b/Network/HTTP/Lucu/ETag.hs index 0341f5a..d607ad1 100644 --- a/Network/HTTP/Lucu/ETag.hs +++ b/Network/HTTP/Lucu/ETag.hs @@ -1,46 +1,58 @@ +{-# OPTIONS_HADDOCK prune #-} + +-- |Manipulation of entity tags. module Network.HTTP.Lucu.ETag - ( ETag - , mkETag -- Bool -> String -> ETag - , eTagP -- Parser ETag - , eTagListP -- Parser [ETag] + ( ETag(..) + , strongETag + , weakETag + , eTagP + , eTagListP ) where +import Control.Monad import Network.HTTP.Lucu.Parser -import Network.HTTP.Lucu.Parser.Http - +import Network.HTTP.Lucu.Parser.Http hiding (token) +import Network.HTTP.Lucu.Utils +-- |An entity tag is made of a weakness flag and a opaque string. data ETag = ETag { - etagIsWeak :: Bool - , etagToken :: String + -- |The weakness flag. Weak tags looks like W\/\"blahblah\" and + -- strong tags are like \"blahblah\". + etagIsWeak :: !Bool + -- |An opaque string. Only characters from 0x20 (sp) to 0x7e (~) + -- are allowed. + , etagToken :: !String } deriving (Eq) - instance Show ETag where show (ETag isWeak token) = (if isWeak then "W/" else "") ++ - foldr (++) "" (["\""] ++ map quote token ++ ["\""]) - where - quote :: Char -> String - quote '"' = "\\\"" - quote c = [c] + quoteStr token +-- |This is equivalent to @'ETag' 'Prelude.False'@. If you want to +-- generate an ETag from a file, try using +-- 'Network.HTTP.Lucu.StaticFile.generateETagFromFile'. +strongETag :: String -> ETag +strongETag = ETag False -mkETag :: Bool -> String -> ETag -mkETag = ETag +-- |This is equivalent to @'ETag' 'Prelude.True'@. +weakETag :: String -> ETag +weakETag = ETag True eTagP :: Parser ETag eTagP = do isWeak <- option False (string "W/" >> return True) str <- quotedStr - return $ mkETag isWeak str + return $ ETag isWeak str eTagListP :: Parser [ETag] eTagListP = allowEOF - $ sepBy1 eTagP (do many sp - char ',' - many sp) + $! do xs <- listOf eTagP + when (null xs) + $ fail "" + return xs