cleaning, adding :set to affect parsing, closes #169

src/IHaskell/Eval/Evaluate.hs

@@ -462,21 +462,29 @@ evalCommand output (Directive SetExtension opts) state = do
 
 evalCommand a (Directive SetOption opts) state = do
   write $ "Option: " ++ opts
-  let (lost, found) = partitionEithers
-        [ case filter (elem w . getOptionName) kernelOpts of
-                [x] -> Right (getUpdateKernelState x)
-                [] -> Left w
-                ds -> error ("kernelOpts has duplicate:" ++ show (map getOptionName ds))
-          | w <- words opts ]
-      warn
-        | null lost = mempty
-        | otherwise = displayError ("Could not recognize options: " ++ intercalate "," lost)
+  let (existing, nonExisting) = partition optionExists $ words opts
+  if not $ null nonExisting
+  then
+    let err = "No such options: " ++ intercalate ", " nonExisting in
     return EvalOut {
-    evalStatus = if null lost then Success else Failure,
-    evalResult = warn,
-    evalState = foldl' (flip ($)) state found,
+      evalStatus = Failure,
+      evalResult = displayError err,
+      evalState = state,
+      evalPager = ""
+    }
+  else
+    let options = mapMaybe findOption $ words opts
+        updater = foldl' (.) id $ map getUpdateKernelState options in
+      return EvalOut {
+        evalStatus = Success,
+        evalResult = mempty,
+        evalState = updater state,
         evalPager = ""
       }
+  where
+    optionExists = isJust . findOption
+    findOption opt =
+      find (elem opt . getOptionName) kernelOpts
 
 evalCommand _ (Directive GetType expr) state = wrapExecution state $ do
   write $ "Type: " ++ expr

src/IHaskell/Eval/Parser.hs

@@ -125,7 +125,10 @@ parseString codeString = do
 
 activateParsingExtensions :: GhcMonad m => CodeBlock -> m ()
 activateParsingExtensions (Directive SetExtension ext) = void $ setExtension ext
-activateParsingExtensions _ = return ()
+activateParsingExtensions (Directive SetDynFlag flags) = 
+  case stripPrefix "-X" flags of
+    Just ext -> void $ setExtension ext
+    Nothing -> return ()
 
 -- | Parse a single chunk of code, as indicated by the layout of the code.
 parseCodeChunk :: GhcMonad m => String -> LineNumber  -> m CodeBlock
@@ -251,16 +254,16 @@ parseDirective (':':directive) line = case find rightDirective directives of
       [] -> False
       dir:_ -> dir `elem` tail (inits dirname)
     directives =
-      [(GetType,      "type")
-      ,(GetInfo,      "info")
-      ,(SearchHoogle, "hoogle")
-      ,(GetDoc,       "documentation")
-      ,(SetDynFlag,   "set")
-      ,(LoadFile,     "load")
-      ,(SetOption,    "option")
-      ,(SetExtension, "extension")
-      ,(GetHelp,      "?")
-      ,(GetHelp,      "help")
+      [ (GetType,      "type")
+      , (GetInfo,      "info")
+      , (SearchHoogle, "hoogle")
+      , (GetDoc,       "documentation")
+      , (SetDynFlag,   "set")
+      , (LoadFile,     "load")
+      , (SetOption,    "option")
+      , (SetExtension, "extension")
+      , (GetHelp,      "?")
+      , (GetHelp,      "help")
       ]
 parseDirective _ _ = error "Directive must start with colon!"