1 files changed, 8 insertions, 0 deletions
diff --git a/utility.hs b/utility.hs
index c442f80..a160cb7 100644
--- a/utility.hs
+++ b/utility.hs
@@ -18,3 +18,11 @@ setcompareBy p a@(x:xs) b = length a == length b && setcompareBy p xs (deleteBy
 deleteIndex :: Int -> [a] -> [a]
 deleteIndex 0 (_:xs) = xs
 deleteIndex i (x:xs) | i > 0 = x : deleteIndex (i-1) xs
+
+fromLeft :: Either a b -> a
+fromLeft (Left a) = a
+fromLeft (Right _) = undefined
+
+fromRight :: Either a b -> b
+fromRight (Left _) = undefined
+fromRight (Right b) = b