vault backup: 2025-01-15 21:52:02

Untitled.md

@@ -1,6 +1,24 @@
 ```haskell
 add :: (Int -> Int) -> Int
 add x y = x+y
+
+instance Eq Bool where
+    True == True = True
+    False == False = True
+    _ == _ = False
+
+instance (Eq a, Eq b) => Eq (a, b) where
+    (x1, y1) == (x2, y2) = x1 == x2 && y1 == y2
+
+-- A value that exists
+myValue :: Maybe Int
+myValue = Just 42
+
+-- A value that doesn't exist
+noValue :: Maybe Int
+noValue = Nothing
+
+
 ```