Code clean-up using convertible-text

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

diff --git a/Network/HTTP/Lucu/ETag.hs b/Network/HTTP/Lucu/ETag.hs
index 0341f5ac382b245638575477b0474ec0b1fafe40..3ebfc1d91b35b3f7e676571d0ed981a813b67dbf 100644 (file)
--- a/Network/HTTP/Lucu/ETag.hs
+++ b/Network/HTTP/Lucu/ETag.hs
@@ -1,46 +1,98 @@
+{-# LANGUAGE
+    DeriveDataTypeable
+  , FlexibleInstances
+  , MultiParamTypeClasses
+  , OverloadedStrings
+  , RecordWildCards
+  , TemplateHaskell
+  , UnicodeSyntax
+  #-}
+-- |An internal module for entity tags.
 module Network.HTTP.Lucu.ETag
-    ( ETag
-    , mkETag    -- Bool -> String -> ETag
-    , eTagP     -- Parser ETag
-    , eTagListP -- Parser [ETag]
+    ( ETag(..)
+
+    , strongETag
+    , weakETag
+    , eTag
+    , eTagList
     )
     where
+import Control.Applicative
+import Control.Monad
+import Data.Ascii (Ascii, AsciiBuilder)
+import Data.Attoparsec.Char8
+import Data.Convertible.Base
+import Data.Convertible.Instances.Ascii ()
+import Data.Convertible.Utils
+import Data.Data
+import Data.Monoid.Unicode
+import Language.Haskell.TH.Syntax
+import Network.HTTP.Lucu.OrphanInstances ()
+import Network.HTTP.Lucu.Parser.Http hiding (token)
+import Network.HTTP.Lucu.Utils
+import Prelude.Unicode
 
-import           Network.HTTP.Lucu.Parser
-import           Network.HTTP.Lucu.Parser.Http
-
-
+-- |An entity tag consists of a weakness flag and an opaque string.
 data ETag = ETag {
-      etagIsWeak :: Bool
-    , etagToken  :: String
-    } deriving (Eq)
+      -- |The weakness flag. Weak tags looks like @W\/\"blahblah\"@
+      -- and strong tags are like @\"blahblah\"@. See:
+      -- <http://www.w3.org/Protocols/rfc2616/rfc2616-sec13.html#sec13.3.3>
+      etagIsWeak ∷ !Bool
+      -- |An opaque string. Only characters from 0x20 (sp) to 0x7e (~)
+      -- are allowed.
+    , etagToken  ∷ !Ascii
+    } deriving (Eq, Show, Data, Typeable)
 
+instance Lift ETag where
+    lift (ETag {..})
+        = [| ETag {
+               etagIsWeak = $(lift etagIsWeak)
+             , etagToken  = $(lift etagToken )
+             }
+           |]
 
-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]
+instance ConvertSuccess ETag Ascii where
+    {-# INLINE convertSuccess #-}
+    convertSuccess = convertSuccessVia ((⊥) ∷ AsciiBuilder)
 
+instance ConvertSuccess ETag AsciiBuilder where
+    {-# INLINE convertSuccess #-}
+    convertSuccess (ETag {..})
+        = ( if etagIsWeak then
+                cs ("W/" ∷ Ascii)
+            else
+                (∅)
+          )
+          ⊕
+          quoteStr etagToken
 
-mkETag :: Bool -> String -> ETag
-mkETag = ETag
+deriveAttempts [ ([t| ETag |], [t| Ascii        |])
+               , ([t| ETag |], [t| AsciiBuilder |])
+               ]
 
+-- |This is equivalent to @'ETag' 'False'@. If you want to generate an
+-- ETag from a file, try using
+-- 'Network.HTTP.Lucu.StaticFile.generateETagFromFile'.
+strongETag ∷ Ascii → ETag
+{-# INLINE strongETag #-}
+strongETag = ETag False
 
-eTagP :: Parser ETag
-eTagP = do isWeak <- option False (string "W/" >> return True)
-           str    <- quotedStr
-           return $ mkETag isWeak str
+-- |This is equivalent to @'ETag' 'True'@.
+weakETag ∷ Ascii → ETag
+{-# INLINE weakETag #-}
+weakETag = ETag True
 
+-- |'Parser' for an 'ETag'.
+eTag ∷ Parser ETag
+{-# INLINEABLE eTag #-}
+eTag = do isWeak ← option False (string "W/" *> return True)
+          str    ← quotedStr
+          return $ ETag isWeak str
 
-eTagListP :: Parser [ETag]
-eTagListP = allowEOF
-            $ sepBy1 eTagP (do many sp
-                               char ','
-                               many sp)
+-- |'Parser' for a list of 'ETag's.
+eTagList ∷ Parser [ETag]
+{-# INLINEABLE eTagList #-}
+eTagList = do xs ← listOf eTag
+              when (null xs) $
+                  fail "empty list of ETags"
+              return xs