Make the analysis parallel (#2)

Co-authored-by: Mats Rauhala <mats.rauhala@iki.fi>
Reviewed-on: #2
Co-authored-by: Mats Rauhala <masse@rauhala.info>
Co-committed-by: Mats Rauhala <masse@rauhala.info>

src/Data/Email.hs

@@ -5,12 +5,9 @@ import Data.Email.Header
 
 import Conduit
 import qualified Data.Conduit.Combinators as C
-import qualified Data.Conduit.Text as CT
 
 import Data.ByteString
        (ByteString)
 
 parseEmail :: (MonadUnliftIO m, MonadThrow m, Monad m) => ConduitM ByteString Header m ()
-parseEmail = catchC (CT.decode CT.utf8) err .| CT.lines .| C.concatMap decode
-  where
-    err e = liftIO (print @CT.TextException e) >> yield ""
+parseEmail = C.linesUnboundedAscii .| C.concatMap decode

src/Data/Email/Header.hs

@@ -1,29 +1,25 @@
+{-# LANGUAGE OverloadedStrings #-}
 module Data.Email.Header where
 
-import Data.Text
-       (Text)
-import qualified Data.Text as T
-
 import qualified Data.Foldable as F
 
-import Data.Attoparsec.Text
+import Data.Attoparsec.ByteString.Char8
 
 import Data.Vector
        (Vector)
 import qualified Data.Vector as V
 
-import Data.Char
-       (isSpace)
-
 import Control.Applicative
        ((<|>))
+import Data.ByteString (ByteString)
+import qualified Data.ByteString.Char8 as BC
 
 data Header
-  = From !Text
-  | To !(Vector Text)
+  = From !ByteString
+  | To !(Vector ByteString)
   deriving (Show, Eq)
 
-decode :: Text -> Either String Header
+decode :: ByteString -> Either String Header
 decode = parseOnly parseHeader
   where
     parseHeader :: Parser Header
@@ -33,23 +29,23 @@ decode = parseOnly parseHeader
     parseTo :: Parser Header
     parseTo = To <$> (string "To:" *> emptySpace *> emails)
     emptySpace = many' space
-    emails :: Parser (Vector Text)
+    emails :: Parser (Vector ByteString)
     emails = V.fromList <$> (bracketEmail <|> email) `sepBy` char ','
-    bracketEmail :: Parser Text
+    bracketEmail :: Parser ByteString
     bracketEmail = do
       _ <- manyTill anyChar (char '<')
       email
-    email :: Parser Text
+    email :: Parser ByteString
     email = do
       _ <- many' space
-      name <- T.pack <$> many' (satisfy (\c -> not (isSpace c) && c /= '@'))
+      name <- BC.pack <$> many' (satisfy (\c -> not (isSpace c) && c /= '@'))
       _ <- char '@'
-      rest <- T.pack <$> many' (satisfy (\c -> not (isSpace c) && c /= ',' && c /= '>'))
+      rest <- BC.pack <$> many' (satisfy (\c -> not (isSpace c) && c /= ',' && c /= '>'))
       _ <- many' (notChar ',')
       pure (name <> "@" <> rest)
 
 
-encode :: Header -> Text
+encode :: Header -> ByteString
 encode = \case
   From addr -> "From: " <> addr
-  To addrs -> "To: " <> T.intercalate ", " (F.toList addrs)
+  To addrs -> "To: " <> BC.intercalate ", " (F.toList addrs)