Better name-rewriting engine

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

diff --git a/Network/HTTP/Lucu/HttpVersion.hs b/Network/HTTP/Lucu/HttpVersion.hs
index 9b955d37fd9644beb912feb1808a1f2982dd97b9..4466f1ecda8959aa102e76e6137cd57c8b53e420 100644 (file)
--- a/Network/HTTP/Lucu/HttpVersion.hs
+++ b/Network/HTTP/Lucu/HttpVersion.hs
@@ -1,20 +1,26 @@
+{-# LANGUAGE
+    OverloadedStrings
+  , UnicodeSyntax
+  #-}
+-- |An internal module for HTTP version numbers.
 module Network.HTTP.Lucu.HttpVersion
     ( HttpVersion(..)
-    , httpVersionP    -- Parser HttpVersion
-    , hPutHttpVersion -- Handle -> HttpVersion -> IO ()
+    , printHttpVersion
+    , httpVersion
     )
     where
-
-import qualified Data.ByteString.Lazy.Char8 as B
-import           Data.ByteString.Lazy.Char8 (ByteString)
-import           Network.HTTP.Lucu.Parser
-import           System.IO
-
-data HttpVersion = HttpVersion Int Int
-                   deriving (Eq)
-
-instance Show HttpVersion where
-    show (HttpVersion maj min) = "HTTP/" ++ show maj ++ "." ++ show min
+import Control.Applicative
+import Control.Applicative.Unicode
+import Data.Ascii (AsciiBuilder)
+import qualified Data.Ascii as A
+import Data.Attoparsec.Char8
+import Data.Monoid.Unicode
+import Prelude hiding (min)
+
+-- |An HTTP version consists of major and minor versions.
+data HttpVersion
+    = HttpVersion !Int !Int
+      deriving (Eq, Show)
 
 instance Ord HttpVersion where
     (HttpVersion majA minA) `compare` (HttpVersion majB minB)
@@ -24,18 +30,22 @@ instance Ord HttpVersion where
         | minA < minB = LT
         | otherwise   = EQ
 
-
-httpVersionP :: Parser HttpVersion
-httpVersionP = do string "HTTP/"
-                  major <- many1 digit
-                  char '.'
-                  minor <- many1 digit
-                  return $ HttpVersion (read major) (read minor)
-
-
-hPutHttpVersion :: Handle -> HttpVersion -> IO ()
-hPutHttpVersion h (HttpVersion maj min)
-    = do hPutStr  h "HTTP/"
-         hPutStr  h (show maj)
-         hPutChar h '.'
-         hPutStr  h (show min)
\ No newline at end of file
+-- |Convert an 'HttpVersion' to 'AsciiBuilder'.
+printHttpVersion ∷ HttpVersion → AsciiBuilder
+printHttpVersion v
+    = case v of
+        -- Optimisation for special cases.
+        HttpVersion 1 0 → A.toAsciiBuilder "HTTP/1.0"
+        HttpVersion 1 1 → A.toAsciiBuilder "HTTP/1.1"
+        -- General (but almost never stumbling) cases.
+        HttpVersion maj min
+            → A.toAsciiBuilder "HTTP/" ⊕
+              A.toAsciiBuilder (A.unsafeFromString $ show maj) ⊕
+              A.toAsciiBuilder "." ⊕
+              A.toAsciiBuilder (A.unsafeFromString $ show min)
+
+-- |'Parser' for an 'HttpVersion'.
+httpVersion ∷ Parser HttpVersion
+httpVersion = string "HTTP/"
+              *>
+              (HttpVersion <$> decimal ⊛ (char '.' *> decimal))