Remove RenderType datatype

src/FoldableHelp.hs

@@ -0,0 +1,14 @@
+module FoldableHelp
+    ( safeMinimumOn
+    , module Data.Foldable
+    )
+    where
+import Data.Foldable
+
+safeMinimumOn :: (Foldable t,Ord b) => (a -> b) -> t a -> Maybe a
+safeMinimumOn f = foldl' g Nothing
+  where
+    g (Just x) y 
+        | f x < f y = Just x
+        | otherwise = Just y
+    g Nothing y = Just y