finished a2

diff --git a/a2/mart/skeleton2.icl b/a2/mart/skeleton2.icl
index 13895ac..4e0ec84 100644 (file)
--- a/a2/mart/skeleton2.icl
+++ b/a2/mart/skeleton2.icl
@@ -122,11 +122,6 @@ fromTuple (x, y) = CONS "Tuple" (PAIR x y)
 instance show_ (a, b) | show_ a & show_ b where\r
        show_ x c = show_ (fromTuple x) c\r
 \r
-Start = [\r
-       show [1, 2, 3],\r
-       show (Bin Tip 5 Tip),\r
-       show ([1, 2], 5) ]\r
-\r
 ///**************** Part 4 *******************************/\r
 :: Result a = Fail | Match a [String]\r
 class parse a :: [String] -> Result a\r
@@ -140,38 +135,48 @@ instance parse Bool where
 instance parse UNIT where\r
        parse ["UNIT" : r]   = Match UNIT r\r
        parse _              = Fail\r
-instance parse (PAIR a b) where\r
-//     parse ["PAIR":r] = Match r\r
+\r
+instance parse (PAIR a b) | parse a & parse b where\r
+       parse ["PAIR":r] = case parse r of\r
+               Match a rs = case parse rs of\r
+                       Match a2 rs2 = Match (PAIR a a2) rs2\r
+                       _ = Fail\r
+               _ = Fail\r
        parse _ = Fail\r
-instance parse (EITHER a b) where\r
-//     parse ["EITHER":r] = Match r\r
+\r
+instance parse (EITHER a b) | parse a & parse b where\r
+       parse ["LEFT":r] = case parse r of\r
+               Match a rs = Match (LEFT a) rs\r
+               _ = Fail\r
+       parse ["RIGHT":r] = case parse r of\r
+               Match a rs = Match (RIGHT a) rs\r
+               _ = Fail\r
+       parse _ = Fail\r
+\r
+instance parse (CONS a) | parse a where\r
+       parse ["CONS",s:r] = case parse r of\r
+               Match a rs = Match (CONS s a) rs\r
+               _ = Fail\r
        parse _ = Fail\r
-instance parse (CONS a) where\r
-//     parse ["CONS",s:r]\r
-       parse_ = Fail\r
-\r
-instance parse (Tree a) | parse a where parse list = Fail // should be improved\r
-\r
-:: T = C\r
-\r
-///**************** Starts *******************************/\r
-//\r
-//Start = ("add your own Start rule!\n", Start4)\r
-//\r
-//// Possible tests:\r
-////Start1 :: ([String],Result T)\r
-////Start1 = (strings,parse strings) where strings = show C\r
-//\r
-////Start2 :: ([String],Result (Int,Bool))\r
-////Start2 = (strings,parse strings) where strings = show (1,False)\r
-//\r
-////Start3 :: ([String],Result [Int])\r
-////Start3 = (strings,parse strings) where strings = show l; l :: [Int]; l = [1..4]\r
-//\r
-//Start4 :: ([String],Result (Tree Int))\r
-//Start4 = (strings,parse strings)\r
-//where\r
-//     strings = show t\r
-//     \r
-//     t :: Tree Int\r
-//     t = Bin (Bin Tip 2 (Bin Tip 3 Tip)) 4 (Bin (Bin Tip 5 Tip) 6 Tip)\r
+\r
+toTree :: (TreeG a) -> Tree a\r
+toTree (LEFT (CONS _ UNIT)) = Tip\r
+toTree (RIGHT (CONS _ (PAIR a (PAIR l r)))) = Bin l a r\r
+\r
+instance parse (Tree a) | parse a where\r
+       parse x = case parse x of\r
+               Match a r = Match (toTree a) r\r
+               _ = Fail\r
+\r
+instance parse [a] | parse a where\r
+       parse x = case parse x of\r
+               Match a r = Match (toList a) r\r
+               _ = Fail\r
+\r
+toTuple :: (TupG a b) -> (a, b)\r
+toTuple (CONS "Tuple" (PAIR a b)) = (a, b)\r
+\r
+instance parse (a, b) | parse a & parse b where\r
+       parse x = case parse x of\r
+               Match a r = Match (toTuple a) r\r
+               _ = Fail\r