week45 mandatory part finished

4 files changed, 90 insertions, 1 deletions

diff --git a/fp2/week3/mart/StdDynSet.icl b/fp2/week3/mart/StdDynSet.icl
index ffc2590..1202ce2 100644
--- a/fp2/week3/mart/StdDynSet.icl
+++ b/fp2/week3/mart/StdDynSet.icl
@@ -14,7 +14,10 @@ instance toString Set
 where toString (Set a) = abort "toString not implemented"

 	

 instance == Set

-where == a b = abort "== instance voor Set nog niet geimplementeerd.\n"

+where 

+	(==) (Set []) (Set []) = True

+	(==) (Set []) _ = False

+	(==) _ (Set []) = False

 

 toSet :: a -> Set | Set a

 toSet a = Set [dynamic a]

diff --git a/fp2/week45/mart/RefactorX b/fp2/week45/mart/RefactorX
new file mode 100755
index 0000000..a700eaa
--- /dev/null
+++ b/fp2/week45/mart/RefactorX
diff --git a/fp2/week45/mart/RefactorX.dcl b/fp2/week45/mart/RefactorX.dcl
new file mode 100644
index 0000000..e71f36b
--- /dev/null
+++ b/fp2/week45/mart/RefactorX.dcl
@@ -0,0 +1,15 @@
+definition module RefactorX

+

+import StdEnv

+

+:: Expr = NR Int | VAR Name | OP Expr Operator Expr | LET Name Expr Expr

+:: Name :== String

+:: Operator = PLUS | MIN | MUL | DIV

+:: Val = Result Int | Undef

+

+from StdClass import class toString

+

+instance toString Expr

+free :: Expr -> [Name]

+remove_unused_lets :: Expr -> Expr

+eval :: Expr -> Val

diff --git a/fp2/week45/mart/RefactorX.icl b/fp2/week45/mart/RefactorX.icl
new file mode 100644
index 0000000..3898c14
--- /dev/null
+++ b/fp2/week45/mart/RefactorX.icl
@@ -0,0 +1,71 @@
+implementation module RefactorX

+

+import StdEnv

+

+//Start = map toString [E1,E2,E3,E4,E5]

+//Start = map free [E1,E2,E3,E4,E5]

+//Start = map toString (map remove_unused_lets [E1,E2,E3,E4,E5])

+Start = map eval [E1,E2,E3,E4,E5]

+	where

+		E1 = OP (LET "x" (OP (NR 42) MIN (NR 3)) (OP (VAR "x") DIV (NR 0))) PLUS (LET "y" (NR 6) (OP (VAR "y") MUL (VAR "y")))

+		E2 = LET "x" (NR 42) (OP (VAR "x") PLUS (LET "x" (NR 58) (VAR "x")))

+		E3 = LET "x" (NR 1) (LET "y" (NR 2) (LET "x" (NR 3) (NR 4)))

+		E4 = LET "x" (NR 1) (OP (VAR "x") PLUS (VAR "y"))

+		E5 = OP (LET "x" (NR 1) (VAR "x")) MUL (VAR "x")

+

+(<+) infixl 9 :: String a -> String | toString a

+(<+) str a = str +++ toString a

+

+instance toString Operator where

+	toString PLUS = "+"

+	toString MIN = "-"

+	toString MUL = "*"

+	toString DIV = "/"

+ 

+instance toString Expr where

+	toString (NR n) = toString n

+	toString (VAR v) = v

+	toString (LET n e1 e2) = "(let " <+ n <+ "=" <+ e1 <+ " in " <+ e2 <+ ")"

+	toString (OP e1 o e2) = bracket e1 <+ o <+ bracket e2

+		where

+			bracket :: Expr -> String

+			bracket (OP e1 o e2) = "(" <+ (OP e1 o e2) <+ ")"

+			bracket e = toString e

+

+free:: Expr -> [Name]

+free (NR n) = [] 

+free (VAR v) = [v]

+free (OP e1 o e2) = removeDup (free e1 ++ free e2)

+free (LET n e1 e2) = removeMember n (free e2)

+

+remove_unused_lets:: Expr -> Expr

+remove_unused_lets (LET n e1 e2)

+| isMember n (free e2) = (LET n (remove_unused_lets e1) (remove_unused_lets e2))

+| otherwise = remove_unused_lets e2

+remove_unused_lets (OP e1 o e2) = (OP (remove_unused_lets e1) o (remove_unused_lets e2))

+remove_unused_lets e = e

+

+apply:: Operator Val Val -> Val

+apply _ Undef _ = Undef

+apply _ _ Undef = Undef

+apply DIV _ (Result 0) = Undef

+apply o (Result e1) (Result e2) = Result (apply` o e1 e2)

+	where 

+		apply`:: Operator -> Int Int -> Int

+		apply` PLUS = +

+		apply` MIN = -

+		apply` MUL = *

+		apply` DIV = /

+

+

+eval:: Expr -> Val

+eval e = eval` (remove_unused_lets e) []

+	where

+		eval`:: Expr [(Name, Val)] -> Val

+		eval` (NR n) _ = Result n

+		eval` (VAR v) [] = Undef

+		eval` (VAR v) [(n, e):xs]

+		| v == n = e

+		| otherwise = eval` (VAR v) xs

+		eval` (OP e1 o e2) xs = apply o (eval` e1 xs) (eval` e2 xs)

+		eval` (LET n e1 e2) xs = eval` e2 [(n, eval` e1 xs):xs]