Expansion of testing suite to cover incl. library

Expands the testing suite to verify behavior of provided library
functions. Updates the README further for clarification on important
concepts.

src/Library.hs

@@ -30,14 +30,13 @@ library = evalTricu Map.empty $ parseTricu $ unlines
   , "matchBool = (\\ot of : triage of (\\_ : ot) (\\_ _ : ot))"
   , "matchList = (\\oe oc : triage oe _ oc)"
   , "matchPair = (\\op : triage _ _ op)"
+  , "not = matchBool false true"
   , "and = matchBool id (\\z : false)"
   , "if = (\\cond then else : t (t else (t t then)) t cond)"
-  , "test = triage \"leaf\" (\\z : \"stem\") (\\a b : \"fork\")"
+  , "test = triage \"Leaf\" (\\z : \"Stem\") (\\a b : \"Fork\")"
   , "emptyList = matchList true (\\y z : false)"
-  , "nonEmptyList = matchList false (\\y z : true)"
   , "head = matchList t (\\hd tl : hd)"
   , "tail = matchList t (\\hd tl : tl)"
-  , "isLeaf = (\\_ : triage true false false)"
   , "listConcat = y (\\self : matchList (\\k : k) (\\h r k : pair h (self r k)))"
   , "lAnd = triage (\\x : false) (\\_ x : x) (\\_ _ x : x)"
   , "lOr = triage (\\x : x) (\\_ _ : true) (\\_ _ x : true)"

src/Main.hs

@@ -12,7 +12,7 @@ import Text.Megaparsec (runParser)
 
 main :: IO ()
 main = do
-  putStrLn "Welcome to the Tricu Interpreter"
+  putStrLn "Welcome to the tricu Interpreter"
   putStrLn "You can exit at any time by typing and entering: "
   putStrLn ":_exit"
   repl library

src/REPL.hs

@@ -28,7 +28,7 @@ repl env = runInputT defaultSettings (loop env)
           case Map.lookup "__result" newEnv of
             Just r -> do
               outputStrLn $ "tricu > " ++ show r
-              outputStrLn $ "DECODE -: " ++ decodeResult r
+              outputStrLn $ "DECODE -: \"" ++ decodeResult r ++ "\""
             Nothing -> return ()
           loop newEnv
 
@@ -36,7 +36,7 @@ decodeResult :: T -> String
 decodeResult tc = case toNumber tc of
   Right num -> show num
   Left _ -> case toString tc of
-    Right str -> "\"" ++ str ++ "\""
+    Right str -> str
     Left _ -> case toList tc of
       Right list -> "[" ++ intercalate ", " (map decodeResult list) ++ "]"
       Left _ -> ""