diff --git a/sample-programs/basic-1 b/sample-programs/basic-1.crf
similarity index 100%
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diff --git a/sample-programs/basic-2 b/sample-programs/basic-2.crf
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diff --git a/sample-programs/basic-3 b/sample-programs/basic-3.crf
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diff --git a/sample-programs/basic-4 b/sample-programs/basic-4.crf
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diff --git a/sample-programs/basic-5 b/sample-programs/basic-5.crf
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diff --git a/sample-programs/basic-6 b/sample-programs/basic-6.crf
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diff --git a/sample-programs/basic-7 b/sample-programs/basic-7.crf
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diff --git a/sample-programs/basic-8 b/sample-programs/basic-8.crf
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diff --git a/sample-programs/basic-9 b/sample-programs/basic-9.crf
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diff --git a/test_program.crf b/test_program.crf
index 0c7ce1e..1977b7e 100644
--- a/test_program.crf
+++ b/test_program.crf
@@ -1,28 +1,28 @@
--- data Maybe (a) where {
---     Nothing : Maybe (a)
---     Just : a -> Maybe (a)
---     };
+data Maybe () where {
+    Nothing : Maybe
+    Just : Int -> Maybe
+    };
 
--- fmap : (a -> b) -> Maybe (a) -> Maybe (b) ;
--- fmap f ma = case ma of {
---     Nothing => Nothing ;
---     Just a => Just (f a) ;
--- };
+fmap : (Int -> Int) -> Maybe -> Maybe ;
+fmap f ma = case ma of {
+    Nothing => Nothing ;
+    Just a => Just (f a) ;
+};
 
--- pure : a -> Maybe (a) ;
--- pure x = Just x ;
+pure : Int -> Maybe ;
+pure x = Just x ;
 
--- ap mf ma = case mf of {
---     Just f => case ma of {
---         Nothing => Nothing;
---         Just a => Just (f a);
---     };
---     Nothing => Nothing;
--- };
+ap mf ma = case mf of {
+    Just f => case ma of {
+        Nothing => Nothing;
+        Just a => Just (f a);
+    };
+    Nothing => Nothing;
+};
     
--- return = pure;
+return = pure;
 
--- bind ma f = case ma of {
---     Nothing => Nothing ;
---     Just a => f a ;
--- };
+bind ma f = case ma of {
+    Nothing => Nothing ;
+    Just a => f a ;
+};