1 files changed, 44 insertions, 0 deletions
diff --git a/src/Util.hs b/src/Util.hs
new file mode 100644
index 0000000..98943f0
--- /dev/null
+++ b/src/Util.hs
@@ -0,0 +1,44 @@
+module Util where
+
+import Control.Monad
+import System.Exit
+
+
+fixpoint :: Eq a => (a -> a) -> a -> a
+fixpoint f initVal =
+    let values = iterate f initVal
+        pairs = zip values (tail values)
+    in fst . head $ dropWhile (uncurry (/=)) pairs
+
+tryEither :: Either String a -> IO a
+tryEither (Left err) = die err
+tryEither (Right x) = return x
+
+tryEither' :: Show e => Either e a -> IO a
+tryEither' (Left err) = die (show err)
+tryEither' (Right x) = return x
+
+fromRight :: Either a b -> b
+fromRight (Right x) = x
+fromRight (Left _) = error "fromRight on Left"
+
+isRight :: Either a b -> Bool
+isRight (Right _) = True
+isRight (Left _) = False
+
+while :: Monad m => a -> (a -> m (Maybe a)) -> m ()
+while val f = f val >>= \case
+    Nothing   -> return ()
+    Just val' -> while val' f
+
+whenM :: Monad m => m Bool -> m a -> m ()
+whenM b a = b >>= \b' -> if b' then void a else return ()
+
+ifM :: Monad m => m Bool -> m a -> m a -> m a
+ifM b t e = b >>= \b' -> if b' then t else e
+
+splitOn :: Eq a => a -> [a] -> [[a]]
+splitOn _   [] = [[]]
+splitOn spl (x:xs)
+    | x == spl  = [] : splitOn spl xs
+    | otherwise = let (r : rs) = splitOn spl xs in (x:r) : rs