Fixed text/bytestring handling in Main, as per @aavogt's PR

src/Main.hs

@@ -11,7 +11,7 @@ import Prelude        (last, read)
 import            Control.Concurrent        (threadDelay)
 import            Control.Concurrent.Chan
 import            Data.Aeson
-import            Data.String.Utils         (strip)
+import            Data.Text                 (strip)
 import            System.Directory
 import            System.Exit               (exitSuccess)
 import            Text.Printf
@@ -19,6 +19,7 @@ import            System.Posix.Signals
 import qualified  Data.Map                  as Map
 
 -- IHaskell imports.
+import            IHaskell.Convert          (convert)
 import            IHaskell.Eval.Completion  (complete)
 import            IHaskell.Eval.Evaluate
 import            IHaskell.Display
@@ -34,7 +35,6 @@ import qualified  IPython.Stdin             as Stdin
 
 -- GHC API imports.
 import GHC        hiding (extensions, language)
-import Outputable (showSDoc, ppr)
 
 -- | Compute the GHC API version number using the dist/build/autogen/cabal_macros.h
 ghcVersionInts :: [Int]
@@ -62,6 +62,8 @@ ihaskell :: Args -> IO ()
 ihaskell (Args (ShowHelp help) _) =
   putStrLn $ pack help
 
+ihaskell (Args ConvertLhs args) = convert args
+
 ihaskell (Args Console flags) = showingHelp Console flags $ do
   ipython <- chooseIPython flags
   setupIPython ipython
@@ -274,9 +276,9 @@ replyTo interface req@ExecuteRequest{ getCode = code } replyHeader state = do
         header <- dupHeader replyHeader DisplayDataMessage
         send $ PublishDisplayData header "haskell" $ map convertSvgToHtml outs
 
-      convertSvgToHtml (DisplayData MimeSvg svg) = html $ makeSvgImg $ base64 svg
+      convertSvgToHtml (DisplayData MimeSvg svg) = html $ makeSvgImg $ base64 $ encodeUtf8 svg
       convertSvgToHtml x = x
-      makeSvgImg base64data = Chars.unpack $ "<img src=\"data:image/svg+xml;base64," ++ base64data ++ "\"/>"
+      makeSvgImg base64data = unpack $ "<img src=\"data:image/svg+xml;base64," ++ base64data ++ "\"/>"
 
       publish :: EvaluationResult -> IO ()
       publish result = do
@@ -310,9 +312,9 @@ replyTo interface req@ExecuteRequest{ getCode = code } replyHeader state = do
   let execCount = getExecutionCounter state
   -- Let all frontends know the execution count and code that's about to run
   inputHeader <- liftIO $ dupHeader replyHeader InputMessage
-  send $ PublishInput inputHeader (Chars.unpack code) execCount
+  send $ PublishInput inputHeader (unpack code) execCount
   -- Run code and publish to the frontend as we go.
-  updatedState <- evaluate state (Chars.unpack code) publish
+  updatedState <- evaluate state (unpack code) publish
 
   -- Notify the frontend that we're done computing.
   idleHeader <- liftIO $ dupHeader replyHeader StatusMessage
@@ -328,16 +330,16 @@ replyTo interface req@ExecuteRequest{ getCode = code } replyHeader state = do
 
 
 replyTo _ req@CompleteRequest{} replyHeader state = do
-  let line = Chars.unpack $ getCodeLine req
-  (matchedText, completions) <- complete line (getCursorPos req)
+  let line = getCodeLine req
+  (matchedText, completions) <- complete (unpack line) (getCursorPos req)
 
-  let reply =  CompleteReply replyHeader completions matchedText line True
+  let reply =  CompleteReply replyHeader (map pack completions) (pack matchedText) line True
   return (state,  reply)
 
 -- | Reply to the object_info_request message. Given an object name, return
 -- | the associated type calculated by GHC.
 replyTo _ ObjectInfoRequest{objectName = oname} replyHeader state = do
-  docs <- info oname
+  docs <- pack <$> info (unpack oname)
   let reply = ObjectInfoReply {
                 header = replyHeader,
                 objectName = oname,