Update lambda handling; better default decode out

src/REPL.hs

@@ -5,35 +5,38 @@ import Lexer
 import Parser
 import Research
 
-import Control.Monad         (void)
+import Control.Monad         		 (void)
 import qualified Data.Map as Map
-import System.IO            (hFlush, stdout)
+import System.Console.Haskeline
+import System.IO            		 (hFlush, stdout)
 
 repl :: Map.Map String T -> IO ()
-repl env = do
-  putStr "sapling < "
-  hFlush stdout
-  input <- getLine
-  case input of
-    ":_exit" ->
-      putStrLn "Goodbye!"
-    ""       -> do
-      putStrLn ""
-      repl env
-    _ -> do
-      let clearEnv = Map.delete "__result" env
-          newEnv   = evalSingle clearEnv (parseSingle input)
-      case Map.lookup "__result" newEnv of
-        Just r  -> do
-          putStrLn $ "sapling > " ++ show r
-          putStrLn $ "DECODE -: " ++ (decodeResult r)
-        Nothing -> pure ()
-      repl newEnv
+repl env = runInputT defaultSettings (loop env)
+  where
+    loop :: Map.Map String T -> InputT IO ()
+    loop env = do
+      minput <- getInputLine "sapling < "
+      case minput of
+        Nothing -> outputStrLn "Goodbye!"
+        Just ":_exit" -> outputStrLn "Goodbye!"
+        Just "" -> do
+          outputStrLn ""
+          loop env
+        Just input -> do
+          let clearEnv = Map.delete "__result" env
+              newEnv   = evalSingle clearEnv (parseSingle input)
+          case Map.lookup "__result" newEnv of
+            Just r -> do
+              outputStrLn $ "sapling > " ++ show r
+              outputStrLn $ "DECODE -: " ++ decodeResult r
+            Nothing -> return ()
+          loop newEnv
 
 decodeResult :: T -> String
-decodeResult tc = 
-  case ofString tc of
+decodeResult tc = case ofNumber tc of
+  Right num -> show num
+  Left _ -> case ofString tc of
     Right str -> "\"" ++ str ++ "\""
-    Left _ -> case ofNumber tc of
-      Right num -> "# " ++ show num
+    Left _ -> case ofList tc of
+      Right list -> "[" ++ unlines (map decodeResult list) ++ "]"
       Left _ -> ""