Redo tree composition

src/TreeHelp.hs

@@ -19,6 +19,7 @@ module TreeHelp
     , addToTrunk
     , inorderNumberTree
     , updateSingleNodes
+    , updateAllNodes
     , updateRandNode
     , safeUpdateSingleNode
     , msafeUpdateSingleNode
@@ -80,6 +81,14 @@ applyToSubforest is = applyToSubtree is . over branches
 --    | otherwise = Node x (applyToSubTrunkBy cond f t : ts)
 --applyToSubTrunkBy _ _ t = t
 
+updateAllNodes :: (a -> Bool) -> (Tree a -> Tree a) -> Tree a -> Tree a
+updateAllNodes f update t@(Node x ts)
+    | f x       = update t
+    | otherwise = updateChildren
+  where
+    updateChildren = Node x (map (updateAllNodes f update) ts)
+
+
 -- gives the list of all updates to a single node
 -- there must be a better way of doing something like this
 updateSingleNodes :: (a -> Bool) -> (Tree a -> Tree a) -> Tree a -> [Tree a]